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• How does real world login process happen in web application in Java?

  - by Nitesh Panchal

  Hello, I am very much confused regarding login process that happen in Java web application. I read many tutorials regarding jdbcRealm and JAAS. But, one thing that i don't understand is that why should i use them ? Can't i simply check directly against my database of users? and once they successfully login to the site, i store some variable in session as a flag. And probably check that session variable on all restricted pages (I mean keep a filter for restricted resources url pattern).If the flag doesn't exist simply redirect the user to login page. Is this approach correct?Does this approch sound correct? If yes, then why did all this JAAS and jdbcRealm came into existence? Secondly, I am trying to completely implement SAS(Software as service) in my web application, meaning everything is done through web services.If i use webservices, is it possible to use jdbcRealm? If not, then is it possible to use JAAS? If yes, then please show me some example which uses mySql as a database and then authenticates and authorizes. I even heard about Spring Security. But, i am confused about that too in the sense that how do i use webservice with Spring Security. Please help me. I am really very confused. I read sun's tutorials but they only keep talking about theories. For programmers to understand a simple concept, they show a 100 page theory first before they finally come to one example.

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• Can anyone give me tips how to solve this using Graphs in C or Java?

  - by peiska

  Can anyone give me tips how to solve this using Graphs in C or Java? I have a rectangular sector, that I have to escape, and I have energy that goes disappear every step that i give in the area. I have to give the only one possible solution, the one that uses the least number of steps. If there are at least two sectors with the same number of steps (X1, Y1) and (X2, Y2) then choose the first if X1 < X2 or if X1 = X2 and Y1 < Y2. the position( 1,1) corresponds to the upper left corner. Examples: This is one sector,and i start with 40 of energy and in the position (3,3) 12 11 12 11 3 12 12 12 11 11 12 2 1 13 11 11 12 2 13 2 14 10 11 13 3 2 1 12 10 11 13 13 11 12 13 12 12 11 13 11 13 12 13 12 12 11 11 11 11 13 13 10 10 13 11 12 the best solution to exit the sector is the position (5, 1) the remain energy is 12 and i need 8 steeps to leave the area. for this sector i start with 8 of energy and in the position (3,4). 4 3 3 2 2 3 2 2 5 2 2 2 3 3 2 1 2 2 3 2 2 4 3 3 2 2 4 1 3 1 4 3 2 3 1 2 2 3 3 0 3 4 And for this one there is no way out, cause it looses all the energy.

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• WPF - Handling events from user control in View Model

  - by Vitaly

  I’m building a WPF application using MVVM pattern (both are new technologies for me). I use user controls for simple bits of reusable functionality that doesn’t contain business logic, and MVVM pattern to build application logic. Suppose a view contains my user control that fires events, and I want to add an event handler to that event. That event handler should be in the view model of the view, because it contains business logic. The question is – view and the view model are connected only by binding; how do I connect an event handler using binding? Is it even possible (I suspect not)? If not – how should I handle events from a control in the view model? Maybe I should use commands or INotifyPropertyChanged?

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• Strategy game programming in Java, how the map and unit classes should work/relate each other.

  - by Gabriel A. Zorrilla

  As a way of learning Java i'm doing a little strategy game. You have a game map and military units. The gamemap and the units are Jpanels which are binded together in another class called GameWindow, which has a JLayeredPane where the gamepap is below the units. Every time i click a unit (and therefore, the JPane) I can get the unit's information. The problem comes when i want to move a unit... each unit is self drawn inside it's Jpanel, how do i represent the change in position over the gamemap? I'm thinking about reloading the whole game window based on a position change of a unit (because the JPAnels that represent the units are created in the GameWindow, not drawn in the gamemap). Another more elegant option, should be repainting the whole map, with the units. But that way the units would lose it's status of objects (no more JPAnels, just being drawn in the gamemap paint() method), and how would i tell if one unit is clicked? I dont know how people with more experience in games handle the class structure in strategy games. I believe i have the right structure (map, game units, each one an object) but I'm having difficulties making it work together. Here is a snapshot of the map with a couple of units:

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• Should java try blocks be scoped as tightly as possible?

