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• #OOW 2012 @PARIS...talking Oracle and Clouds, and Optimized Datacenter

  - by Eric Bezille

  For those of you who want to get most out of Oracle technologies to evolve your IT to the Next Wave, I encourage you to register to the up coming Oracle Optimized Datacenter event that will take place in Paris on November 28th. You will get the opportunity to exchange with Oracle experts and customers having successfully evolve their IT by leveraging Oracle technologies. You will also get the latest news on some of the Oracle systems announcements made during OOW 2012. During this event we will make an update about Oracle and Clouds, from private to public and hybrid models. So in preparing this session, I thought it was a good start to make a status of Cloud Computing in France, and CIO requirements in particular. Starting in 2009 with the first Cloud Camp in Paris, the market has evolved, but the basics are still the same : think hybrid. From Traditional IT to Clouds One size doesn't fit all, and for big companies having already an IT in place, there will be parts eligible to external (public) cloud, and parts that would be required to stay inside the firewalls, so ability to integrate both side is key.  None the less, one of the major impact of Cloud Computing trend on IT, reported by Forrester, is the pressure it makes on CIO to evolve towards the same model that end-users are now used to in their day to day life, where self-service and flexibility are paramount. This is what is driving IT to transform itself toward "a Global Service Provider", or for some as "IT "is" the Business" (see : Gartner Identifies Four Futures for IT and CIO), and for both models toward a Private Cloud Service Provider. In this journey, there is still a big difference between most of existing external Cloud and a firm IT : the number of applications that a CIO has to manage. Most cloud providers today are overly specialized, but at the end of the day, there are really few business processes that rely on only one application. So CIOs has to combine everything together external and internal. And for the internal parts that they will have to make them evolve to a Private Cloud, the scope can be very large. This will often require CIOs to evolve from their traditional approach to more disruptive ones, the time has come to introduce new standards and processes, if they want to succeed. So let's have a look at the different Cloud models, what type of users they are addressing, what value they bring and most importantly what needs to be done by the  Cloud Provider, and what is left over to the user. IaaS, PaaS, SaaS : what's provided and what needs to be done First of all the Cloud Provider will have to provide all the infrastructure needed to deliver the service. And the more value IT will want to provide, the more IT will have to deliver and integrate : from disks to applications. As we can see in the above picture, providing pure IaaS, left a lot to cover for the end-user, that’s why the end-user targeted by this Cloud Service is IT people. If you want to bring more value to developers, you need to provide to them a development platform ready to use, which is what PaaS is standing for, by providing not only the processors power, storage and OS, but also the Database and Middleware platform. SaaS being the last mile of the Cloud, providing an application ready to use by business users, the remaining part for the end-users being configuring and specifying the application for their specific usage. In addition to that, there are common challenges encompassing all type of Cloud Services : Security : covering all aspect, not only of users management but also data flows and data privacy Charge back : measuring what is used and by whom Application management : providing capabilities not only to deploy, but also to upgrade, from OS for IaaS, Database, and Middleware for PaaS, to a full Business Application for SaaS. Scalability : ability to evolve ALL the components of the Cloud Provider stack as needed Availability : ability to cover “always on” requirements Efficiency : providing a infrastructure that leverage shared resources in an efficient way and still comply to SLA (performances, availability, scalability, and ability to evolve) Automation : providing the orchestration of ALL the components in all service life-cycle (deployment, growth & shrink (elasticity), upgrades,...) Management : providing monitoring, configuring and self-service up to the end-users Oracle Strategy and Clouds For CIOs to succeed in their Private Cloud implementation, means that they encompass all those aspects for each component life-cycle that they selected to build their Cloud. That’s where a multi-vendors layered approach comes short in terms of efficiency. That’s the reason why Oracle focus on taking care of all those aspects directly at Engineering level, to truly provide efficient Cloud Services solutions for IaaS, PaaS and SaaS. We are going as far as embedding software functions in hardware (storage, processor level,...) to ensure the best SLA with the highest efficiency. The beauty of it, as we rely on standards, is that the Oracle components that you are running today in-house, are exactly the same that we are using to build Clouds, bringing you flexibility, reversibility and fast path to adoption. With Oracle Engineered Systems (Exadata, Exalogic & SPARC SuperCluster, more specifically, when talking about Cloud), we are delivering all those components hardware and software already engineered together at Oracle factory, with a single pane of glace for the management of ALL the components through Oracle Enterprise Manager, and with high-availability, scalability and ability to evolve by design. To give you a feeling of what does that bring in terms just of implementation project timeline, for example with Oracle SPARC SuperCluster, we have a consistent track of record to have the system plug into existing Datacenter and ready in a week. This includes Oracle Database, OS, virtualization, Database Storage (Exadata Storage Cells in this case), Application Storage, and all network configuration. This strategy enable CIOs to very quickly build Cloud Services, taking out not only the complexity of integrating everything together but also taking out the automation and evolution complexity and cost. I invite you to discuss all those aspect in regards of your particular context face2face on November 28th.

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• Node Serialization in NetBeans Platform 7.0

  - by Geertjan

  Node serialization makes sense when you're not interested in the data (since that should be serialized to a database), but in the state of the application. For example, when the application restarts, you want the last selected node to automatically be selected again. That's not the kind of information you'll want to store in a database, hence node serialization is not about data serialization but about application state serialization. I've written about this topic in October 2008, here and here, but want to show how to do this again, using NetBeans Platform 7.0. Somewhere I remember reading that this can't be done anymore and that's typically the best motivation for me, i.e., to prove that it can be done after all. Anyway, in a standard POJO/Node/BeanTreeView scenario, do the following: Remove the "@ConvertAsProperties" annotation at the top of the class, which you'll find there if you used the Window Component wizard. We're not going to use property-file based serialization, but plain old java.io.Serializable  instead. In the TopComponent, assuming it is named "UserExplorerTopComponent", typically at the end of the file, add the following: @Override public Object writeReplace() { //We want to work with one selected item only //and thanks to BeanTreeView.setSelectionMode, //only one node can be selected anyway: Handle handle = NodeOp.toHandles(em.getSelectedNodes())[0]; return new ResolvableHelper(handle); } public final static class ResolvableHelper implements Serializable { private static final long serialVersionUID = 1L; public Handle selectedHandle; private ResolvableHelper(Handle selectedHandle) { this.selectedHandle = selectedHandle; } public Object readResolve() { WindowManager.getDefault().invokeWhenUIReady(new Runnable() { @Override public void run() { try { //Get the TopComponent: UserExplorerTopComponent tc = (UserExplorerTopComponent) WindowManager.getDefault().findTopComponent("UserExplorerTopComponent"); //Get the display text to search for: String selectedDisplayName = selectedHandle.getNode().getDisplayName(); //Get the root, which is the parent of the node we want: Node root = tc.getExplorerManager().getRootContext(); //Find the node, by passing in the root with the display text: Node selectedNode = NodeOp.findPath(root, new String[]{selectedDisplayName}); //Set the explorer manager's selected node: tc.getExplorerManager().setSelectedNodes(new Node[]{selectedNode}); } catch (PropertyVetoException ex) { Exceptions.printStackTrace(ex); } catch (IOException ex) { Exceptions.printStackTrace(ex); } } }); return null; } } Assuming you have a node named "UserNode" for a type named "User" containing a property named "type", add the bits in bold below to your "UserNode": public class UserNode extends AbstractNode implements Serializable { static final long serialVersionUID = 1L; public UserNode(User key) { super(Children.LEAF); setName(key.getType()); } @Override public Handle getHandle() { return new CustomHandle(this, getName()); } public class CustomHandle implements Node.Handle { static final long serialVersionUID = 1L; private AbstractNode node = null; private final String searchString; public CustomHandle(AbstractNode node, String searchString) { this.node = node; this.searchString = searchString; } @Override public Node getNode() { node.setName(searchString); return node; } } } Run the application and select one of the user nodes. Close the application. Start it up again. The user node is not automatically selected, in fact, the window does not open, and you will see this in the output: Caused: java.io.InvalidClassException: org.serialization.sample.UserNode; no valid constructor Read this article and then you'll understand the need for this class: public class BaseNode extends AbstractNode { public BaseNode() { super(Children.LEAF); } public BaseNode(Children kids) { super(kids); } public BaseNode(Children kids, Lookup lkp) { super(kids, lkp); } } Now, instead of extending AbstractNode in your UserNode, extend BaseNode. Then the first non-serializable superclass of the UserNode has an explicitly declared no-args constructor, Do the same as the above for each node in the hierarchy that needs to be serialized. If you have multiple nodes needing serialization, you can share the "CustomHandle" inner class above between all the other nodes, while all the other nodes will also need to extend BaseNode (or provide their own non-serializable super class that explicitly declares a no-args constructor). Now, when I run the application, I select a node, then I close the application, restart it, and the previously selected node is automatically selected when the application has restarted.

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• OpenGL problem with FBO integer texture and color attachment

  - by Grieverheart

  In my simple renderer, I have 2 FBOs one that contains diffuse, normals, instance ID and depth in that order and one that I use store the ssao result. The textures I use for the first FBO are RGB8, RGBA16F, R32I and GL_DEPTH_COMPONENT32F for the depth. For the second FBO I use an R16F texture. My rendering process is to first render to everything I mentioned in the first FBO, then bind depth and normals textures for reading for the ssao pass and write to the second FBO. After that I bind the second FBO's texture for reading in my blur shader and bind the first FBO for writing. What I intend to do is to write the blurred ssao value to the alpha component of the Normals texture. Here are where the problems start. First of all, I use shading language 3.3, which my graphics card does support. I manage ouputs in my shaders using layout(location = #). Now, the normals texture should be bound to color attachment 1, but when I use 1, it seems to write to my diffuse texture which should be in color attachment 0. When I instead use layout(location = 0), it gets correctly written to my normals texture. Besides this, my instance ID texture also gets resets after running the blur shader which is weird because if I use a float texture and write to it instanceID / nInstances, the texture doesn't get reset after the blur shader has ran. Here is how I prepare my first FBO: bool CGBuffer::Init(unsigned int WindowWidth, unsigned int WindowHeight){ //Create FBO glGenFramebuffers(1, &m_fbo); glBindFramebuffer(GL_DRAW_FRAMEBUFFER, m_fbo); //Create gbuffer and Depth Buffer Textures glGenTextures(GBUFF_NUM_TEXTURES, &m_textures[0]); glGenTextures(1, &m_depthTexture); //prepare gbuffer for(unsigned int i = 0; i < GBUFF_NUM_TEXTURES; i++){ glBindTexture(GL_TEXTURE_2D, m_textures[i]); if(i == GBUFF_TEXTURE_TYPE_NORMAL) glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA16F, WindowWidth, WindowHeight, 0, GL_RGBA, GL_FLOAT, NULL); else if(i == GBUFF_TEXTURE_TYPE_DIFFUSE) glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB8, WindowWidth, WindowHeight, 0, GL_RGB, GL_FLOAT, NULL); else if(i == GBUFF_TEXTURE_TYPE_ID) glTexImage2D(GL_TEXTURE_2D, 0, GL_R32I, WindowWidth, WindowHeight, 0, GL_RED_INTEGER, GL_INT, NULL); else{ std::cout << "Error in FBO initialization" << std::endl; return false; } glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT0 + i, GL_TEXTURE_2D, m_textures[i], 0); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP); } //prepare depth buffer glBindTexture(GL_TEXTURE_2D, m_depthTexture); glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT32F, WindowWidth, WindowHeight, 0, GL_DEPTH_COMPONENT, GL_FLOAT, NULL); glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, m_depthTexture, 0); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE, GL_NONE); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP); GLenum DrawBuffers[] = {GL_COLOR_ATTACHMENT0, GL_COLOR_ATTACHMENT1, GL_COLOR_ATTACHMENT2}; glDrawBuffers(GBUFF_NUM_TEXTURES, DrawBuffers); GLenum Status = glCheckFramebufferStatus(GL_FRAMEBUFFER); if(Status != GL_FRAMEBUFFER_COMPLETE){ std::cout << "FB error, status 0x" << std::hex << Status << std::endl; return false; } //Restore default framebuffer glBindFramebuffer(GL_FRAMEBUFFER, 0); return true; } where I use an enum defined as, enum GBUFF_TEXTURE_TYPE{ GBUFF_TEXTURE_TYPE_DIFFUSE, GBUFF_TEXTURE_TYPE_NORMAL, GBUFF_TEXTURE_TYPE_ID, GBUFF_NUM_TEXTURES }; Am I missing some kind of restriction? Does the color attachment of the FBO's textures somehow gets reset i.e. I'm using a re-size function which re-sizes the textures of the FBO but should I perhaps call glFramebufferTexture2D again too? EDIT: Here is the shader in question: #version 330 core uniform sampler2D aoSampler; uniform vec2 TEXEL_SIZE; // x = 1/res x, y = 1/res y uniform bool use_blur; noperspective in vec2 TexCoord; layout(location = 0) out vec4 out_AO; void main(void){ if(use_blur){ float result = 0.0; for(int i = -1; i < 2; i++){ for(int j = -1; j < 2; j++){ vec2 offset = vec2(TEXEL_SIZE.x * i, TEXEL_SIZE.y * j); result += texture(aoSampler, TexCoord + offset).r; // -0.004 because the texture seems to be a bit displaced } } out_AO = vec4(vec3(0.0), result / 9); } else out_AO = vec4(vec3(0.0), texture(aoSampler, TexCoord).r); }

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• Black Screen: How to set Projection/View Matrix