  - by isme

  I've been told that there is some overhead in using the Java try-catch mechanism. So, while it is necessary to put methods that throw checked exception within a try block to handle the possible exception, it is good practice performance-wise to limit the size of the try block to contain only those operations that could throw exceptions. I'm not so sure that this is a sensible conclusion. Consider the two implementations below of a function that processes a specified text file. Even if it is true that the first one incurs some unnecessary overhead, I find it much easier to follow. It is less clear where exactly the exceptions come from just from looking at statements, but the comments clearly show which statements are responsible. The second one is much longer and complicated than the first. In particular, the nice line-reading idiom of the first has to be mangled to fit the readLine call into a try block. What is the best practice for handling exceptions in a funcion where multiple exceptions could be thrown in its definition? This one contains all the processing code within the try block: void processFile(File f) { try { // construction of FileReader can throw FileNotFoundException BufferedReader in = new BufferedReader(new FileReader(f)); // call of readLine can throw IOException String line; while ((line = in.readLine()) != null) { process(line); } } catch (FileNotFoundException ex) { handle(ex); } catch (IOException ex) { handle(ex); } } This one contains only the methods that throw exceptions within try blocks: void processFile(File f) { FileReader reader; try { reader = new FileReader(f); } catch (FileNotFoundException ex) { handle(ex); return; } BufferedReader in = new BufferedReader(reader); String line; while (true) { try { line = in.readLine(); } catch (IOException ex) { handle(ex); break; } if (line == null) { break; } process(line); } }

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• Targeting specific material by name in the imported model

  - by Aleksander Lenart

  I'm trying to select a particular material in the imported model (via Collada loader) in Three.js. I know this can be done with the getChildByName method but it just doesn't work for me. I couldn't find any working example with this method included, either. What am I doing wrong here? loader = new THREE.ColladaLoader(); loader.load('myModel.dae', function ( collada ) { model = collada.scene; var myMaterial = model.getChildByName( 'materialName', true ); myMaterial.material = new THREE.MeshBasicMaterial( { wireframe: true } ); });

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• Bind texture with pinned mapped memory in CUDA

  - by sjchoi

  I was trying to bind a host memory that was mapped for zero-copy to a texture, but it looks like it isn't possible. Here is a code sample: float* a; float* d_a; cudaSetDeviceFlags(cudaDeviceMapHost); cudaHostAlloc( (void **)&a, bytes, cudaHostAllocMapped); cudaHostGetDevicePointer((void **)&d_a, (void *)a, 0); texture<float, 2, cudaReadModeElementType> tex; cudaBindTexture2D( 0, &tex, d_a, &channelDesc, width, height, pitch); Is it recommended that you used pinned memory and just copy it over to device memory that is bind to texture?

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• What simple methods are there to wrap a c++ based object model with a COM interface

  - by Rich

  I have a pre-existing c++ object model which represents the business layer tier of an application. I want to be able to expose the object model to applications written in other languages i.e vbscript, VB, javascript etc. I believe the best way of doing this is to wrap the business objects with a COM layer. What fast and effective methods are there for doing this. Any advice, links to practical "How to" documentation would be very much appreciated. Because I'm starting a bounty on this , here's a few extra guidelines for potential bounty hunters :- 1)I've decided on an ATL approach 2)I'm now specifically looking for links to really good "how to and quickly" documentation on wrapping a pre-existing c++ object model to make it useable by a scripting language like javascript 3) Something with small working examples showing me what code needs to be added to what files, e.g what goes into the cpp , idl and hpp/h etc. It' must include an example I can compile test and change to get a better understanding.