  - by Lisa

  I have a Windows Phone 8 C#/XAML with DirectX component project. I'm rendering some particles, but each particle is a rectangle versus a square (as I've set the vertices to be positions equally offset from each other). I used an Identity matrix in the view and projection matrix. I decided to add the windows aspect ratio to prevent the rectangles. But now I get a black screen. None of the particles are rendered now. I don't know what's wrong with my matrices. Can anyone see the problem? These are the default matrices in Microsoft's project example. View Matrix: XMVECTOR eye = XMVectorSet(0.0f, 0.7f, 1.5f, 0.0f); XMVECTOR at = XMVectorSet(0.0f, -0.1f, 0.0f, 0.0f); XMVECTOR up = XMVectorSet(0.0f, 1.0f, 0.0f, 0.0f); XMStoreFloat4x4(&m_constantBufferData.view, XMMatrixTranspose(XMMatrixLookAtRH(eye, at, up))); Projection Matrix: void CubeRenderer::CreateWindowSizeDependentResources() { Direct3DBase::CreateWindowSizeDependentResources(); float aspectRatio = m_windowBounds.Width / m_windowBounds.Height; float fovAngleY = 70.0f * XM_PI / 180.0f; if (aspectRatio < 1.0f) { fovAngleY /= aspectRatio; } XMStoreFloat4x4(&m_constantBufferData.projection, XMMatrixTranspose(XMMatrixPerspectiveFovRH(fovAngleY, aspectRatio, 0.01f, 100.0f))); } I've tried modifying them to use cocos2dx's WP8 example. XMMATRIX identityMatrix = XMMatrixIdentity(); float fovy = 60.0f; float aspect = m_windowBounds.Width / m_windowBounds.Height; float zNear = 0.1f; float zFar = 100.0f; float xmin, xmax, ymin, ymax; ymax = zNear * tanf(fovy * XM_PI / 360); ymin = -ymax; xmin = ymin * aspect; xmax = ymax * aspect; XMMATRIX tmpMatrix = XMMatrixPerspectiveOffCenterRH(xmin, xmax, ymin, ymax, zNear, zFar); XMMATRIX projectionMatrix = XMMatrixMultiply(tmpMatrix, identityMatrix); // View Matrix float fEyeX = m_windowBounds.Width * 0.5f; float fEyeY = m_windowBounds.Height * 0.5f; float fEyeZ = m_windowBounds.Height / 1.1566f; float fLookAtX = m_windowBounds.Width * 0.5f; float fLookAtY = m_windowBounds.Height * 0.5f; float fLookAtZ = 0.0f; float fUpX = 0.0f; float fUpY = 1.0f; float fUpZ = 0.0f; XMMATRIX tmpMatrix2 = XMMatrixLookAtRH(XMVectorSet(fEyeX,fEyeY,fEyeZ,0.f), XMVectorSet(fLookAtX,fLookAtY,fLookAtZ,0.f), XMVectorSet(fUpX,fUpY,fUpZ,0.f)); XMMATRIX viewMatrix = XMMatrixMultiply(tmpMatrix2, identityMatrix); XMStoreFloat4x4(&m_constantBufferData.view, viewMatrix); Vertex Shader cbuffer ModelViewProjectionConstantBuffer : register(b0) { //matrix model; matrix view; matrix projection; }; struct VertexInputType { float4 position : POSITION; float2 tex : TEXCOORD0; float4 color : COLOR; }; struct PixelInputType { float4 position : SV_POSITION; float2 tex : TEXCOORD0; float4 color : COLOR; }; PixelInputType main(VertexInputType input) { PixelInputType output; // Change the position vector to be 4 units for proper matrix calculations. input.position.w = 1.0f; //===================================== // TODO: ADDED for testing input.position.z = 0.0f; //===================================== // Calculate the position of the vertex against the world, view, and projection matrices. //output.position = mul(input.position, model); output.position = mul(input.position, view); output.position = mul(output.position, projection); // Store the texture coordinates for the pixel shader. output.tex = input.tex; // Store the particle color for the pixel shader. output.color = input.color; return output; } Before I render the shader, I set the view/projection matrices into the constant buffer void ParticleRenderer::SetShaderParameters() { ViewProjectionConstantBuffer* dataPtr; D3D11_MAPPED_SUBRESOURCE mappedResource; DX::ThrowIfFailed(m_d3dContext->Map(m_constantBuffer.Get(), 0, D3D11_MAP_WRITE_DISCARD, 0, &mappedResource)); dataPtr = (ViewProjectionConstantBuffer*)mappedResource.pData; dataPtr->view = m_constantBufferData.view; dataPtr->projection = m_constantBufferData.projection; m_d3dContext->Unmap(m_constantBuffer.Get(), 0); // Now set the constant buffer in the vertex shader with the updated values. m_d3dContext->VSSetConstantBuffers(0, 1, m_constantBuffer.GetAddressOf() ); // Set shader texture resource in the pixel shader. m_d3dContext->PSSetShaderResources(0, 1, &m_textureView); } Nothing, black screen... I tried so many different look at, eye, and up vectors. I tried transposing the matrices. I've set the particle center position to always be (0, 0, 0), I tried different positions too, just to make sure they're not being rendered offscreen.

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• NDepend Evaluation: Part 3

  - by Anthony Trudeau

  NDepend is a Visual Studio add-in designed for intense code analysis with the goal of high code quality. NDepend uses a number of metrics and aggregates the data in pleasing static and active visual reports. My evaluation of NDepend will be broken up into several different parts. In the first part of the evaluation I looked at installing the add-in.  And in the last part I went over my first impressions including an overview of the features.  In this installment I provide a little more detail on a few of the features that I really like. Dependency Matrix The dependency matrix is one of the rich visual components provided with NDepend.  At a glance it lets you know where you have coupling problems including cycles.  It does this with number indicating the weight of the dependency and a color-coding that indicates the nature of the dependency. Green and blue cells are direct dependencies (with the difference being whether the relationship is from row-to-column or column-to-row).  Black cells are the ones that you really want to know about.  These indicate that you have a cycle.  That is, type A refers to type B and type B also refers to Type A. But, that’s not the end of the story.  A handy pop-up appears when you hover over the cell in question.  It explains the color, the dependency, and provides several interesting links that will teach you more than you want to know about the dependency. You can double-click the problem cells to explode the dependency.  That will show the dependencies on a method-by-method basis allowing you to more easily target and fix the problem.  When you’re done you can click the back button on the toolbar. Dependency Graph The dependency graph is another component provided.  It’s complementary to the dependency matrix, but it isn’t as easy to identify dependency issues using the window. On a positive note, it does provide more information than the matrix. My biggest issue with the dependency graph is determining what is shown.  This was not readily obvious.  I ended up using the navigation buttons to get an acceptable view.  I would have liked to choose what I see. Once you see the types you want you can get a decent idea of coupling strength based on the width of the dependency lines.  Double-arrowed lines are problematic and are shown in red.  The size of the boxes will be related to the metric being displayed.  This is controlled using the Box Size drop-down in the toolbar.  Personally, I don’t find the size of the box to be helpful, so I change it to Constant Font. One nice thing about the display is that you can see the entire path of dependencies when you hover over a type.  This is done by color-coding the dependencies and dependants.  It would be nice if selecting the box for the type would lock the highlighting in place. I did find a perhaps unintended work-around to the color-coding.  You can lock the color-coding in by hovering over the type, right-clicking, and then clicking on the canvas area to clear the pop-up menu.  You can then do whatever with it including saving it to an image file with the color-coding. CQL NDepend uses a code query language (CQL) to work with your code just like it was a database.  CQL cannot be confused with the robustness of T-SQL or even LINQ, but it represents an impressive attempt at providing an expressive way to enumerate and interrogate your code. There are two main windows you’ll use when working with CQL.  The CQL Query Explorer allows you to define what queries (rules) are run as part of a report – I immediately unselected rules that I don’t want in my results.  The CQL Query Edit window is where you can view or author your own rules.  The explorer window is pretty self-explanatory, so I won’t mention it further other than to say that any queries you author will appear in the custom group. Authoring your own queries is really hard to screw-up.  The Intellisense-like pop-ups tell you what you can do while making composition easy.  I was able to create a query within two minutes of playing with the editor.  My query warns if any types that are interfaces don’t start with an “I”. WARN IF Count > 0 IN SELECT TYPES WHERE IsInterface AND !NameLike “I” The results from the CQL Query Edit window are immediate. That fact makes it useful for ad hoc querying.  It’s worth mentioning two things that could make the experience smoother.  First, out of habit from using Visual Studio I expect to be able to scroll and press Tab to select an item in the list (like Intellisense).  You have to press Enter when you scroll to the item you want.  Second, the commands are case-sensitive.  I don’t see a really good reason to enforce that. CQL has a lot of potential not just in enforcing code quality, but also enforcing architectural constraints that your enterprise has defined. Up Next My next update will be the final part of the evaluation.  I will summarize my experience and provide my conclusions on the NDepend add-in. ** View Part 1 of the Evaluation ** ** View Part 2 of the Evaluation ** Disclaimer: Patrick Smacchia contacted me about reviewing NDepend. I received a free license in return for sharing my experiences and talking about the capabilities of the add-in on this site. There is no expectation of a positive review elicited from the author of NDepend.

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• Inside BackgroundWorker

  - by João Angelo

  The BackgroundWorker is a reusable component that can be used in different contexts, but sometimes with unexpected results. If you are like me, you have mostly used background workers while doing Windows Forms development due to the flexibility they offer for running a background task. They support cancellation and give events that signal progress updates and task completion. When used in Windows Forms, these events (ProgressChanged and RunWorkerCompleted) get executed back on the UI thread where you can freely access your form controls. However, the logic of the progress changed and worker completed events being invoked in the thread that started the background worker is not something you get directly from the BackgroundWorker, but instead from the fact that you are running in the context of Windows Forms. Take the following example that illustrates the use of a worker in three different scenarios: – Console Application or Windows Service; – Windows Forms; – WPF. using System; using System.ComponentModel; using System.Threading; using System.Windows.Forms; using System.Windows.Threading; class Program { static AutoResetEvent Synch = new AutoResetEvent(false); static void Main() { var bw1 = new BackgroundWorker(); var bw2 = new BackgroundWorker(); var bw3 = new BackgroundWorker(); Console.WriteLine("DEFAULT"); var unspecializedThread = new Thread(() => { OutputCaller(1); SynchronizationContext.SetSynchronizationContext( new SynchronizationContext()); bw1.DoWork += (sender, e) => OutputWork(1); bw1.RunWorkerCompleted += (sender, e) => OutputCompleted(1); // Uses default SynchronizationContext bw1.RunWorkerAsync(); }); unspecializedThread.IsBackground = true; unspecializedThread.Start(); Synch.WaitOne(); Console.WriteLine(); Console.WriteLine("WINDOWS FORMS"); var windowsFormsThread = new Thread(() => { OutputCaller(2); SynchronizationContext.SetSynchronizationContext( new WindowsFormsSynchronizationContext()); bw2.DoWork += (sender, e) => OutputWork(2); bw2.RunWorkerCompleted += (sender, e) => OutputCompleted(2); // Uses WindowsFormsSynchronizationContext bw2.RunWorkerAsync(); Application.Run(); }); windowsFormsThread.IsBackground = true; windowsFormsThread.SetApartmentState(ApartmentState.STA); windowsFormsThread.Start(); Synch.WaitOne(); Console.WriteLine(); Console.WriteLine("WPF"); var wpfThread = new Thread(() => { OutputCaller(3); SynchronizationContext.SetSynchronizationContext( new DispatcherSynchronizationContext()); bw3.DoWork += (sender, e) => OutputWork(3); bw3.RunWorkerCompleted += (sender, e) => OutputCompleted(3); // Uses DispatcherSynchronizationContext bw3.RunWorkerAsync(); Dispatcher.Run(); }); wpfThread.IsBackground = true; wpfThread.SetApartmentState(ApartmentState.STA); wpfThread.Start(); Synch.WaitOne(); } static void OutputCaller(int workerId) { Console.WriteLine( "bw{0}.{1} | Thread: {2} | IsThreadPool: {3}", workerId, "RunWorkerAsync".PadRight(18), Thread.CurrentThread.ManagedThreadId, Thread.CurrentThread.IsThreadPoolThread); } static void OutputWork(int workerId) { Console.WriteLine( "bw{0}.{1} | Thread: {2} | IsThreadPool: {3}", workerId, "DoWork".PadRight(18), Thread.CurrentThread.ManagedThreadId, Thread.CurrentThread.IsThreadPoolThread); } static void OutputCompleted(int workerId) { Console.WriteLine( "bw{0}.{1} | Thread: {2} | IsThreadPool: {3}", workerId, "RunWorkerCompleted".PadRight(18), Thread.CurrentThread.ManagedThreadId, Thread.CurrentThread.IsThreadPoolThread); Synch.Set(); } } Output: //DEFAULT //bw1.RunWorkerAsync | Thread: 3 | IsThreadPool: False //bw1.DoWork | Thread: 4 | IsThreadPool: True //bw1.RunWorkerCompleted | Thread: 5 | IsThreadPool: True //WINDOWS FORMS //bw2.RunWorkerAsync | Thread: 6 | IsThreadPool: False //bw2.DoWork | Thread: 5 | IsThreadPool: True //bw2.RunWorkerCompleted | Thread: 6 | IsThreadPool: False //WPF //bw3.RunWorkerAsync | Thread: 7 | IsThreadPool: False //bw3.DoWork | Thread: 5 | IsThreadPool: True //bw3.RunWorkerCompleted | Thread: 7 | IsThreadPool: False As you can see the output between the first and remaining scenarios is somewhat different. While in Windows Forms and WPF the worker completed event runs on the thread that called RunWorkerAsync, in the first scenario the same event runs on any thread available in the thread pool. Another scenario where you can get the first behavior, even when on Windows Forms or WPF, is if you chain the creation of background workers, that is, you create a second worker in the DoWork event handler of an already running worker. Since the DoWork executes in a thread from the pool the second worker will use the default synchronization context and the completed event will not run in the UI thread.

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• Confused Why I am getting C1010 error?

  - by bluepixel

  I have three files: Main, slist.h and slist.cpp can be seen at http://forums.devarticles.com/c-c-help-52/confused-why-i-am-getting-c2143-and-c1010-error-259574.html I'm trying to make a program where main reads the list of student names from a file (roster.txt) and inserts all the names in a list in ascending order. This is the full class roster list (notCheckedIN). From here I will read all students who have come to write the exams, each checkin will transfer their name to another list (in ascending order) called present. The final product is notCheckedIN will contain a list of all those students that did not write the exam and present will contain the list of all students who wrote the exam Main File: // Exam.cpp : Defines the entry point for the console application. #include "stdafx.h" #include "iostream" #include "iomanip" #include "fstream" #include "string" #include "slist.h" using namespace std; void OpenFile(ifstream&); void GetClassRoster(SortList&, ifstream&); void InputStuName(SortList&, SortList&); void UpdateList(SortList&, SortList&, string); void Print(SortList&, SortList&); const string END_DATA = "EndData"; int main() { ifstream roster; SortList notCheckedIn; //students present SortList present; //student absent OpenFile(roster); if(!roster) //Make sure file is opened return 1; GetClassRoster(notCheckedIn, roster); //insert the roster list into the notCheckedIn list InputStuName(present, notCheckedIn); Print(present, notCheckedIn); return 0; } void OpenFile(ifstream& roster) //Precondition: roster is pointing to file containing student anmes //Postcondition:IF file does not exist -> exit { string fileName = "roster.txt"; roster.open(fileName.c_str()); if(!roster) cout << "***ERROR CANNOT OPEN FILE :"<< fileName << "***" << endl; } void GetClassRoster(SortList& notCheckedIN, ifstream& roster) //Precondition:roster points to file containing list of student last name // && notCheckedIN is empty //Postcondition:notCheckedIN is filled with the names taken from roster.txt in ascending order { string name; roster >> name; while(roster) { notCheckedIN.Insert(name); roster >> name; } } void InputStuName(SortList& present, SortList& notCheckedIN) //Precondition: present list is empty initially and notCheckedIN list is full //Postcondition: repeated prompting to enter stuName // && notCheckedIN will delete all names found in present // && present will contain names present // && names not found in notCheckedIN will report Error { string stuName; cout << "Enter last name (Enter EndData if none to Enter): "; cin >> stuName; while(stuName!=END_DATA) { UpdateList(present, notCheckedIN, stuName); } } void UpdateList(SortList& present, SortList& notCheckedIN, string stuName) //Precondition:stuName is assigned //Postcondition:IF stuName is present, stuName is inserted in present list // && stuName is removed from the notCheckedIN list // ELSE stuName does not exist { if(notCheckedIN.isPresent(stuName)) { present.Insert(stuName); notCheckedIN.Delete(stuName); } else cout << "NAME IS NOT PRESENT" << endl; } void Print(SortList& present, SortList& notCheckedIN) //Precondition: present and notCheckedIN contains a list of student Names present/not present //Postcondition: content of present and notCheckedIN is printed { cout << "Candidates Present" << endl; present.Print(); cout << "Candidates Absent" << endl; notCheckedIN.Print(); } Header File: //Specification File: slist.h //This file gives the specifications of a list abstract data type //List items inserted will be in order //Class SortList, structured type used to represent an ADT using namespace std; const int MAX_LENGTH = 200; typedef string ItemType; //Class Object (class instance) SortList. Variable of class type. class SortList { //Class Member - components of a class, can be either data or functions public: //Constructor //Post-condition: Empty list is created SortList(); //Const member function. Compiler error occurs if any statement within tries to modify a private data bool isEmpty() const; //Post-condition: == true if list is empty // == false if list is not empty bool isFull() const; //Post-condition: == true if list is full // == false if list is full int Length() const; //Post-condition: size of list void Insert(ItemType item); //Precondition: NOT isFull() && item is assigned //Postcondition: item is in list && Length() = Length()@entry + 1 void Delete(ItemType item); //Precondition: NOT isEmpty() && item is assigned //Postcondition: // IF items is in list at entry // first occurance of item in list is removed // && Length() = Length()@entry -1; // ELSE // list is not changed bool isPresent(ItemType item) const; //Precondition: item is assigned //Postcondition: == true if item is present in list // == false if item is not present in list void Print() const; //Postcondition: All component of list have been output private: int length; ItemType data[MAX_LENGTH]; void BinSearch(ItemType, bool&, int&) const; }; Source File: //Implementation File: slist.cpp //This file gives the specifications of a list abstract data type //List items inserted will be in order //Class SortList, structured type used to represent an ADT #include "iostream" #include "slist.h" using namespace std; // int length; // ItemType data[MAX_SIZE]; //Class Object (class instance) SortList. Variable of class type. SortList::SortList() //Constructor //Post-condition: Empty list is created { length=0; } //Const member function. Compiler error occurs if any statement within tries to modify a private data bool SortList::isEmpty() const //Post-condition: == true if list is empty // == false if list is not empty { return(length==0); } bool SortList::isFull() const //Post-condition: == true if list is full // == false if list is full { return (length==(MAX_LENGTH-1)); } int SortList::Length() const //Post-condition: size of list { return length; } void SortList::Insert(ItemType item) //Precondition: NOT isFull() && item is assigned //Postcondition: item is in list && Length() = Length()@entry + 1 // && list componenet are in ascending order of value { int index; index = length -1; while(index >=0 && item<data[index]) { data[index+1]=data[index]; index--; } data[index+1]=item; length++; } void SortList:elete(ItemType item) //Precondition: NOT isEmpty() && item is assigned //Postcondition: // IF items is in list at entry // first occurance of item in list is removed // && Length() = Length()@entry -1; // && list components are in ascending order // ELSE data array is unchanged { bool found; int position; BinSearch(item,found,position); if (found) { for(int index = position; index < length; index++) data[index]=data[index+1]; length--; } } bool SortList::isPresent(ItemType item) const //Precondition: item is assigned && length <= MAX_LENGTH && items are in ascending order //Postcondition: true if item is found in the list // false if item is not found in the list { bool found; int position; BinSearch(item,found,position); return (found); } void SortList::Print() const //Postcondition: All component of list have been output { for(int x= 0; x<length; x++) cout << data[x] << endl; } void SortList::BinSearch(ItemType item, bool found, int position) const //Precondition: item contains item to be found // && item in the list is an ascending order //Postcondition: IF item is in list, position is returned // ELSE item does not exist in the list { int first = 0; int last = length -1; int middle; found = false; while(!found) { middle = (first+last)/2; if(data[middle]<item) first = middle+1; else if (data[middle] > item) last = middle -1; else found = true; } if(found) position = middle; } I cannot get rid of the C1010 error: fatal error C1010: unexpected end of file while looking for precompiled header. Did you forget to add '#include "stdafx.h"' to your source? Is there a way to get rid of this error? When I included "stdafx.h" I received the following 32 errors (which does not make sense to me why because I referred back to my manual on how to use Class method - everything looks a.ok.) Error 1 error C2871: 'std' : a namespace with this name does not exist c:\..\slist.h 6 Error 2 error C2146: syntax error : missing ';' before identifier 'ItemType' c:\..\slist.h 8 Error 3 error C4430: missing type specifier - int assumed. Note: C++ does not support default-int c:\..\slist.h 8 Error 4 error C4430: missing type specifier - int assumed. Note: C++ does not support default-int c:\..\slist.h 8 Error 5 error C2061: syntax error : identifier 'ItemType' c:\..\slist.h 30 Error 6 error C2061: syntax error : identifier 'ItemType' c:\..\slist.h 34 Error 7 error C2061: syntax error : identifier 'ItemType' c:\..\slist.h 43 Error 8 error C2146: syntax error : missing ';' before identifier 'data' c:\..\slist.h 52 Error 9 error C4430: missing type specifier - int assumed. Note: C++ does not support default-int c:\..\slist.h 52 Error 10 error C4430: missing type specifier - int assumed. Note: C++ does not support default-int c:\..\slist.h 52 Error 11 error C2061: syntax error : identifier 'ItemType' c:\..\slist.h 53 Error 12 error C2146: syntax error : missing ')' before identifier 'item' c:\..\slist.cpp 41 Error 13 error C2761: 'void SortList::Insert(void)' : member function redeclaration not allowed c:\..\slist.cpp 41 Error 14 error C2059: syntax error : ')' c:\..\slist.cpp 41 Error 15 error C2143: syntax error : missing ';' before '{' c:\..\slist.cpp 45 Error 16 error C2447: '{' : missing function header (old-style formal list?) c:\..\slist.cpp 45 Error 17 error C2146: syntax error : missing ')' before identifier 'item' c:\..\slist.cpp 57 Error 18 error C2761: 'void SortList:elete(void)' : member function redeclaration not allowed c:\..\slist.cpp 57 Error 19 error C2059: syntax error : ')' c:\..\slist.cpp 57 Error 20 error C2143: syntax error : missing ';' before '{' c:\..\slist.cpp 65 Error 21 error C2447: '{' : missing function header (old-style formal list?) c:\..\slist.cpp 65 Error 22 error C2146: syntax error : missing ')' before identifier 'item' c:\..\slist.cpp 79 Error 23 error C2761: 'bool SortList::isPresent(void) const' : member function redeclaration not allowed c:\..\slist.cpp 79 Error 24 error C2059: syntax error : ')' c:\..\slist.cpp 79 Error 25 error C2143: syntax error : missing ';' before '{' c:\..\slist.cpp 83 Error 26 error C2447: '{' : missing function header (old-style formal list?) c:\..\slist.cpp 83 Error 27 error C2065: 'data' : undeclared identifier c:\..\slist.cpp 95 Error 28 error C2146: syntax error : missing ')' before identifier 'item' c:\..\slist.cpp 98 Error 29 error C2761: 'void SortList::BinSearch(void) const' : member function redeclaration not allowed c:\..\slist.cpp 98 Error 30 error C2059: syntax error : ')' c:\..\slist.cpp 98 Error 31 error C2143: syntax error : missing ';' before '{' c:\..\slist.cpp 103 Error 32 error C2447: '{' : missing function header (old-style formal list?) c:\..\slist.cpp 103

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• How do I ensure that a JPanel Shrinks when the parent frame is resized?

  - by dah

  I have a basic notes panel that I'm looking to shrink the width of when the parent jframe is resized but it isn't happening. I'm using nested gridbaglayouts. package com.protocase.notes.views; import com.protocase.notes.controller.NotesController; import com.protocase.notes.model.Subject; import com.protocase.notes.model.Note; import com.protocase.notes.model.database.PMSNotesAdapter; import java.awt.Color; import java.awt.GridBagConstraints; import java.awt.GridBagLayout; import javax.swing.BorderFactory; import javax.swing.JButton; import javax.swing.JLabel; import javax.swing.JPanel; import javax.swing.JScrollPane; /** * @author DavidH */ public class NotesViewer extends JPanel { // <editor-fold defaultstate="collapsed" desc="Attributes"> private Subject subject; private NotesController controller; //</editor-fold> // <editor-fold defaultstate="collapsed" desc="Getters N' Setters"> /** * Gets back the current subject. * @return */ public Subject getSubject() { return subject; } public NotesController getController() { return controller; } public void setController(NotesController controller) { this.controller = controller; } /** * Should clear the panel of the current subject and load the details for * the other object. * @param subject */ public void setSubject(Subject subject) { this.subject = subject; } //</editor-fold> // <editor-fold defaultstate="collapsed" desc="Constructor"> /** * -- Sets up a note viewer with a subject and a controller. Likely this * would be the constructor used if you were passing off from another * NoteViewer or something else that used a notes adapter or controller. * @param subject * @param controller */ public NotesViewer(Subject subject, NotesController controller) { this.subject = subject; this.controller = controller; initComponents(); } /** * -- Sets up a note view with a subject and creates a new controller. This * would be the constructor typically chosen if choosing notes was * infrequent and only one or two notes needs to be displayed. * @param subject */ public NotesViewer(Subject subject) { this(subject, new NotesController(new PMSNotesAdapter())); } /** * -- Sets up a note view without a subject and creates a new controller. * This would be for a note viewer without any notes, perhaps populating * as you choose values in another form. * @param subject */ public NotesViewer() { this(null); } //</editor-fold> // <editor-fold defaultstate="collapsed" desc="initComponents()"> /** * Sets up the view for the NotesViewer */ private void initComponents() { // -- Make a new panel for the header JPanel panel = new JPanel(); panel.setLayout(new GridBagLayout()); GridBagConstraints c = new GridBagConstraints(); c.gridx = 0; c.fill = GridBagConstraints.HORIZONTAL; c.gridy = 0; c.weightx = .5; //c.anchor = GridBagConstraints.NORTHWEST; JLabel label = new JLabel("Viewing Notes for [Subject]"); label.setAlignmentX(JLabel.LEFT_ALIGNMENT); label.setBorder(BorderFactory.createLineBorder(Color.YELLOW)); panel.add(label); JButton newNoteButton = new JButton("New"); c = new GridBagConstraints(); // c.fill = GridBagConstraints.HORIZONTAL; c.gridx = 1; c.gridy = 0; c.weightx = .5; c.anchor = GridBagConstraints.EAST; panel.add(newNoteButton, c); // -- NotePanels c = new GridBagConstraints(); c.fill = GridBagConstraints.HORIZONTAL; c.weightx = 1; c.weighty = 1; c.gridx = 0; c.gridwidth = 2; int y = 1; for (Note n : subject.getNotes()) { c.gridy = y++; panel.add(new NotesPanel(n, controller), c); } this.setLayout(new GridBagLayout()); GridBagConstraints pc = new GridBagConstraints(); pc.gridx = 0; pc.gridy = 0; pc.weightx = 1; pc.weighty = 1; pc.fill = GridBagConstraints.BOTH; panel.setBackground(Color.blue); JScrollPane scroll = new JScrollPane(); scroll.setViewportView(panel); //scroll.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_NEVER); this.add(scroll, pc); //this.add(panel, pc); // -- Add it all to the layout } //</editor-fold> // <editor-fold defaultstate="collapsed" desc="private methods"> //</editor-fold> } package com.protocase.notes.views; import com.protocase.notes.controller.NotesController; import com.protocase.notes.model.Note; import java.awt.CardLayout; import java.awt.Color; import java.awt.Component; import java.awt.Dimension; import java.awt.GridBagConstraints; import java.awt.GridBagLayout; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.text.DateFormat; import java.text.SimpleDateFormat; import javax.swing.BorderFactory; import javax.swing.JButton; import javax.swing.JLabel; import javax.swing.JPanel; import javax.swing.JScrollPane; import javax.swing.JTextArea; import javax.swing.JTextField; import javax.swing.border.BevelBorder; import javax.swing.border.Border; import javax.swing.border.MatteBorder; /** * @author dah01 */ public class NotesPanel extends JPanel { // <editor-fold defaultstate="collapsed" desc="Attributes"> private Note note; private NotesController controller; private CardLayout cardLayout; private JTextArea viewTextArea; private JTextArea editTextArea; //</editor-fold> // <editor-fold defaultstate="collapsed" desc="Getters N' Setters"> public NotesController getController() { return controller; } public void setController(NotesController controller) { this.controller = controller; } public Note getNote() { return note; } public void setNote(Note note) { this.note = note; } //</editor-fold> // <editor-fold defaultstate="collapsed" desc="Constructor"> /** * Sets up a note panel that shows everything about the note. * @param note */ public NotesPanel(Note note, NotesController controller) { this.note = note; cardLayout = new CardLayout(); this.setLayout(cardLayout); // -- Setup the layout manager. this.setBackground(new Color(199, 187, 192)); this.setBorder(new BevelBorder(BevelBorder.RAISED)); // -- ViewPanel this.add("ViewPanel", initViewPanel()); this.add("EditPanel", initEditPanel()); } //</editor-fold> // <editor-fold defaultstate="collapsed" desc="EditPanel"> private JPanel initEditPanel() { JPanel editPanel = new JPanel(); editPanel.setLayout(new GridBagLayout()); GridBagConstraints c = new GridBagConstraints(); c.fill = GridBagConstraints.HORIZONTAL; c.gridy = 0; c.weightx = 1; c.weighty = 0.3; editPanel.add(initCreatorLabel(), c); c.gridy++; editPanel.add(initEditTextScroll(), c); c.gridy++; c.anchor = GridBagConstraints.WEST; c.fill = GridBagConstraints.NONE; editPanel.add(initEditorLabel(), c); c.gridx++; c.anchor = GridBagConstraints.EAST; editPanel.add(initSaveButton(), c); return editPanel; } private JScrollPane initEditTextScroll() { this.editTextArea = new JTextArea(note.getContents()); editTextArea.setLineWrap(true); editTextArea.setWrapStyleWord(true); JScrollPane scrollPane = new JScrollPane(editTextArea); scrollPane.setAlignmentX(JScrollPane.LEFT_ALIGNMENT); Border b = scrollPane.getViewportBorder(); MatteBorder mb = BorderFactory.createMatteBorder(2, 2, 2, 2, Color.BLUE); scrollPane.setBorder(mb); return scrollPane; } private JButton initSaveButton() { final CardLayout l = this.cardLayout; final JPanel p = this; final NotesController c = this.controller; final Note n = this.note; final JTextArea noteText = this.viewTextArea; final JTextArea textToSubmit = this.editTextArea; ActionListener al = new ActionListener() { @Override public void actionPerformed(ActionEvent e) { //controller.saveNote(n); noteText.setText(textToSubmit.getText()); l.next(p); } }; JButton saveButton = new JButton("Save"); saveButton.addActionListener(al); saveButton.setPreferredSize(new Dimension(62, 26)); return saveButton; } //</editor-fold> // <editor-fold defaultstate="collapsed" desc="ViewPanel"> private JPanel initViewPanel() { JPanel viewPanel = new JPanel(); viewPanel.setLayout(new GridBagLayout()); GridBagConstraints c = new GridBagConstraints(); c.fill = GridBagConstraints.HORIZONTAL ; c.gridy = 0; c.weightx = 1; c.weighty = 0.3; viewPanel.add(initCreatorLabel(), c); c.gridy++; viewPanel.add(this.initNoteTextArea(), c); c.fill = GridBagConstraints.NONE; c.anchor = GridBagConstraints.WEST; c.gridy++; viewPanel.add(initEditorLabel(), c); c.gridx++; c.anchor = GridBagConstraints.EAST; viewPanel.add(initEditButton(), c); return viewPanel; } private JLabel initCreatorLabel() { DateFormat formatter = new SimpleDateFormat("yyyy-MM-dd"); if (note != null) { String noteBy = "Note by " + note.getCreator(); String noteCreated = formatter.format(note.getDateCreated()); JLabel creatorLabel = new JLabel(noteBy + " @ " + noteCreated); creatorLabel.setAlignmentX(JLabel.LEFT_ALIGNMENT); return creatorLabel; } else { System.out.println("NOTE IS NULL"); return null; } } private JScrollPane initNoteTextArea() { // -- Setup the notes area. this.viewTextArea = new JTextArea(note.getContents()); viewTextArea.setEditable(false); viewTextArea.setLineWrap(true); viewTextArea.setWrapStyleWord(true); JScrollPane scrollPane = new JScrollPane(viewTextArea); scrollPane.setAlignmentX(JScrollPane.LEFT_ALIGNMENT); return scrollPane; } private JLabel initEditorLabel() { // -- Setup the edited by label. JLabel editorLabel = new JLabel(" -- Last edited by " + note.getLastEdited() + " at " + note.getDateModified()); editorLabel.setAlignmentX(Component.LEFT_ALIGNMENT); return editorLabel; } private JButton initEditButton() { final CardLayout l = this.cardLayout; final JPanel p = this; ActionListener ar = new ActionListener() { @Override public void actionPerformed(ActionEvent e) { l.next(p); } }; JButton editButton = new JButton("Edit"); editButton.setPreferredSize(new Dimension(62,26)); editButton.addActionListener(ar); return editButton; } //</editor-fold> // <editor-fold defaultstate="collapsed" desc="Grow Width When Resized"> @Override public Dimension getPreferredSize() { int fw = this.getParent().getSize().width; int fh = super.getPreferredSize().height; return new Dimension(fw,fh); } //</editor-fold> }