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• How to handle model state errors in ajax-invoked controller action that returns a PartialView

  - by Robert Koritnik

  I have a POST controller action that returns a partial view. Everything seems really easy. but. I load it using $.ajax(), setting type as html. But when my model validation fails I thought I should just throw an error with model state errors. But my reply always returns 500 Server error. How can I report back model state errors without returning Json with whatever result. I would still like to return partial view that I can directly append to some HTML element. Edit I would also like to avoid returning error partial view. This would look like a success on the client. Having the client parse the result to see whether it's an actual success is prone to errors. Designers may change the partial view output and this alone would break the functionality. So I want to throw an exception, but with the correct error message returned to the ajax client.

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• Django filter with two constraints on related model

  - by BJ Homer

  I have a django app with models as follows: A Question model An Answer model, with a ForeignKey back to the Question. (A question can have multiple answers.) A Flag model, with a ForeignKey to the Answer. (An answer can be flagged as inappropriate.) All of the above also have a user field, defining the user that created that object. I'm trying to get a list of all Questions with answers from the current user which have been flagged. I tried this: Question.objects.filter(answer__user=user).\ filter(answer__flag__isnull=True).distinct() … but I believe that will return a list of Questions with answers from the current user and with answers which have been flagged, but will not necessarily guarantee that it is the user's answer that has been flagged. Is there an easy way to do this? Basically, I want to make the answer part of the filter refer to the same answer on both of them. Please let me know if something is unclear.

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• How do I post a .wav file from CS5 Flash, AS3 to a Java servlet?

  - by Muostar

  Hi, I am trying to send a byteArray from my .fla to my running tomcat server integrated in Eclipse. From flash I am using the following code: var loader:URLLoader = new URLLoader(); var header:URLRequestHeader = new URLRequestHeader("audio/wav", "application/octet-stream"); var request:URLRequest = new URLRequest("http://localhost:8080/pdp/Server?wav=" + tableID); request.requestHeaders.push(header); request.method = URLRequestMethod.POST; request.data = file;//wav; loader.load(request); And my java servlet looks as follows: try{ int readBytes = -1; int lengthOfBuffer = request.getContentLength(); InputStream input = request.getInputStream(); byte[] buffer = new byte[lengthOfBuffer]; ByteArrayOutputStream output = new ByteArrayOutputStream(lengthOfBuffer); while((readBytes = input.read(buffer, 0, lengthOfBuffer)) != -1) { output.write(buffer, 0, readBytes); } byte[] finalOutput = output.toByteArray(); input.close(); FileOutputStream fos = new FileOutputStream(getServletContext().getRealPath(""+"/temp/"+wav+".wav")); fos.write(finalOutput); fos.close(); When i run the flash .swf file and send the bytearray to the server, I receive following in the server's console window:: (loads of loads of Chinese symbols) May 20, 2010 7:04:57 PM org.apache.tomcat.util.http.Parameters processParameters WARNING: Parameters: Character decoding failed. Parameter '? (loads of loads of Chinese symbols) and then looping this for a long time. It is like I recieve the bytes but not encoding/decoding them correctly. What can I do?

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• ManyToOne annotation fails with Hibernate 4.1: MappingException