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• Cloud to On-Premise Connectivity Patterns

  - by Rajesh Raheja

  Do you have a requirement to convert an Opportunity in Salesforce.com to an Order/Quote in Oracle E-Business Suite? Or maybe you want the creation of an Oracle RightNow Incident to trigger an on-premise Oracle E-Business Suite Service Request creation for RMA and Field Scheduling? If so, read on. In a previous blog post, I discussed integrating TO cloud applications, however the use cases above are the reverse i.e. receiving data FROM cloud applications (SaaS) TO on-premise applications/databases that sit behind a firewall. Oracle SOA Suite is assumed to be on-premise with with Oracle Service Bus as the mediation and virtualization layer. The main considerations for the patterns are are security i.e. shielding enterprise resources; and scalability i.e. minimizing firewall latency. Let me use an analogy to help visualize the patterns: the on-premise system is your home - with your most valuable possessions - and the SaaS app is your favorite on-line store which regularly ships (inbound calls) various types of parcels/items (message types/service operations). You need the items at home (on-premise) but want to safe guard against misguided elements of society (internet threats) who may masquerade as postal workers and vandalize property (denial of service?). Let's look at the patterns. Pattern: Pull from Cloud The on-premise system polls from the SaaS apps and picks up the message instead of having it delivered. This may be done using Oracle RightNow Object Query Language or SOAP APIs. This is particularly suited for certain integration approaches wherein messages are trickling in, can be centralized and batched e.g. retrieving event notifications on an hourly schedule from the Oracle Messaging Service. To compare this pattern with the home analogy, you are avoiding any deliveries to your home and instead go to the post office/UPS/Fedex store to pick up your parcel. Every time. Pros: On-premise assets not exposed to the Internet, firewall issues avoided by only initiating outbound connections Cons: Polling mechanisms may affect performance, may not satisfy near real-time requirements Pattern: Open Firewall Ports The on-premise system exposes the web services that needs to be invoked by the cloud application. This requires opening up firewall ports, routing calls to the appropriate internal services behind the firewall. Fusion Applications uses this pattern, and auto-provisions the services on the various virtual hosts to secure the topology. This works well for service integration, but may not suffice for large volume data integration. Using the home analogy, you have now decided to receive parcels instead of going to the post office every time. A door mail slot cut out allows the postman can drop small parcels, but there is still concern about cutting new holes for larger packages. Pros: optimal pattern for near real-time needs, simpler administration once the service is provisioned Cons: Needs firewall ports to be opened up for new services, may not suffice for batch integration requiring direct database access Pattern: Virtual Private Networking The on-premise network is "extended" to the cloud (or an intermediary on-demand / managed service offering) using Virtual Private Networking (VPN) so that messages are delivered to the on-premise system in a trusted channel. Using the home analogy, you entrust a set of keys with a neighbor or property manager who receives the packages, and then drops it inside your home. Pros: Individual firewall ports don't need to be opened, more suited for high scalability needs, can support large volume data integration, easier management of one connection vs a multitude of open ports Cons: VPN setup, specific hardware support, requires cloud provider to support virtual private computing Pattern: Reverse Proxy / API Gateway The on-premise system uses a reverse proxy "API gateway" software on the DMZ to receive messages. The reverse proxy can be implemented using various mechanisms e.g. Oracle API Gateway provides firewall and proxy services along with comprehensive security, auditing, throttling benefits. If a firewall already exists, then Oracle Service Bus or Oracle HTTP Server virtual hosts can provide reverse proxy implementations on the DMZ. Custom built implementations are also possible if specific functionality (such as message store-n-forward) is needed. In the home analogy, this pattern sits in between cutting mail slots and handing over keys. Instead, you install (and maintain) a mailbox in your home premises outside your door. The post office delivers the parcels in your mailbox, from where you can securely retrieve it. Pros: Very secure, very flexible Cons: Introduces a new software component, needs DMZ deployment and management Pattern: On-Premise Agent (Tunneling) A light weight "agent" software sits behind the firewall and initiates the communication with the cloud, thereby avoiding firewall issues. It then maintains a bi-directional connection either with pull or push based approaches using (or abusing, depending on your viewpoint) the HTTP protocol. Programming protocols such as Comet, WebSockets, HTTP CONNECT, HTTP SSH Tunneling etc. are possible implementation options. In the home analogy, a resident receives the parcel from the postal worker by opening the door, however you still take precautions with chain locks and package inspections. Pros: Light weight software, IT doesn't need to setup anything Cons: May bypass critical firewall checks e.g. virus scans, separate software download, proliferation of non-IT managed software Conclusion The patterns above are some of the most commonly encountered ones for cloud to on-premise integration. Selecting the right pattern for your project involves looking at your scalability needs, security restrictions, sync vs asynchronous implementation, near real-time vs batch expectations, cloud provider capabilities, budget, and more. In some cases, the basic "Pull from Cloud" may be acceptable, whereas in others, an extensive VPN topology may be well justified. For more details on the Oracle cloud integration strategy, download this white paper.

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• Cloud to On-Premise Connectivity Patterns

  - by Rajesh Raheja

  Do you have a requirement to convert an Opportunity in Salesforce.com to an Order/Quote in Oracle E-Business Suite? Or maybe you want the creation of an Oracle RightNow Incident to trigger an on-premise Oracle E-Business Suite Service Request creation for RMA and Field Scheduling? If so, read on. In a previous blog post, I discussed integrating TO cloud applications, however the use cases above are the reverse i.e. receiving data FROM cloud applications (SaaS) TO on-premise applications/databases that sit behind a firewall. Oracle SOA Suite is assumed to be on-premise with with Oracle Service Bus as the mediation and virtualization layer. The main considerations for the patterns are are security i.e. shielding enterprise resources; and scalability i.e. minimizing firewall latency. Let me use an analogy to help visualize the patterns: the on-premise system is your home - with your most valuable possessions - and the SaaS app is your favorite on-line store which regularly ships (inbound calls) various types of parcels/items (message types/service operations). You need the items at home (on-premise) but want to safe guard against misguided elements of society (internet threats) who may masquerade as postal workers and vandalize property (denial of service?). Let's look at the patterns. Pattern: Pull from Cloud The on-premise system polls from the SaaS apps and picks up the message instead of having it delivered. This may be done using Oracle RightNow Object Query Language or SOAP APIs. This is particularly suited for certain integration approaches wherein messages are trickling in, can be centralized and batched e.g. retrieving event notifications on an hourly schedule from the Oracle Messaging Service. To compare this pattern with the home analogy, you are avoiding any deliveries to your home and instead go to the post office/UPS/Fedex store to pick up your parcel. Every time. Pros: On-premise assets not exposed to the Internet, firewall issues avoided by only initiating outbound connections Cons: Polling mechanisms may affect performance, may not satisfy near real-time requirements Pattern: Open Firewall Ports The on-premise system exposes the web services that needs to be invoked by the cloud application. This requires opening up firewall ports, routing calls to the appropriate internal services behind the firewall. Fusion Applications uses this pattern, and auto-provisions the services on the various virtual hosts to secure the topology. This works well for service integration, but may not suffice for large volume data integration. Using the home analogy, you have now decided to receive parcels instead of going to the post office every time. A door mail slot cut out allows the postman can drop small parcels, but there is still concern about cutting new holes for larger packages. Pros: optimal pattern for near real-time needs, simpler administration once the service is provisioned Cons: Needs firewall ports to be opened up for new services, may not suffice for batch integration requiring direct database access Pattern: Virtual Private Networking The on-premise network is "extended" to the cloud (or an intermediary on-demand / managed service offering) using Virtual Private Networking (VPN) so that messages are delivered to the on-premise system in a trusted channel. Using the home analogy, you entrust a set of keys with a neighbor or property manager who receives the packages, and then drops it inside your home. Pros: Individual firewall ports don't need to be opened, more suited for high scalability needs, can support large volume data integration, easier management of one connection vs a multitude of open ports Cons: VPN setup, specific hardware support, requires cloud provider to support virtual private computing Pattern: Reverse Proxy / API Gateway The on-premise system uses a reverse proxy "API gateway" software on the DMZ to receive messages. The reverse proxy can be implemented using various mechanisms e.g. Oracle API Gateway provides firewall and proxy services along with comprehensive security, auditing, throttling benefits. If a firewall already exists, then Oracle Service Bus or Oracle HTTP Server virtual hosts can provide reverse proxy implementations on the DMZ. Custom built implementations are also possible if specific functionality (such as message store-n-forward) is needed. In the home analogy, this pattern sits in between cutting mail slots and handing over keys. Instead, you install (and maintain) a mailbox in your home premises outside your door. The post office delivers the parcels in your mailbox, from where you can securely retrieve it. Pros: Very secure, very flexible Cons: Introduces a new software component, needs DMZ deployment and management Pattern: On-Premise Agent (Tunneling) A light weight "agent" software sits behind the firewall and initiates the communication with the cloud, thereby avoiding firewall issues. It then maintains a bi-directional connection either with pull or push based approaches using (or abusing, depending on your viewpoint) the HTTP protocol. Programming protocols such as Comet, WebSockets, HTTP CONNECT, HTTP SSH Tunneling etc. are possible implementation options. In the home analogy, a resident receives the parcel from the postal worker by opening the door, however you still take precautions with chain locks and package inspections. Pros: Light weight software, IT doesn't need to setup anything Cons: May bypass critical firewall checks e.g. virus scans, separate software download, proliferation of non-IT managed software Conclusion The patterns above are some of the most commonly encountered ones for cloud to on-premise integration. Selecting the right pattern for your project involves looking at your scalability needs, security restrictions, sync vs asynchronous implementation, near real-time vs batch expectations, cloud provider capabilities, budget, and more. In some cases, the basic "Pull from Cloud" may be acceptable, whereas in others, an extensive VPN topology may be well justified. For more details on the Oracle cloud integration strategy, download this white paper.

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• How do I organize a GUI application for passing around events and for setting up reads from a shared resource

  - by Savanni D'Gerinel

  My tools involved here are GTK and Haskell. My questions are probably pretty trivial for anyone who has done significant GUI work, but I've been off in the equivalent of CGI applications for my whole career. I'm building an application that displays tabular data, displays the same data in a graph form, and has an edit field for both entering new data and for editing existing data. After asking about sharing resources, I decided that all of the data involved will be stored in an MVar so that every component can just read the current state from the MVar. All of that works, but now it is time for me to rearrange the application so that it can be interactive. With that in mind, I have three widgets: a TextView (for editing), a TreeView (for displaying the data), and a DrawingArea (for displaying the data as a graph). I THINK I need to do two things, and the core of my question is, are these the right things, or is there a better way. Thing the first: All event handlers, those functions that will be called any time a redisplay is needed, need to be written at a high level and then passed into the function that actually constructs the widget to begin with. For instance: drawStatData :: DrawingArea -> MVar Core.ST -> (Core.ST -> SetRepWorkout.WorkoutStore) -> IO () createStatView :: (DrawingArea -> IO ()) -> IO VBox createUI :: MVar Core.ST -> (Core.ST -> SetRepWorkout.WorkoutStore) -> IO HBox createUI storeMVar field = do graphs <- createStatView (\area -> drawStatData area storeMVar field) hbox <- hBoxNew False 10 boxPackStart hbox graphs PackNatural 0 return hbox In this case, createStatView builds up a VBox that contains a DrawingArea to graph the data and potentially other widgets. It attaches drawStatData to the realize and exposeEvent events for the DrawingArea. I would do something similar for the TreeView, but I am not completely sure what since I have not yet done it and what I am thinking of would involve replacing the TreeModel every time the TreeView needs to be updated. My alternative to the above would be... drawStatData :: DrawingArea -> MVar Core.ST -> (Core.ST -> SetRepWorkout.WorkoutStore) -> IO () createStatView :: IO (VBox, DrawingArea) ... but in this case, I would arrange createUI like so: createUI :: MVar Core.ST -> (Core.ST -> SetRepWorkout.WorkoutStore) -> IO HBox createUI storeMVar field = do (graphbox, graph) <- createStatView (\area -> drawStatData area storeMVar field) hbox <- hBoxNew False 10 boxPackStart hbox graphs PackNatural 0 on graph realize (drawStatData graph storeMVar field) on graph exposeEvent (do liftIO $ drawStatData graph storeMVar field return ()) return hbox I'm not sure which is better, but that does lead me to... Thing the second: it will be necessary for me to rig up an event system so that various events can send signals all the way to my widgets. I'm going to need a mediator of some kind to pass events around and to translate application-semantic events to the actual events that my widgets respond to. Is it better for me to pass my addressable widgets up the call stack to the level where the mediator lives, or to pass the mediator down the call stack and have the widgets register directly with it? So, in summary, my two questions: 1) pass widgets up the call stack to a global mediator, or pass the global mediator down and have the widgets register themselves to it? 2) pass my redraw functions to the builders and have the builders attach the redraw functions to the constructed widgets, or pass the constructed widgets back and have a higher level attach the redraw functions (and potentially link some widgets together)? Okay, and... 3) Books or wikis about GUI application architecture, preferably coherent architectures where people aren't arguing about minute details? The application in its current form (displays data but does not write data or allow for much interaction) is available at https://bitbucket.org/savannidgerinel/fitness . You can run the application by going to the root directory and typing runhaskell -isrc src/Main.hs data/ or... cabal build dist/build/fitness/fitness data/ You may need to install libraries, but cabal should tell you which ones.