  - by barelas

  Using Hibernate 4.1.1.Final. When I try to add @ManyToOne, schema creation fails with: org.hibernate.MappingException: Could not instantiate persister org.hibernate.persister.entity.SingleTableEntityPersister User.java: @Entity public class User { @Id private int id; public int getId() {return id;} public void setId(int id) {this.id = id;} @ManyToOne Department department; public Department getDepartment() {return department;} public void setDepartment(Department department) {this.department = department;} } Department.java @Entity public class Department { @Id private int departmentNumber; public int getDepartmentNumber() {return departmentNumber;} public void setDepartmentNumber(int departmentNumber) {this.departmentNumber = departmentNumber;} } hibernate.properties: hibernate.connection.driver_class=com.mysql.jdbc.Driver hibernate.connection.url=jdbc:mysql://localhost:3306/dbname hibernate.connection.username=user hibernate.connection.password=pass hibernate.connection.pool_size=5 hibernate.dialect=org.hibernate.dialect.MySQL5InnoDBDialect hibernate.hbm2ddl.auto=create init (throwing exception): ServiceRegistry serviceRegistry = new ServiceRegistryBuilder().buildServiceRegistry(); sessionFactory = new MetadataSources( serviceRegistrY.addAnnotatedClass(Department.class).addAnnotatedClass(User.class).buildMetadata().buildSessionFactory(); exception throwed at init: org.hibernate.MappingException: Could not instantiate persister org.hibernate.persister.entity.SingleTableEntityPersister at org.hibernate.persister.internal.PersisterFactoryImpl.create(PersisterFactoryImpl.java:174) at org.hibernate.persister.internal.PersisterFactoryImpl.createEntityPersister(PersisterFactoryImpl.java:148) at org.hibernate.internal.SessionFactoryImpl.<init>(SessionFactoryImpl.java:820) at org.hibernate.metamodel.source.internal.SessionFactoryBuilderImpl.buildSessionFactory(SessionFactoryBuilderImpl.java:65) at org.hibernate.metamodel.source.internal.MetadataImpl.buildSessionFactory(MetadataImpl.java:340) I have tried adding some other annotations, but shouldn't the defaults work and create the tables and foreign key? If I remove the department from User, tables get generated fine. Thanks in advance!

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• I have to select the checkbox two times to check/uncheck in jTable

  - by 117526709403775781607

  I have a jTable code i intend to use, but the problem with it is that when i click on the checkbox once it doesn't select/deselect it, instead i have to click twice. But if i select any other cell in the row except the one containing the checkbox the purpose is solved. HERE IS MY CODE : public class TableSelectionTest extends JFrame implements ListSelectionListener { private final int COLUMN_COUNT = 5; private TblModel model; public TableSelectionTest() { initialize(); setDefaultCloseOperation(EXIT_ON_CLOSE); pack(); } private void initialize() { List data = new ArrayList(); for (int i = 0; i < 10; i++) { Object record[] = new Object[COLUMN_COUNT]; record[0] = Boolean.FALSE; for (int j = 1; j < COLUMN_COUNT; j++) { record[j] = new Integer(j); } data.add(record); } model = new TblModel(data); JTable table = new JTable(model); table.getSelectionModel().setSelectionMode(ListSelectionModel.SINGLE_SELECTION); table.getSelectionModel().addListSelectionListener (this); JScrollPane scroll = new JScrollPane(table); getContentPane().add(scroll, BorderLayout.CENTER); } public static void main(String[] args) { TableSelectionTest f = new TableSelectionTest(); f.show(); } class TblModel extends AbstractTableModel { private List data; public TblModel(List data) { this.data = data; } public int getColumnCount() { return COLUMN_COUNT; } public int getRowCount() { return data == null ? 0 : data.size(); } public void setValueAt(Object value, int rowIndex, int columnIndex) { getRecord(rowIndex)[columnIndex] = value; super.fireTableCellUpdated(rowIndex, columnIndex); } public Object getValueAt(int rowIndex, int columnIndex) { return getRecord(rowIndex)[columnIndex]; } public boolean isCellEditable(int rowIndex, int columnIndex) { if(columnIndex == 0) return true; else return false; } public Class getColumnClass(int columnIndex) { if (data == null || data.size() == 0) { return Object.class; } Object o = getValueAt(0, columnIndex); return o == null ? Object.class : o.getClass(); } private Object[] getRecord(int rowIndex) { return (Object[]) data.get(rowIndex); } } public void valueChanged(ListSelectionEvent e) { if (!e.getValueIsAdjusting()) { ListSelectionModel lsm = (ListSelectionModel) e.getSource(); int index = lsm.getMinSelectionIndex(); if(model.getRecord(index)[0] == Boolean.FALSE) model.setValueAt(Boolean.TRUE, index, 0); else if(model.getRecord(index)[0] == Boolean.TRUE) model.setValueAt(Boolean.FALSE, index, 0); } } } Please reply soon as it is bugging me a lot Thank you in advance :)

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• How does Model binding with a selectlist work?