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• ADF Business Components

  - by Arda Eralp

  ADF Business Components and JDeveloper simplify the development, delivery, and customization of business applications for the Java EE platform. With ADF Business Components, developers aren't required to write the application infrastructure code required by the typical Java EE application to: Connect to the database Retrieve data Lock database records Manage transactions   ADF Business Components addresses these tasks through its library of reusable software components and through the supporting design time facilities in JDeveloper. Most importantly, developers save time using ADF Business Components since the JDeveloper design time makes typical development tasks entirely declarative. In particular, JDeveloper supports declarative development with ADF Business Components to: Author and test business logic in components which automatically integrate with databases Reuse business logic through multiple SQL-based views of data, supporting different application tasks Access and update the views from browser, desktop, mobile, and web service clients Customize application functionality in layers without requiring modification of the delivered application The goal of ADF Business Components is to make the business services developer more productive.   ADF Business Components provides a foundation of Java classes that allow your business-tier application components to leverage the functionality provided in the following areas: Simplifying Data Access Design a data model for client displays, including only necessary data Include master-detail hierarchies of any complexity as part of the data model Implement end-user Query-by-Example data filtering without code Automatically coordinate data model changes with business services layer Automatically validate and save any changes to the database   Enforcing Business Domain Validation and Business Logic Declaratively enforce required fields, primary key uniqueness, data precision-scale, and foreign key references Easily capture and enforce both simple and complex business rules, programmatically or declaratively, with multilevel validation support Navigate relationships between business domain objects and enforce constraints related to compound components   Supporting Sophisticated UIs with Multipage Units of Work Automatically reflect changes made by business service application logic in the user interface Retrieve reference information from related tables, and automatically maintain the information when the user changes foreign-key values Simplify multistep web-based business transactions with automatic web-tier state management Handle images, video, sound, and documents without having to use code Synchronize pending data changes across multiple views of data Consistently apply prompts, tooltips, format masks, and error messages in any application Define custom metadata for any business components to support metadata-driven user interface or application functionality Add dynamic attributes at runtime to simplify per-row state management   Implementing High-Performance Service-Oriented Architecture Support highly functional web service interfaces for business integration without writing code Enforce best-practice interface-based programming style Simplify application security with automatic JAAS integration and audit maintenance "Write once, run anywhere": use the same business service as plain Java class, EJB session bean, or web service   Streamlining Application Customization Extend component functionality after delivery without modifying source code Globally substitute delivered components with extended ones without modifying the application   ADF Business Components implements the business service through the following set of cooperating components: Entity object An entity object represents a row in a database table and simplifies modifying its data by handling all data manipulation language (DML) operations for you. These are basically your 1 to 1 representation of a database table. Each table in the database will have 1 and only 1 EO. The EO contains the mapping between columns and attributes. EO's also contain the business logic and validation. These are you core data services. They are responsible for updating, inserting and deleting records. The Attributes tab displays the actual mapping between attributes and columns, the mapping has following fields: Name : contains the name of the attribute we expose in our data model. Type : defines the data type of the attribute in our application. Column : specifies the column to which we want to map the attribute with Column Type : contains the type of the column in the database   View object A view object represents a SQL query. You use the full power of the familiar SQL language to join, filter, sort, and aggregate data into exactly the shape required by the end-user task. The attributes in the View Objects are actually coming from the Entity Object. In the end the VO will generate a query but you basically build a VO by selecting which EO need to participate in the VO and which attributes of those EO you want to use. That's why you have the Entity Usage column so you can see the relation between VO and EO. In the query tab you can clearly see the query that will be generated for the VO. At this stage we don't need it and just use it for information purpose. In later stages we might use it. Application module An application module is the controller of your data layer. It is responsible for keeping hold of the transaction. It exposes the data model to the view layer. You expose the VO's through the Application Module. This is the abstraction of your data layer which you want to show to the outside word.It defines an updatable data model and top-level procedures and functions (called service methods) related to a logical unit of work related to an end-user task. While the base components handle all the common cases through built-in behavior, customization is always possible and the default behavior provided by the base components can be easily overridden or augmented. When you create EO's, a foreign key will be translated into an association in our model. It defines the type of relation and who is the master and child as well as how the visibility of the association looks like. A similar concept exists to identify relations between view objects. These are called view links. These are almost identical as association except that a view link is based upon attributes defined in the view object. It can also be based upon an association. Here's a short summary: Entity Objects: representations of tables Association: Relations between EO's. Representations of foreign keys View Objects: Logical model View Links: Relationships between view objects Application Model: interface to your application  

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• How You Helped Shape Java EE 7...

  - by reza_rahman

  I have been working with the JCP in various roles since EJB 3/Java EE 5 (much of it on my own time), eventually culminating in my decision to accept my current role at Oracle (despite it's inevitable set of unique challenges, a role I find by and large positive and fulfilling). During these years, it has always been clear to me that pretty much everyone in the JCP genuinely cares about openness, feedback and developer participation. Perhaps the most visible sign to date of this high regard for grassroots level input is a survey on Java EE 7 gathered a few months ago. The survey was designed to get open feedback on a number of critical issues central to the Java EE 7 umbrella specification including what APIs to include in the standard. When we started the survey, I don't think anyone was certain what the level of participation from developers would really be. I also think everyone was pleasantly surprised that a large number of developers (around 1100) took the time out to vote on these very important issues that could impact their own professional life. And it wasn't just a matter of the quantity of responses. I was particularly impressed with the quality of the comments made through the survey (some of which I'll try to do justice to below). With Java EE 7 under our belt and the horizons for Java EE 8 emerging, this is a good time to thank everyone that took the survey once again for their thoughts and let you know what the impact of your voice actually was. As an aside, you may be happy to know that we are working hard behind the scenes to try to put together a similar survey to help kick off the agenda for Java EE 8 (although this is by no means certain). I'll break things down by the questions asked in the survey, the responses and the resulting change in the specification. APIs to Add to Java EE 7 Full/Web Profile The first question in the survey asked which of four new candidate APIs (WebSocket, JSON-P, JBatch and JCache) should be added to the Java EE 7 Full and Web profile respectively. Developers by and large wanted all the new APIs added to the full platform. The comments expressed particularly strong support for WebSocket and JCache. Others expressed dissatisfaction over the lack of a JSON binding (as opposed to JSON processing) API. WebSocket, JSON-P and JBatch are now part of Java EE 7. In addition, the long-awaited Java EE Concurrency Utilities API was also included in the Full Profile. Unfortunately, JCache was not finalized in time for Java EE 7 and the decision was made not to hold up the Java EE release any longer. JCache continues to move forward strongly and will very likely be included in Java EE 8 (it will be available much sooner than Java EE 8 to boot). An emergent standard for JSON-B is also a strong possibility for Java EE 8. When it came to the Web Profile, developers were supportive of adding WebSocket and JSON-P, but not JBatch and JCache. Both WebSocket and JSON-P are now part of the Web Profile, now also including the already popular JAX-RS API. Enabling CDI by Default The second question asked whether CDI should be enabled in Java EE by default. The overwhelming majority of developers supported the default enablement of CDI. In addition, developers expressed a desire for better CDI/Java EE alignment (with regards to EJB and JSF in particular). Some developers expressed legitimate concerns over the performance implications of enabling CDI globally as well as the potential conflict with other JSR 330 implementations like Spring and Guice. CDI is enabled by default in Java EE 7. Respecting the legitimate concerns, CDI 1.1 was very careful to add additional controls around component scanning. While a lot of work was done in Java EE 6 and Java EE 7 around CDI alignment, further alignment is under serious consideration for Java EE 8. Consistent Usage of @Inject The third question was around using CDI/JSR 330 @Inject consistently vs. allowing JSRs to create their own injection annotations (e.g. @BatchContext). A majority of developers wanted consistent usage of @Inject. The comments again reflected a strong desire for CDI/Java EE alignment. A lot of emphasis in Java EE 7 was put into using @Inject consistently. For example, the JBatch specification is focused on using @Inject wherever possible. JAX-RS remains an exception with it's existing custom injection annotations. However, the JAX-RS specification leads understand the importance of eventual convergence, hopefully in Java EE 8. Expanding the Use of @Stereotype The fourth question was about expanding CDI @Stereotype to cover annotations across Java EE beyond just CDI. A solid majority of developers supported the idea of making @Stereotype more universal in Java EE. The comments maintained the general theme of strong support for CDI/Java EE alignment Unfortunately, there was not enough time and resources in Java EE 7 to implement this fairly pervasive feature. However, it remains a serious consideration for Java EE 8. Expanding Interceptor Use The final set of questions was about expanding interceptors further across Java EE. Developers strongly supported the concept. Along with injection, interceptors are now supported across all Java EE 7 components including Servlets, Filters, Listeners, JAX-WS endpoints, JAX-RS resources, WebSocket endpoints and so on. I hope you are encouraged by how your input to the survey helped shape Java EE 7 and continues to shape Java EE 8. Participating in these sorts of surveys is of course just one way of contributing to Java EE. Another great way to stay involved is the Adopt-A-JSR Program. A large number of developers are already participating through their local JUGs. You could of course become a Java EE JSR expert group member or observer. You should stay tuned to The Aquarium for the progress of Java EE 8 JSRs if that's something you want to look into...

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• LINQ and ArcObjects

  - by Marko Apfel

  Motivation LINQ (language integrated query) is a component of the Microsoft. NET Framework since version 3.5. It allows a SQL-like query to various data sources such as SQL, XML etc. Like SQL also LINQ to SQL provides a declarative notation of problem solving – i.e. you don’t need describe in detail how a task could be solved, you describe what to be solved at all. This frees the developer from error-prone iterator constructs. Ideally, of course, would be to access features with this way. Then this construct is conceivable: var largeFeatures = from feature in features where (feature.GetValue("SHAPE_Area").ToDouble() > 3000) select feature; or its equivalent as a lambda expression: var largeFeatures = features.Where(feature => (feature.GetValue("SHAPE_Area").ToDouble() > 3000)); This requires an appropriate provider, which manages the corresponding iterator logic. This is easier than you might think at first sight - you have to deliver only the desired entities as IEnumerable<IFeature>. LINQ automatically establishes a state machine in the background, whose execution is delayed (deferred execution) - when you are really request entities (foreach, Count (), ToList (), ..) an instantiation processing takes place, although it was already created at a completely different place. Especially in multiple iteration through entities in the first debuggings you are rubbing your eyes when the execution pointer jumps magically back in the iterator logic. Realization A very concise logic for constructing IEnumerable<IFeature> can be achieved by running through a IFeatureCursor. You return each feature via yield. For an easier usage I have put the logic in an extension method Getfeatures() for IFeatureClass: public static IEnumerable<IFeature> GetFeatures(this IFeatureClass featureClass, IQueryFilter queryFilter, RecyclingPolicy policy) { IFeatureCursor featureCursor = featureClass.Search(queryFilter, RecyclingPolicy.Recycle == policy); IFeature feature; while (null != (feature = featureCursor.NextFeature())) { yield return feature; } //this is skipped in unit tests with cursor-mock if (Marshal.IsComObject(featureCursor)) { Marshal.ReleaseComObject(featureCursor); } } So you can now easily generate the IEnumerable<IFeature>: IEnumerable<IFeature> features = _featureClass.GetFeatures(RecyclingPolicy.DoNotRecycle); You have to be careful with the recycling cursor. After a delayed execution in the same context it is not a good idea to re-iterated on the features. In this case only the content of the last (recycled) features is provided and all the features are the same in the second set. Therefore, this expression would be critical: largeFeatures.ToList(). ForEach(feature => Debug.WriteLine(feature.OID)); because ToList() iterates once through the list and so the the cursor was once moved through the features. So the extension method ForEach() always delivers the same feature. In such situations, you must not use a recycling cursor. Repeated executions of ForEach() is not a problem, because for every time the state machine is re-instantiated and thus the cursor runs again - that's the magic already mentioned above. Perspective Now you can also go one step further and realize your own implementation for the interface IEnumerable<IFeature>. This requires that only the method and property to access the enumerator have to be programmed. In the enumerator himself in the Reset() method you organize the re-executing of the search. This could be archived with an appropriate delegate in the constructor: new FeatureEnumerator<IFeatureclass>(_featureClass, featureClass => featureClass.Search(_filter, isRecyclingCursor)); which is called in Reset(): public void Reset() { _featureCursor = _resetCursor(_t); } In this manner, enumerators for completely different scenarios could be implemented, which are used on the client side completely identical like described above. Thus cursors, selection sets, etc. merge into a single matter and the reusability of code is increasing immensely. On top of that in automated unit tests an IEnumerable could be mocked very easily - a major step towards better software quality. Conclusion Nevertheless, caution should be exercised with these constructs in performance-relevant queries. Because of managing a state machine in the background, a lot of overhead is created. The processing costs additional time - about 20 to 100 percent. In addition, working without a recycling cursor is fast a performance gap. However declarative LINQ code is much more elegant, flawless and easy to maintain than manually iterating, compare and establish a list of results. The code size is reduced according to experience an average of 75 to 90 percent! So I like to wait a few milliseconds longer. As so often it has to be balanced between maintainability and performance - which for me is gaining in priority maintainability. In times of multi-core processors, the processing time of most business processes is anyway not dominated by code execution but by waiting for user input. Demo source code The source code for this prototype with several unit tests, you can download here: https://github.com/esride-apf/Linq2ArcObjects. .

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• SOA, Governance, and Drugs

  Why is IT governance important in service oriented architecture (SOA)? IT Governance provides a framework for making appropriate decisions based on company guidelines and accepted standards. This framework also outlines each stakeholder’s responsibilities and authority when making important architectural or design decisions. Furthermore, this framework of governance defines parameters and constraints that are used to give context and perspective when making decisions. The use of governance as it applies to SOA ensures that specific design principles and patterns are used when developing and maintaining services. When governance is consistently applied systems the following benefits are achieved according to Anne Thomas Manes in 2010. Governance makes sure that services conform to standard interface patterns, common data modeling practices, and promotes the incorporation of existing system functionality by building on top of other available services across a system. Governance defines development standards based on proven design principles and patterns that promote reuse and composition. Governance provides developers a set of proven design principles, standards and practices that promote the reduction in system based component dependencies.  By following these guidelines, individual components will be easier to maintain. For me personally, I am a fan of IT governance, and feel that it valuable part of any corporate IT department. However, depending on how it is implemented can really affect the value of using IT governance.  Companies need to find a way to ensure that governance does not become extreme in its policies and procedures. I know for me personally, I would really dislike working under a completely totalitarian or laissez-faire version of governance. Developers need to be able to be creative in their designs and too much governance can really impede the design process and prevent the most optimal design from being developed. On the other hand, with no governance enforced, no standards will be followed and accepted design patterns will be ignored. I have personally had to spend a lot of time working on this particular scenario and I have found that the concept of code reuse and composition is almost nonexistent.  Based on this, too much time and money is wasted on redeveloping existing aspects of an application that already exist within the system as a whole. I think moving forward we will see a staggered form of IT governance, regardless if it is for SOA or IT in general.  Depending on the size of a company and the size of its IT department,  I can see IT governance as a layered approach in that the top layer will be defined by enterprise architects that focus on abstract concepts pertaining to high level design, general  guidelines, acceptable best practices, and recommended design patterns.  The next layer will be defined by solution architects or department managers that further expand on abstracted guidelines defined by the enterprise architects. This layer will contain further definitions as to when various design patterns, coding standards, and best practices are to be applied based on the context of the solutions that are being developed by the department. The final layer will be defined by the system designer or a solutions architect assed to a project in that they will define what design patterns will be used in a solution, naming conventions, as well as outline how a system will function based on the best practices defined by the previous layers. This layered approach allows for IT departments to be flexible in that system designers have creative leeway in designing solutions to meet the needs of the business, but they must operate within the confines of the abstracted IT governance guidelines.  A real world example of this can be seen in the United States as it pertains to governance of the people in that the US government defines rules and regulations in the abstract and then the state governments take these guidelines and applies them based on the will of the people in each individual state. Furthermore, the county or city governments are the ones that actually enforce these rules based on how they are interpreted by local community.  To further define my example, the United States government defines that marijuana is illegal. Each individual state has the option to determine this regulation as it wishes in that the state of Florida determines that all uses of the drug are illegal, but the state of California legally allows the use of marijuana for medicinal purposes only. Based on these accepted practices each local government enforces these rules in that a police officer will arrest anyone in the state of Florida for having this drug on them if they walk down the street, but in California if a person has a medical prescription for the drug they will not get arrested.  REFERENCESThomas Manes, Anne. (2010). Understanding SOA Governance: http://www.soamag.com/I40/0610-2.php

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• Concurrency Utilities for Java EE Early Draft (JSR 236)

  - by arungupta

  Concurrency Utilities for Java EE is being worked as JSR 236 and has released an Early Draft. It provides concurrency capabilities to Java EE application components without compromising container integrity. Simple (common) and advanced concurrency patterns are easily supported without sacrificing usability. Using Java SE concurrency utilities such as java.util.concurrent API, java.lang.Thread and java.util.Timer in a Java EE application component such as EJB or Servlet are problematic since the container and server have no knowledge of these resources. JSR 236 enables concurrency largely by extending the Concurrency Utilities API developed under JSR-166. This also allows a consistency between Java SE and Java EE concurrency programming model. There are four main programming interfaces available: ManagedExecutorService ManagedScheduledExecutorService ContextService ManagedThreadFactory ManagedExecutorService is a managed version of java.util.concurrent.ExecutorService. The implementations of this interface are provided by the container and accessible using JNDI reference: <resource-env-ref>  <resource-env-ref-name>    concurrent/BatchExecutor  </resource-env-ref-name>  <resource-env-ref-type>    javax.enterprise.concurrent.ManagedExecutorService  </resource-env-ref-type><resource-env-ref> and available as: @Resource(name="concurrent/BatchExecutor")ManagedExecutorService executor; Its recommended to bind the JNDI references in the java:comp/env/concurrent subcontext. The asynchronous tasks that need to be executed need to implement java.lang.Runnable or java.util.concurrent.Callable interface as: public class MyTask implements Runnable { public void run() { // business logic goes here }} OR public class MyTask2 implements Callable<Date> {  public Date call() { // business logic goes here   }} The task is then submitted to the executor using one of the submit method that return a Future instance. The Future represents the result of the task and can also be used to check if the task is complete or wait for its completion. Future<String> future = executor.submit(new MyTask(), String.class);. . .String result = future.get(); Another example to submit tasks is: class MyTask implements Callback<Long> { . . . }class MyTask2 implements Callback<Date> { . . . }ArrayList<Callable> tasks = new ArrayList<();tasks.add(new MyTask());tasks.add(new MyTask2());List<Future<Object>> result = executor.invokeAll(tasks); The ManagedExecutorService may be configured for different properties such as: Hung Task Threshold: Time in milliseconds that a task can execute before it is considered hung Pool Info Core Size: Number of threads to keep alive Maximum Size: Maximum number of threads allowed in the pool Keep Alive: Time to allow threads to remain idle when # of threads > Core Size Work Queue Capacity: # of tasks that can be stored in inbound buffer Thread Use: Application intend to run short vs long-running tasks, accordingly pooled or daemon threads are picked ManagedScheduledExecutorService adds delay and periodic task running capabilities to ManagedExecutorService. The implementations of this interface are provided by the container and accessible using JNDI reference: <resource-env-ref>  <resource-env-ref-name>    concurrent/BatchExecutor  </resource-env-ref-name>  <resource-env-ref-type>    javax.enterprise.concurrent.ManagedExecutorService  </resource-env-ref-type><resource-env-ref> and available as: @Resource(name="concurrent/timedExecutor")ManagedExecutorService executor; And then the tasks are submitted using submit, invokeXXX or scheduleXXX methods. ScheduledFuture<?> future = executor.schedule(new MyTask(), 5, TimeUnit.SECONDS); This will create and execute a one-shot action that becomes enabled after 5 seconds of delay. More control is possible using one of the newly added methods: MyTaskListener implements ManagedTaskListener {  public void taskStarting(...) { . . . }  public void taskSubmitted(...) { . . . }  public void taskDone(...) { . . . }  public void taskAborted(...) { . . . } }ScheduledFuture<?> future = executor.schedule(new MyTask(), 5, TimeUnit.SECONDS, new MyTaskListener()); Here, ManagedTaskListener is used to monitor the state of a task's future. ManagedThreadFactory provides a method for creating threads for execution in a managed environment. A simple usage is: @Resource(name="concurrent/myThreadFactory")ManagedThreadFactory factory;. . .Thread thread = factory.newThread(new Runnable() { . . . }); concurrent/myThreadFactory is a JNDI resource. There is lot of interesting content in the Early Draft, download it, and read yourself. The implementation will be made available soon and also be integrated in GlassFish 4 as well. Some references for further exploring ... Javadoc Early Draft Specification concurrency-ee-spec.java.net [email protected]

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• ComboBox Data Binding

  - by Geertjan

  Let's create a databound combobox, levering MVC in a desktop application. The result will be a combobox, provided by the NetBeans ChoiceView, that displays data retrieved from a database: What follows is not much different from the NetBeans Platform CRUD Application Tutorial and you're advised to consult that document if anything that follows isn't clear enough. One kind of interesting thing about the instructions that follow is that it shows that you're able to create an application where each element of the MVC architecture can be located within a separate module: Start by creating a new NetBeans Platform application named "MyApplication". Model We're going to start by generating JPA entity classes from a database connection. In the New Project wizard, choose "Java Class Library". Click Next. Name the Java Class Library "MyEntities". Click Finish. Right-click the MyEntities project, choose New, and then select "Entity Classes from Database". Work through the wizard, selecting the tables of interest from your database, and naming the package "entities". Click Finish. Now a JPA entity is created for each of the selected tables. In the Project Properties dialog of the project, choose "Copy Dependent Libraries" in the Packaging panel. Build the project. In your project's "dist" folder (visible in the Files window), you'll now see a JAR, together with a "lib" folder that contains the JARs you'll need. In your NetBeans Platform application, create a module named "MyModel", with code name base "org.my.model". Right-click the project, choose Properties, and in the "Libraries" panel, click Add Dependency button in the Wrapped JARs subtab to add all the JARs from the previous step to the module. Also include "derby-client.jar" or the equivalent driver for your database connection to the module. Controler In your NetBeans Platform application, create a module named "MyControler", with code name base "org.my.controler". Right-click the module's Libraries node, in the Projects window, and add a dependency on "Explorer & Property Sheet API". In the MyControler module, create a class with this content: package org.my.controler; import org.openide.explorer.ExplorerManager; public class MyUtils { static ExplorerManager controler; public static ExplorerManager getControler() { if (controler == null) { controler = new ExplorerManager(); } return controler; } } View In your NetBeans Platform application, create a module named "MyView", with code name base "org.my.view".  Create a new Window Component, in "explorer" view, for example, let it open on startup, with class name prefix "MyView". Add dependencies on the Nodes API and on the Explorer & Property Sheet API. Also add dependencies on the "MyModel" module and the "MyControler" module. Before doing so, in the "MyModel" module, make the "entities" package and the "javax.persistence" packages public (in the Libraries panel of the Project Properties dialog) and make the one package that you have in the "MyControler" package public too. Define the top part of the MyViewTopComponent as follows: public final class MyViewTopComponent extends TopComponent implements ExplorerManager.Provider { ExplorerManager controler = MyUtils.getControler(); public MyViewTopComponent() { initComponents(); setName(Bundle.CTL_MyViewTopComponent()); setToolTipText(Bundle.HINT_MyViewTopComponent()); setLayout(new BoxLayout(this, BoxLayout.PAGE_AXIS)); controler.setRootContext(new AbstractNode(Children.create(new ChildFactory<Customer>() { @Override protected boolean createKeys(List list) { EntityManager entityManager = Persistence. createEntityManagerFactory("MyEntitiesPU").createEntityManager(); Query query = entityManager.createNamedQuery("Customer.findAll"); list.addAll(query.getResultList()); return true; } @Override protected Node createNodeForKey(Customer key) { Node customerNode = new AbstractNode(Children.LEAF, Lookups.singleton(key)); customerNode.setDisplayName(key.getName()); return customerNode; } }, true))); controler.addPropertyChangeListener(new PropertyChangeListener() { @Override public void propertyChange(PropertyChangeEvent evt) { Customer selectedCustomer = controler.getSelectedNodes()[0].getLookup().lookup(Customer.class); StatusDisplayer.getDefault().setStatusText(selectedCustomer.getName()); } }); JPanel row1 = new JPanel(new FlowLayout(FlowLayout.LEADING)); row1.add(new JLabel("Customers: ")); row1.add(new ChoiceView()); add(row1); } @Override public ExplorerManager getExplorerManager() { return controler; } ... ... ... Now run the application and you'll see the same as the image with which this blog entry started.

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• Viewing the NetBeans Central Registry (Part 2)

  - by Geertjan

  Jens Hofschröer, who has one of the very best NetBeans Platform blogs (if you more or less understand German), and who wrote, sometime ago, the initial version of the Import Statement Organizer, as well as being the main developer of a great gear design & manufacturing tool on the NetBeans Platform in Aachen, commented on my recent blog entry "Viewing the NetBeans Central Registry", where the root Node of the Central Registry is shown in a BeanTreeView, with the words: "I wrapped that Node in a FilterNode to provide the 'position' attribute and the 'file extension'. All Children are wrapped too. Then I used an OutlineView to show these two properties. Great tool to find wrong layer entries." I asked him for the code he describes above and he sent it to me. He discussed it here in his blog, while all the code involved can be read below. The result is as follows, where you can see that the OutlineView shows information that my simple implementation (via a BeanTreeView) kept hidden: And so here is the definition of the Node. class LayerPropertiesNode extends FilterNode { public LayerPropertiesNode(Node node) { super(node, isFolder(node) ? Children.create(new LayerPropertiesFactory(node), true) : Children.LEAF); } private static boolean isFolder(Node node) { return null != node.getLookup().lookup(DataFolder.class); } @Override public String getDisplayName() { return getLookup().lookup(FileObject.class).getName(); } @Override public Image getIcon(int type) { FileObject fo = getLookup().lookup(FileObject.class); try { DataObject data = DataObject.find(fo); return data.getNodeDelegate().getIcon(type); } catch (DataObjectNotFoundException ex) { Exceptions.printStackTrace(ex); } return super.getIcon(type); } @Override public Image getOpenedIcon(int type) { return getIcon(type); } @Override public PropertySet[] getPropertySets() { Set set = Sheet.createPropertiesSet(); set.put(new PropertySupport.ReadOnly<Integer>( "position", Integer.class, "Position", null) { @Override public Integer getValue() throws IllegalAccessException, InvocationTargetException { FileObject fileEntry = getLookup().lookup(FileObject.class); Integer posValue = (Integer) fileEntry.getAttribute("position"); return posValue != null ? posValue : Integer.valueOf(0); } }); set.put(new PropertySupport.ReadOnly<String>( "ext", String.class, "Extension", null) { @Override public String getValue() throws IllegalAccessException, InvocationTargetException { FileObject fileEntry = getLookup().lookup(FileObject.class); return fileEntry.getExt(); } }); PropertySet[] original = super.getPropertySets(); PropertySet[] withLayer = new PropertySet[original.length + 1]; System.arraycopy(original, 0, withLayer, 0, original.length); withLayer[withLayer.length - 1] = set; return withLayer; } private static class LayerPropertiesFactory extends ChildFactory<FileObject> { private final Node context; public LayerPropertiesFactory(Node context) { this.context = context; } @Override protected boolean createKeys(List<FileObject> list) { FileObject folder = context.getLookup().lookup(FileObject.class); FileObject[] children = folder.getChildren(); List<FileObject> ordered = FileUtil.getOrder(Arrays.asList(children), false); list.addAll(ordered); return true; } @Override protected Node createNodeForKey(FileObject key) { AbstractNode node = new AbstractNode(org.openide.nodes.Children.LEAF, key.isFolder() ? Lookups.fixed(key, DataFolder.findFolder(key)) : Lookups.singleton(key)); return new LayerPropertiesNode(node); } } } Then here is the definition of the Action, which pops up a JPanel, displaying an OutlineView: @ActionID(category = "Tools", id = "de.nigjo.nb.layerview.LayerViewAction") @ActionRegistration(displayName = "#CTL_LayerViewAction") @ActionReferences({ @ActionReference(path = "Menu/Tools", position = 1450, separatorBefore = 1425) }) @Messages("CTL_LayerViewAction=Display XML Layer") public final class LayerViewAction implements ActionListener { @Override public void actionPerformed(ActionEvent e) { try { Node node = DataObject.find(FileUtil.getConfigRoot()).getNodeDelegate(); node = new LayerPropertiesNode(node); node = new FilterNode(node) { @Override public Component getCustomizer() { LayerView view = new LayerView(); view.getExplorerManager().setRootContext(this); return view; } @Override public boolean hasCustomizer() { return true; } }; NodeOperation.getDefault().customize(node); } catch (DataObjectNotFoundException ex) { Exceptions.printStackTrace(ex); } } private static class LayerView extends JPanel implements ExplorerManager.Provider { private final ExplorerManager em; public LayerView() { super(new BorderLayout()); em = new ExplorerManager(); OutlineView view = new OutlineView("entry"); view.addPropertyColumn("position", "Position"); view.addPropertyColumn("ext", "Extension"); add(view); } @Override public ExplorerManager getExplorerManager() { return em; } } }

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• Getting Started with ADF Mobile Sample Apps