  - by rsteckly

  Hi, I'm having problems retrieving the values of a selectlist in my form collection. I've tried making a viewmodel with an attribute with the same name as the select list. I'm honestly just realizing I REALLY don't understand how model binding works with selectlists. I've just been assuming that the following conventions apply: Name the select list the same thing as the attribute on the model you want it to bind to. Apart from that, I really don't get it. I've looked at several books on it and they're useless frankly. How does a select list work with a) form collection and b) a particular model?

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• How can I "pack()" a printable Java Swing component?

  - by Jonas

  I have implemented a Java Swing component that implements Printable. If I add the component to a JFrame, and do this.pack(); on the JFrame, it prints perfect. But if I don't add the component to a JFrame, just a blank page is printed. This code gives a great printout: final PrintablePanel p = new PrintablePanel(pageFormat); new JFrame() {{ getContentPane().add(p); this.pack(); }}; job.setPrintable(p, pageFormat); try { job.print(); } catch (PrinterException ex) { System.out.println("Fail"); } But this code gives a blank page: final PrintablePanel p = new PrintablePanel(pageFormat); // new JFrame() {{ getContentPane().add(p); this.pack(); }}; job.setPrintable(p, pageFormat); try { job.print(); } catch (PrinterException ex) { System.out.println("Fail"); } I think that this.pack(); is the big difference. How can I do pack() on my printable component so it prints fine, without adding it to a JFrame? The panel is using several LayoutManagers. I have tried with p.validate(); and p.revalidate(); but it's not working. Any suggestions? Or do I have to add it to a hidden JFrame before I print the component?

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• How to scale JPEG images with a non-standard sampling factor in Java?

  - by HRJ

  I am using Java AWT for scaling a JPEG image, to create thumbnails. The code works fine when the image has a normal sampling factor ( 2x2,1x1,1x1 ) However, an image which has this sampling factor ( 1x1, 1x1, 1x1 ) creates problem when scaled. The colors get corrupted though the features are recognizable. The original and the thumbnail: The code I am using is roughly equivalent to: static BufferedImage awtScaleImage(BufferedImage image, int maxSize, int hint) { // We use AWT Image scaling because it has far superior quality // compared to JAI scaling. It also performs better (speed)! System.out.println("AWT Scaling image to: " + maxSize); int w = image.getWidth(); int h = image.getHeight(); float scaleFactor = 1.0f; if (w > h) scaleFactor = ((float) maxSize / (float) w); else scaleFactor = ((float) maxSize / (float) h); w = (int)(w * scaleFactor); h = (int)(h * scaleFactor); // since this code can run both headless and in a graphics context // we will just create a standard rgb image here and take the // performance hit in a non-compatible image format if any Image i = image.getScaledInstance(w, h, hint); image = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB); Graphics2D g = image.createGraphics(); g.drawImage(i, null, null); g.dispose(); i.flush(); return image; } (Code courtesy of this page ) Is there a better way to do this? Here's a test image with sampling factor of [ 1x1, 1x1, 1x1 ].

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• View artifacts leaking into the model of MVC

  - by Jono

  In an ASP.NET MVC application (which has very little chance of having its view technology ported to something non-HTML, but whose functional requirements evolve weekly,) how much HTML should ideally be allowed to be directly represented in the Model? I might come across as a design bigot for this, but I regard it as bad practice to allow any view constructs to "leak" into the model in an MVC application (and vice versa). For example, a Model that represents an item you're about to purchase should know nothing about the HTML check box that says "add giftwrap/message", nor should it know about any HTML drop down lists for payment card types. Conversely the View shouldn't be doing work like figuring out button text by translating keys into values (by looking in resource files.)

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• Why not put all braces inline in C++/C#/Java/javascript etc.?

  - by DanM

  Of all the conventions out there for positioning braces in C++, C#, Java, etc., I don't think I've ever seen anyone try to propose something like this: public void SomeMethod(int someInput, string someOtherInput) { if (someInput > 5) { var addedNumber = someInput + 5; var subtractedNumber = someInput - 5; } else { var addedNumber = someInput + 10; var subtractedNumber = someInput; } } public void SomeOtherMethod(int someInput, string someOtherInput( { ... } But why not? I'm sure it would take some getting used to, but I personally don't have any difficulty following what's going on here. I believe indentation is the dominant factor in being able to see how code is organized into blocks and sub-blocks. Braces are just visual noise to me. They are these ugly things that take up lines where I don't want them. Maybe I just feel that way because I was weened on basic (and later VB), but I just don't like braces taking up lines. If I want a gap between blocks, I can always add an empty line, but I don't like being forced to have gaps simply because the convention says the closing brace needs to be on its own line. I made this a community wiki because I realize this is not a question with a defined answer. I'm just curious what people think. I know that no one does this currently (at least, not that I've seen), and I know that the auto-formatter in my IDE doesn't support it, but are there are any other solid reasons not to format code this way, assuming you are working with a modern IDE that color codes and auto-indents? Are there scenarios where it will become a readability nightmare? Better yet, are you aware of any research on this?

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• Difficulty porting raw PCM output code from Java to Android AudioTrack API.

  - by IndigoParadox

  I'm attempting to port an application that plays chiptunes (NSF, SPC, etc) music files from Java SE to Android. The Android API seems to lack the javax multimedia classes that this application uses to output raw PCM audio. The closest analog I've found in the API is AudioTrack and so I've been wrestling with that. However, when I try to run one of my sample music files through my port-in-progress, all I get back is static. My suspicion is that it's the AudioTrack I've setup which is at fault. I've tried various different constructors but it all just outputs static in the end. The DataLine setup in the original code is something like: AudioFormat audioFormat = new AudioFormat( AudioFormat.Encoding.PCM_SIGNED, 44100, 16, 2, 4, 44100, true ); DataLine.Info lineInfo = new DataLine.Info( SourceDataLine.class, audioFormat ); DataLine line = (SourceDataLine)AudioSystem.getLine( lineInfo ); The constructor I'm using right now is: AudioTrack = new AudioTrack( AudioManager.STREAM_MUSIC, 44100, AudioFormat.CHANNEL_CONFIGURATION_STEREO, AudioFormat.ENCODING_PCM_16BIT, AudioTrack.getMinBufferSize( 44100, AudioFormat.CHANNEL_CONFIGURATION_STEREO, AudioFormat.ENCODING_PCM_16BIT ), AudioTrack.MODE_STREAM ); I've replaced constants and variables in those so they make sense as concisely as possible, but my basic question is if there are any obvious problems in the assumptions I made when going from one format to the other.

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• How to detect that the internet connection has got disconnected through a java desktop application?

  - by Yatendra Goel

  I am developing a Java Desktop Application that access internet. It is a multi-threaded application, each thread do the same work (means each thread is an instance of same Thread class). Now, as all the threads need internet connection to be active, there should be some mechanism that detects whether an internet connection is active or not. Q1. How to detect whether the internet connection is active or not? Q2. Where to implement this internet-status-check-mechanism code? Should I start a separate thread for checking internet status regularly and notifies all the threads when the status changes from one state to another? Or should I let each thread check for the internet-status itself? Q3. This issue should be a very common issue as every application accessing an internet should deal with this problem. So how other developers usually deal with this problem? Q4. If you could give me a reference to a good demo application that addresses this issue then it would greatly help me.