  - by Denis T

  Getting Started with ADF Mobile Sample Apps   Installation Steps Install JDeveloper 11.1.2.3.0 from Oracle Technology Network After installing JDeveloper, go to Help menu and select "Check For Updates" and find the ADF Mobile extension and install this. It will require you restart JDeveloper For iOS development, be on a Mac and have Xcode installed. (Currently only Xcode 4.4 is officially supported. Xcode 4.5 support is coming soon) For Android development, have the Android SDK installed. In the JDeveloper Tools menu, select "Preferences". In the Preferences dialog, select ADF Mobile. You can expand it to select configure your Platform preferences for things like the location of Xcode and the Android SDK. In your /jdeveloper/jdev/extensions/oracle.adf.mobile/Samples folder you will find a PublicSamples.zip. Unzip this into the Samples folder so you have all the projects ready to go. Open each of the sample application's .JWS file to open the corresponding workspace. Then from the "Application" menu, select "Deploy" and then select the deployment profile for the platform you wish to deploy to. Try deploying to the simulator/emulator on each platform first because it won't require signing. Note: If you wish to deploy to the Android emulator, it must be running before you start the deployment.   Sample Application Details   Recommended Order of Use Application Name Description 1 HelloWorld The "hello world" application for ADF Mobile, which demonstrates the basic structure of the framework. This basic application has a single application feature that is implemented with a local HTML file. Use this application to ascertain that the development environment is set up correctly to compile and deploy an application. See also Section 4.2.2, "What Happens When You Create an ADF Mobile Application." 2 CompGallery This application is meant to be a runtime application and not necessarily to review the code, though that is available. It serves as an introduction to the ADF Mobile AMX UI components by demonstrating all of these components. Using this application, you can change the attributes of these components at runtime and see the effects of those changes in real time without recompiling and redeploying the application after each change. See generally Chapter 8, "Creating ADF Mobile AMX User Interface." 3 LayoutDemo This application demonstrates the user interface layout and shows how to create the various list and button styles that are commonly used in mobile applications. It also demonstrates how to create the action sheet style of a popup component and how to use various chart and gauge components. See Section 8.3, "Creating and Using UI Components" and Section 8.5, "Providing Data Visualization." Note: This application must be opened from the Samples directory or the Default springboard option must be cleared in the Applications page of the adfmf-application.xml overview editor, then selected again. 4 JavaDemo This application demonstrates how to bind the user interface to Java beans. It also demonstrates how to invoke EL bindings from the Java layer using the supplied utility classes. See also Section 8.10, "Using Event Listeners" and Section 9.2, "Understanding EL Support." 5 Navigation This application demonstrates the various navigation techniques in ADF Mobile, including bounded task flows and routers. It also demonstrates the various page transitions. See also Section 7.2, "Creating Task Flows." Note: This application must be opened from the Samples directory or the Default springboard option must be cleared in the Applications page of the adfmf-application.xml overview editor, then selected again. 6 LifecycleEvents This application implements lifecycle event handlers on the ADF Mobile application itself and its embedded application features. This application shows you where to insert code to enable the applications to perform their own logic at certain points in the lifecycle. See also Section 5.6, "About Lifecycle Event Listeners." Note: iOS, the LifecycleEvents sample application logs data to the Console application, located at Applications-Utilities-Console application. 7 DeviceDemo This application shows you how to use the DeviceFeatures data control to expose such device features as geolocation, e-mail, SMS, and contacts, as well as how to query the device for its properties. See also Section 9.5, "Using the DeviceFeatures Data Control." Note: You must also run this application on an actual device because SMS and some of the device properties do not function on an iOS simulator or Android emulator. 8 GestureDemo This application demonstrates how gestures can be implemented and used in ADF Mobile applications. See also Section 8.4, "Enabling Gestures." 9 StockTracker This application demonstrates how data change events use Java to enable data changes to be reflected in the user interface. It also has a variety of layout use cases, gestures and basic mobile patterns. See also Section 9.7, "Data Change Events."

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• What's New in SGD 5.1?

  - by Fat Bloke

  Oracle announced the latest version of Secure Global Desktop (SGD) this week with 3 major themes: Support for Android devices; Support for Desktop Chrome clients;  Support for Oracle Unified Directory. I'll talk about the new features in a moment, but a bit of context first: Oracle SGD - what, how and why?  Oracle Secure Global Desktop is Oracle's secure remote access product which allows users on almost any device, to access almost any type application which  is hosted in the data center, from almost any location. And it does this by sitting on the edge of the datacenter, between the user and the applications: This is actually a really smart environment for an increasing number of use cases where: Users need mobility of location AND device (i.e. work from anywhere); IT needs to ensure security of applications and data (of course!) The application requires an end-user environment which can't be guaranteed and IT may not own the client platform (e.g. BYOD, working from home, partners or contractors). Oracle has a a specific interest in this of course. As the leading supplier of enterprise applications, many of Oracle's customers, and indeed Oracle itself, fit these criteria. So, as an IT guy rolling out an application to your employees, if one of your apps absolutely needs, say,  IE10 with Java 6 update 32, how can you be sure that the user population has this, especially when they're using their own devices? In the SGD model you, the IT guy, can set up, say, a Windows Server running the exact environment required, and then use SGD to publish this app, without needing to worry any further about the device the end user is using. What's new?  So back to SGD 5.1 and what is new there: Android devices Since we introduced our support for iPad tablets in SGD 5.0 we've had a big demand from customers to extend this to Android tablets too, and so we're pleased to announce that 5.1 supports Android 4.x tablets such as Nexus 7 and 10, and the Galaxy Tab. Here's how it works, with screenshots from my Nexus 7: Simply point your browser to the SGD server URL and login; The workspace is the list of apps that the admin has deemed ok for you to run. You click on an application to run it (here's Excel and Oracle E-Business Suite): There's an extended on-screen keyboard (extended because desktop apps need keys that don't appear on a tablet keyboard such as ctrl, WIndow key, etc) and touch gestures can be mapped to desktop events (such as tap and hold to right click) All in all a pretty nice implementation for Android tablet users. Desktop Chrome Browsers SGD has always been designed around using a browser to access your applications. But traditionally, this has involved using Java to deliver the SGD client component. With HTML5 and Javascript engines becoming so powerful, we thought we'd see how well a pure web client could perform with desktop apps. And the answer was, surprisingly well. So with this release we now offer this additional way of working, which can be enabled by a simple bit of configuration. Here's a Linux desktop running in a tab in Chrome. And if you resize the browser window, the Linux desktop is resized by SGD too. Very cool! Oracle Unified Directory As I mentioned above, a lot of Oracle users already benefit from SGD. And a lot of Oracle customers use Oracle Unified Directory as their Enterprise and Carrier grade user directory. So it makes a lot of sense that SGD now supports this LDAP directory for both Authentication and as a means to determine which users get which applications, e.g. publish the engineering app to the guys in the Development group, but give everyone E-Business Suite to let them do their expenses. Summary With new devices, and faster 4G networking becoming more prevalent, the pressure for businesses to move to a increasingly mobile enterprise is stronger than ever. SGD is good for users, and even better for IT. By offering the user the ability to work from anywhere, and IT the control and security they need, everyone wins with SGD. To try this for yourself, download SGD 5.1 (look under Desktop Virtualization Products) from the Oracle Software Delivery Cloud or if you're an existing customer, get it from My Oracle Support.  -FB 

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• Plagued by multithreaded bugs

  - by koncurrency

  On my new team that I manage, the majority of our code is platform, TCP socket, and http networking code. All C++. Most of it originated from other developers that have left the team. The current developers on the team are very smart, but mostly junior in terms of experience. Our biggest problem: multi-threaded concurrency bugs. Most of our class libraries are written to be asynchronous by use of some thread pool classes. Methods on the class libraries often enqueue long running taks onto the thread pool from one thread and then the callback methods of that class get invoked on a different thread. As a result, we have a lot of edge case bugs involving incorrect threading assumptions. This results in subtle bugs that go beyond just having critical sections and locks to guard against concurrency issues. What makes these problems even harder is that the attempts to fix are often incorrect. Some mistakes I've observed the team attempting (or within the legacy code itself) includes something like the following: Common mistake #1 - Fixing concurrency issue by just put a lock around the shared data, but forgetting about what happens when methods don't get called in an expected order. Here's a very simple example: void Foo::OnHttpRequestComplete(statuscode status) { m_pBar->DoSomethingImportant(status); } void Foo::Shutdown() { m_pBar->Cleanup(); delete m_pBar; m_pBar=nullptr; } So now we have a bug in which Shutdown could get called while OnHttpNetworkRequestComplete is occuring on. A tester finds the bug, captures the crash dump, and assigns the bug to a developer. He in turn fixes the bug like this. void Foo::OnHttpRequestComplete(statuscode status) { AutoLock lock(m_cs); m_pBar->DoSomethingImportant(status); } void Foo::Shutdown() { AutoLock lock(m_cs); m_pBar->Cleanup(); delete m_pBar; m_pBar=nullptr; } The above fix looks good until you realize there's an even more subtle edge case. What happens if Shutdown gets called before OnHttpRequestComplete gets called back? The real world examples my team has are even more complex, and the edge cases are even harder to spot during the code review process. Common Mistake #2 - fixing deadlock issues by blindly exiting the lock, wait for the other thread to finish, then re-enter the lock - but without handling the case that the object just got updated by the other thread! Common Mistake #3 - Even though the objects are reference counted, the shutdown sequence "releases" it's pointer. But forgets to wait for the thread that is still running to release it's instance. As such, components are shutdown cleanly, then spurious or late callbacks are invoked on an object in an state not expecting any more calls. There are other edge cases, but the bottom line is this: Multithreaded programming is just plain hard, even for smart people. As I catch these mistakes, I spend time discussing the errors with each developer on developing a more appropriate fix. But I suspect they are often confused on how to solve each issue because of the enormous amount of legacy code that the "right" fix will involve touching. We're going to be shipping soon, and I'm sure the patches we're applying will hold for the upcoming release. Afterwards, we're going to have some time to improve the code base and refactor where needed. We won't have time to just re-write everything. And the majority of the code isn't all that bad. But I'm looking to refactor code such that threading issues can be avoided altogether. One approach I am considering is this. For each significant platform feature, have a dedicated single thread where all events and network callbacks get marshalled onto. Similar to COM apartment threading in Windows with use of a message loop. Long blocking operations could still get dispatched to a work pool thread, but the completion callback is invoked on on the component's thread. Components could possibly even share the same thread. Then all the class libraries running inside the thread can be written under the assumption of a single threaded world. Before I go down that path, I am also very interested if there are other standard techniques or design patterns for dealing with multithreaded issues. And I have to emphasize - something beyond a book that describes the basics of mutexes and semaphores. What do you think? I am also interested in any other approaches to take towards a refactoring process. Including any of the following: Literature or papers on design patterns around threads. Something beyond an introduction to mutexes and semaphores. We don't need massive parallelism either, just ways to design an object model so as to handle asynchronous events from other threads correctly. Ways to diagram the threading of various components, so that it will be easy to study and evolve solutions for. (That is, a UML equivalent for discussing threads across objects and classes) Educating your development team on the issues with multithreaded code. What would you do?

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• How can I build pyv8 from source on FreeBSD against the v8 port?

  - by Utkonos

  I am unable to build pyv8 from source on FreeBSD. I have installed the /usr/ports/lang/v8 port, and I'm running into the following error. It seems that pyv8 wants to build v8 itself even though v8 is already built and installed. How can I point pyv8 to the already installed location of v8? # python setup.py build Found Google v8 base on V8_HOME , update it to the latest SVN trunk at running build ==================== INFO: Installing or updating GYP... -------------------- INFO: Check out GYP from SVN ... DEBUG: make dependencies ERROR: Check out GYP from SVN failed: code=2 DEBUG: "Makefile", line 43: Missing dependency operator "Makefile", line 45: Need an operator "Makefile", line 46: Need an operator "Makefile", line 48: Need an operator "Makefile", line 50: Need an operator "Makefile", line 52: Need an operator "Makefile", line 54: Missing dependency operator "Makefile", line 56: Need an operator "Makefile", line 58: Missing dependency operator "Makefile", line 60: Need an operator "Makefile", line 62: Missing dependency operator "Makefile", line 64: Need an operator "Makefile", line 66: Missing dependency operator "Makefile", line 68: Need an operator "Makefile", line 70: Missing dependency operator "Makefile", line 72: Need an operator "Makefile", line 73: Missing dependency operator "Makefile", line 75: Need an operator "Makefile", line 77: Missing dependency operator "Makefile", line 79: Need an operator "Makefile", line 81: Missing dependency operator "Makefile", line 83: Need an operator "Makefile", line 85: Missing dependency operator "Makefile", line 87: Need an operator "Makefile", line 89: Need an operator "Makefile", line 91: Missing dependency operator "Makefile", line 93: Need an operator "Makefile", line 95: Need an operator "Makefile", line 97: Need an operator "Makefile", line 99: Missing dependency operator "Makefile", line 101: Need an operator "Makefile", line 103: Missing dependency operator "Makefile", line 105: Need an operator "Makefile", line 107: Missing dependency operator "Makefile", line 109: Need an operator "Makefile", line 111: Missing dependency operator "Makefile", line 113: Need an operator "Makefile", line 115: Missing dependency operator "Makefile", line 117: Need an operator Error expanding embedded variable. ==================== INFO: Patching the GYP scripts INFO: patch the Google v8 build/standalone.gypi file to enable RTTI and C++ Exceptions ==================== INFO: building Google v8 with GYP for x64 platform with release mode -------------------- INFO: build v8 from SVN ... DEBUG: make verifyheap=off component=shared_library visibility=on gdbjit=off liveobjectlist=off regexp=native disassembler=off objectprint=off debuggersupport=on extrachecks=off snapshot=on werror=on x64.release ERROR: build v8 from SVN failed: code=2 DEBUG: "Makefile", line 43: Missing dependency operator "Makefile", line 45: Need an operator "Makefile", line 46: Need an operator "Makefile", line 48: Need an operator "Makefile", line 50: Need an operator "Makefile", line 52: Need an operator "Makefile", line 54: Missing dependency operator "Makefile", line 56: Need an operator "Makefile", line 58: Missing dependency operator "Makefile", line 60: Need an operator "Makefile", line 62: Missing dependency operator "Makefile", line 64: Need an operator "Makefile", line 66: Missing dependency operator "Makefile", line 68: Need an operator "Makefile", line 70: Missing dependency operator "Makefile", line 72: Need an operator "Makefile", line 73: Missing dependency operator "Makefile", line 75: Need an operator "Makefile", line 77: Missing dependency operator "Makefile", line 79: Need an operator "Makefile", line 81: Missing dependency operator "Makefile", line 83: Need an operator "Makefile", line 85: Missing dependency operator "Makefile", line 87: Need an operator "Makefile", line 89: Need an operator "Makefile", line 91: Missing dependency operator "Makefile", line 93: Need an operator "Makefile", line 95: Need an operator "Makefile", line 97: Need an operator "Makefile", line 99: Missing dependency operator "Makefile", line 101: Need an operator "Makefile", line 103: Missing dependency operator "Makefile", line 105: Need an operator "Makefile", line 107: Missing dependency operator "Makefile", line 109: Need an operator "Makefile", line 111: Missing dependency operator "Makefile", line 113: Need an operator "Makefile", line 115: Missing dependency operator "Makefile", line 117: Need an operator Error expanding embedded variable. The files that are installed by the v8 port are the following (in /usr/local): bin/d8 include/v8.h include/v8-debug.h include/v8-preparser.h include/v8-profiler.h include/v8-testing.h include/v8stdint.h lib/libv8.so lib/libv8.so.1

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• puppet master REST API returns 403 when running under passenger works when master runs from command line

  - by Anadi Misra

  I am using the standard auth.conf provided in puppet install for the puppet master which is running through passenger under Nginx. However for most of the catalog, files and certitifcate request I get a 403 response. ### Authenticated paths - these apply only when the client ### has a valid certificate and is thus authenticated # allow nodes to retrieve their own catalog path ~ ^/catalog/([^/]+)$ method find allow $1 # allow nodes to retrieve their own node definition path ~ ^/node/([^/]+)$ method find allow $1 # allow all nodes to access the certificates services path ~ ^/certificate_revocation_list/ca method find allow * # allow all nodes to store their reports path /report method save allow * # unconditionally allow access to all file services # which means in practice that fileserver.conf will # still be used path /file allow * ### Unauthenticated ACL, for clients for which the current master doesn't ### have a valid certificate; we allow authenticated users, too, because ### there isn't a great harm in letting that request through. # allow access to the master CA path /certificate/ca auth any method find allow * path /certificate/ auth any method find allow * path /certificate_request auth any method find, save allow * path /facts auth any method find, search allow * # this one is not stricly necessary, but it has the merit # of showing the default policy, which is deny everything else path / auth any Puppet master however does not seems to be following this as I get this error on client [amisr1@blramisr195602 ~]$ sudo puppet agent --no-daemonize --verbose --server bangvmpllda02.XXXXX.com [sudo] password for amisr1: Starting Puppet client version 3.0.1 Warning: Unable to fetch my node definition, but the agent run will continue: Warning: Error 403 on SERVER: Forbidden request: XX.XXX.XX.XX(XX.XXX.XX.XX) access to /certificate_revocation_list/ca [find] at :110 Info: Retrieving plugin Error: /File[/var/lib/puppet/lib]: Failed to generate additional resources using 'eval_generate: Error 403 on SERVER: Forbidden request: XX.XXX.XX.XX(XX.XXX.XX.XX) access to /file_metadata/plugins [search] at :110 Error: /File[/var/lib/puppet/lib]: Could not evaluate: Error 403 on SERVER: Forbidden request: XX.XXX.XX.XX(XX.XXX.XX.XX) access to /file_metadata/plugins [find] at :110 Could not retrieve file metadata for puppet://devops.XXXXX.com/plugins: Error 403 on SERVER: Forbidden request: XX.XXX.XX.XX(XX.XXX.XX.XX) access to /file_metadata/plugins [find] at :110 Error: Could not retrieve catalog from remote server: Error 403 on SERVER: Forbidden request: XX.XXX.XX.XX(XX.XXX.XX.XX) access to /catalog/blramisr195602.XXXXX.com [find] at :110 Using cached catalog Error: Could not retrieve catalog; skipping run Error: Could not send report: Error 403 on SERVER: Forbidden request: XX.XXX.XX.XX(XX.XXX.XX.XX) access to /report/blramisr195602.XXXXX.com [save] at :110 and the server logs show XX.XXX.XX.XX - - [10/Dec/2012:14:46:52 +0530] "GET /production/certificate_revocation_list/ca? HTTP/1.1" 403 102 "-" "Ruby" XX.XXX.XX.XX - - [10/Dec/2012:14:46:52 +0530] "GET /production/file_metadatas/plugins?links=manage&recurse=true&&ignore=---+%0A++-+%22.svn%22%0A++-+CVS%0A++-+%22.git%22&checksum_type=md5 HTTP/1.1" 403 95 "-" "Ruby" XX.XXX.XX.XX - - [10/Dec/2012:14:46:52 +0530] "GET /production/file_metadata/plugins? HTTP/1.1" 403 93 "-" "Ruby" XX.XXX.XX.XX - - [10/Dec/2012:14:46:53 +0530] "POST /production/catalog/blramisr195602.XXXXX.com HTTP/1.1" 403 106 "-" "Ruby" XX.XXX.XX.XX - - [10/Dec/2012:14:46:53 +0530] "PUT /production/report/blramisr195602.XXXXX.com HTTP/1.1" 403 105 "-" "Ruby" thefile server conf file is as follows (and goin by what they say on puppet site, It is better to regulate access in auth.conf for reaching file server and then allow file server to server all) [files] path /apps/puppet/files allow * [private] path /apps/puppet/private/%H allow * [modules] allow * I am using server and client version 3 Nginx has been compiled using the following options nginx version: nginx/1.3.9 built by gcc 4.4.6 20120305 (Red Hat 4.4.6-4) (GCC) TLS SNI support enabled configure arguments: --prefix=/apps/nginx --conf-path=/apps/nginx/nginx.conf --pid-path=/apps/nginx/run/nginx.pid --error-log-path=/apps/nginx/logs/error.log --http-log-path=/apps/nginx/logs/access.log --with-http_ssl_module --with-http_gzip_static_module --add-module=/usr/lib/ruby/gems/1.8/gems/passenger-3.0.18/ext/nginx --add-module=/apps/Downloads/nginx/nginx-auth-ldap-master/ and the standard nginx puppet master conf server { ssl on; listen 8140 ssl; server_name _; passenger_enabled on; passenger_set_cgi_param HTTP_X_CLIENT_DN $ssl_client_s_dn; passenger_set_cgi_param HTTP_X_CLIENT_VERIFY $ssl_client_verify; passenger_min_instances 5; access_log logs/puppet_access.log; error_log logs/puppet_error.log; root /apps/nginx/html/rack/public; ssl_certificate /var/lib/puppet/ssl/certs/bangvmpllda02.XXXXXX.com.pem; ssl_certificate_key /var/lib/puppet/ssl/private_keys/bangvmpllda02.XXXXXX.com.pem; ssl_crl /var/lib/puppet/ssl/ca/ca_crl.pem; ssl_client_certificate /var/lib/puppet/ssl/certs/ca.pem; ssl_ciphers SSLv2:-LOW:-EXPORT:RC4+RSA; ssl_prefer_server_ciphers on; ssl_verify_client optional; ssl_verify_depth 1; ssl_session_cache shared:SSL:128m; ssl_session_timeout 5m; } Puppet is picking up the correct settings from the files mentioned because config print command points to /etc/puppet [amisr1@bangvmpllDA02 puppet]$ sudo puppet config print | grep conf async_storeconfigs = false authconfig = /etc/puppet/namespaceauth.conf autosign = /etc/puppet/autosign.conf catalog_cache_terminus = store_configs confdir = /etc/puppet config = /etc/puppet/puppet.conf config_file_name = puppet.conf config_version = "" configprint = all configtimeout = 120 dblocation = /var/lib/puppet/state/clientconfigs.sqlite3 deviceconfig = /etc/puppet/device.conf fileserverconfig = /etc/puppet/fileserver.conf genconfig = false hiera_config = /etc/puppet/hiera.yaml localconfig = /var/lib/puppet/state/localconfig name = config rest_authconfig = /etc/puppet/auth.conf storeconfigs = true storeconfigs_backend = puppetdb tagmap = /etc/puppet/tagmail.conf thin_storeconfigs = false I checked the firewall rules on this VM; 80, 443, 8140, 3000 are allowed. Do I still have to tweak any specifics to auth.conf for getting this to work?

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• Is it possible to repair a Cisco 3500 XL (3548) switch with POST Error messages?

  - by Alex

  I've got an old Cisco 3500 XL, and it seems to have hardware issues. I've loaded the latest IOS and cleared all config. Does anyone have any experience fixing the switch core? I'm a reasonably competent SMD solderer, can I replace/reflow some chips? I've checked the power supply voltages and it's all within tolerance, and no visible signs of any component damage. Some chips are hot to the touch. I understand that these were EOL as of 2007, but should have a lifetime warranty for the electronics. I don't have a Cisco support contract, so I can't file a ticket. What should I do? Console output: switch: dir flash: Directory of flash:/ 2 -rwx 1811584 <date> c3500xl-c3h2s-mz.120-5.WC17.bin 1799680 bytes available (1812992 bytes used) switch: boot Loading "flash:c3500xl-c3h2s-mz.120-5.WC17.bin"...################################################################################################################################################################################### File "flash:c3500xl-c3h2s-mz.120-5.WC17.bin" uncompressed and installed, entry point: 0x3000 executing... Restricted Rights Legend Use, duplication, or disclosure by the Government is subject to restrictions as set forth in subparagraph (c) of the Commercial Computer Software - Restricted Rights clause at FAR sec. 52.227-19 and subparagraph (c) (1) (ii) of the Rights in Technical Data and Computer Software clause at DFARS sec. 252.227-7013. cisco Systems, Inc. 170 West Tasman Drive San Jose, California 95134-1706 Cisco Internetwork Operating System Software IOS (tm) C3500XL Software (C3500XL-C3H2S-M), Version 12.0(5)WC17, RELEASE SOFTWARE (fc1) Copyright (c) 1986-2007 by cisco Systems, Inc. Compiled Tue 13-Feb-07 15:04 by antonino Image text-base: 0x00003000, data-base: 0x00352924 Initializing C3500XL flash... flashfs[1]: 1 files, 1 directories flashfs[1]: 0 orphaned files, 0 orphaned directories flashfs[1]: Total bytes: 3612672 flashfs[1]: Bytes used: 1812992 flashfs[1]: Bytes available: 1799680 flashfs[1]: flashfs fsck took 3 seconds. flashfs[1]: Initialization complete. ...done Initializing C3500XL flash. C3500XL POST: System Board Test: Passed C3500XL POST: Daughter Card Test: Passed C3500XL POST: CPU Buffer Test: Passed C3500XL POST: CPU Notify RAM Test: Passed C3500XL POST: CPU Interface Test: Passed C3500XL POST: Testing Switch Core: Passed Error with Switch Core BIST test Phase 0. Returns: Test Complete Low : 0x0FFFFFFF, Test Complete High : 0xFFFFFFFE Test Phase Low : 0x00000040, Test Phase High : 0x00000000 Test Phase Third : 0x00000000, Test Complete Third : 0x000001F8 C3500XL POST FAILURE: Testing Switch Core: Failed C3500XL POST FAILURE: Testing Buffer Table: Failed C3500XL POST FAILURE: Data Buffer Test: Failed C3500XL POST FAILURE: Configuring Switch Parameters: Failed C3500XL POST FAILURE: Switch Core BIST failed. C3500XL POST FAILURE: Cannot test Modules due to failure of Switch Core POST Del Mar Failure (0th Del Mar): req system failed to init C3500XL POST FAILURE: C3500XL POST FAILURE: ATM: required system failed to init C3500XL POST: Ethernet Controller Test: Passed C3500XL POST FAILURE: MII Test: Failed C3500XL POST FAILURE: Error waiting for Ethernet Controller and SW_PARAMS C3500XL POST FAILURE: Initialization/POST failed C3500XL POST FAILURE: AT: Failing because system POST failed Exception (8192)! Debug Exception (Could be NULL pointer dereference) CPU Register Context: Vector = 0x00002000 PC = 0x000F36F4 MSR = 0x00029200 CR = 0x22000024 LR = 0x000F6964 CTR = 0x001DE46C XER = 0x00000000 R0 = 0x00000000 R1 = 0x004E2580 R2 = 0x00000000 R3 = 0x00000000 R4 = 0x00000001 R5 = 0x00000000 R6 = 0x004E2718 R7 = 0x004E2718 R8 = 0x00000008 R9 = 0x00000000 R10 = 0x0000FFFF R11 = 0x00480000 R12 = 0x42000024 R13 = 0x00000000 R14 = 0x00000000 R15 = 0x00000000 R16 = 0x00000000 R17 = 0x00000000 R18 = 0x00000000 R19 = 0x00000000 R20 = 0x00000000 R21 = 0x00000000 R22 = 0x00000000 R23 = 0x00000000 R24 = 0x00000000 R25 = 0x00000020 R26 = 0x004E2718 R27 = 0x004E2718 R28 = 0x00000020 R29 = 0x00002513 R30 = 0x00000001 R31 = 0x00000000 Stack trace: PC = 0x000F36F4, SP = 0x004E2580 Frame 00: SP = 0x004E25A0 PC = 0x40000016 Frame 01: SP = 0x004E2618 PC = 0x000F6964 Frame 02: SP = 0x004E26A8 PC = 0x000F76DC Frame 03: SP = 0x004E26C8 PC = 0x000E8114 Frame 04: SP = 0x004E26F0 PC = 0x001F5BF8 Frame 05: SP = 0x004E2710 PC = 0x001F5CF4 Frame 06: SP = 0x004E2748 PC = 0x0023F4DC Frame 07: SP = 0x004E2750 PC = 0x0023E650 Frame 08: SP = 0x004E27C8 PC = 0x0023E89C Frame 09: SP = 0x004E27E0 PC = 0x0028AF34 Frame 10: SP = 0x004E27E8 PC = 0x001E38F8 Frame 11: SP = 0x004E2808 PC = 0x001E39A8 Frame 12: SP = 0x004E2820 PC = 0x0014E220 Frame 13: SP = 0x004E28C8 PC = 0x0014E39C Frame 14: SP = 0x00000000 PC = 0x001EB510

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• Single-Signon options for Exchange 2010

  - by freiheit

  We're working on a project to migrate employee email from Unix/open-source (courier IMAP, exim, squirrelmail, etc) to Exchange 2010, and trying to figure out options for single-signon for Outlook Web Access. So far all the options I've found are very ugly and "unsupportable", and may simply not work with Forefront. We already have JA-SIG CAS for token-based single-signon and Shibboleth for SAML. Users are directed to a simple in-house portal (a Perl CGI, really) that they use to sign in to most stuff. We have an HA OpenLDAP cluster that's already synchronized against another AD domain and will be synchronized with the AD domain Exchange will be using. CAS authenticates against LDAP. The portal authenticates against CAS. Shibboleth authenticates with CAS but pulls additional data from LDAP. We're moving in the direction of having web services authenticate against CAS or Shibboleth. (Students are already on SAML/Shibboleth authenticated Google Apps for Education) With Squirrelmail we have a horrible hack linked to from that portal page that authenticates against CAS, gets your original plaintext password (yes, I know, evil), and gives you an HTTP form pre-filled with all the necessary squirrelmail login details with javaScript onLoad stuff to immediately submit the form. Trying to find out exactly what is possible with Exchange/OWA seems to be difficult. "CAS" is both the acronym for our single-signon server and an Exchange component. From what I've been able to tell there's an addon for Exchange that does SAML, but only for federating things like free/busy calendar info, not authenticating users. Plus it costs additional money so there's no way to experiment with it to see if it can be coaxed into doing what we want. Our plans for the Exchange cluster involve Forefront Threat Management Gateway (the new ISA) in the DMZ front-ending the CAS servers. So, the real question: Has anybody managed to make Exchange authenticate with CAS (token-based single-signon) or SAML, or with something I can reasonably likely make authenticate with one of those (such as anything that will accept apache's authentication)? With Forefront? Failing that, anybody have some tips on convincing OWA Forms Based Authentication (FBA) into letting us somehow "pre-login" the user? (log in as them and pass back cookies to the user, or giving the user a pre-filled form that autosubmits like we do with squirrelmail). This is the least-favorite option for a number of reasons, but it would (just barely) satisfy our requirements. From what I hear from the guy implementing Forefront, we may have to set OWA to basic authentication and do forms in Forefront for authentication, so it's possible this isn't even possible. I did find CasOwa, but it only mentions Exchange 2007, looks kinda scary, and as near as I can tell is mostly the same OWA FBA hack I was considering slightly more integrated with the CAS server. It also didn't look like many people had had much success with it. And it may not work with Forefront. There's also "CASifying Outlook Web Access 2", but that one scares me, too, and involves setting up a complex proxy config, which seems more likely to break. And, again, doesn't look like it would work with Forefront. Am I missing something with Exchange SAML (OWA Federated whatchamacallit) where it is possible to configure to do user authentication and not just free/busy access authorization?

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