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• Java/Groovy File IO Replacing an Image File with it's own Contents - Why Does This Work?

  - by jboyd

  I have some JPG files that need to be replaced at runtime with a JFIF standardized version of themselves (we are using a vendor that gives us JPG that do not have proper headers so they don't work in certain applications)... I am able to create a new file from the existing image, then get a buffered image from that file and write the contents right back into the file without having to delete it and it works... imageSrcFolder.eachFileMatch ( ~/.*\.jpg/, { BufferedImage bi = ImageIO.read( it ) ImageIO.write( bi, "jpg", it ) }); The question I have is why? Why doesn't the file end up doubled in size? Why don't I have to delete it first? Why am I able to take a file object to an existing file and then treat it as if it were a brand new one? It seems that what I consider to be a "file" is not what the File object in java actually is, or else this wouldn't work at all. My code does exactly what I want it to do, but I'm not convinced it always will... it just seems way too easy

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• Why doesn't java.util.Set have get(int index)?

  - by Marty Pitt

  I'm sure there's a good reason, but could someone please explain why the java.util.Set interface lacks get(int Index), or any similar get() method? It seems that sets are great for putting things into, but I can't find an elegant way of retrieving a single item from it. If I know I want the first item, I can use set.iterator().next(), but otherwise it seems I have to cast to an Array to retrieve an item at a specific index? What are the appropriate ways of retrieving data from a set? (other than using an iterator) I'm sure the fact that it's excluded from the API means there's a good reason for not doing this -- could someone please enlighten me? EDIT: Some extremely great answers here, and a few saying "more context". The specific scneario was a dbUnit test, where I could reasonalby assert that the returned set from a query had only 1 item, and I was trying to access that item. However, the question is more valid without the scenario, as it remains more focussed : What's the difference between set & list. Thanks to all for the fantastic answers below.

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• Implementing simple business model in Haskell

  - by elmes

  Supose we have a very simple model: Station has at least one Train Train has at least two Stations The model has to allow to check what stations any given train visits and to check what trains visit a particular station. How to model it in Haskell? I am a Haskell newbie, so please correct me: once an object is created, you cannot modify it - you can only make a new object based on that one (~immutability). Am I right? If so, I'll have to create a lot of temporary variables with semi-initialized objects (during deserialization or even in unit tests). Basically what I need is an example of modeling domain classes in Haskell - after reading "Learn you a haskell.." I still have no idea how to use this language.

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• wanting a good memory + disk caching solution

  - by brofield

  I'm currently storing generated HTML pages in a memcached in-memory cache. This works great, however I am wanting to increase the storage capacity of the cache beyond available memory. What I would really like is: memcached semantics (i.e. not reliable, just a cache) memcached api preferred (but not required) large in-memory first level cache (MRU) huge on-disk second level cache (main) evicted from on-disk cache at maximum storage using LRU or LFU proven implementation In searching for a solution I've found the following solutions but they all miss my marks in some way. Does anyone know of either: other options that I haven't considered a way to make memcachedb do evictions Already considered are: memcachedb best fit but doesn't do evictions: explicitly "not a cache" can't see any way to do evictions (either manual or automatic) tugela cache abandoned, no support don't want to recommend it to customers nmdb doesn't use memcache api new and unproven don't want to recommend it to customers

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• How can I support conditional validation of model properties

  - by Jeff

  I currently have a form that I am building that needs to support two different versions. Each version might use a different subset of form fields. I have to do this to support two different clients, but I don't want to have entirely different controller actions for both. So, I am trying to come up with a way to use a strongly typed model with validation attributes but have some of these attributes be conditional. Some approaches I can think of is similar to steve sanderson's partial validation approach. Where I would clear the model errors in a filter OnActionExecuting based on which version of the form was active. The other approach I was thinking of would to break the model up into pieces using something like class FormModel { public Form1 Form1Model {get; set;} public Form2 FormModel {get; set;} } and then we would validate appropriately depending on

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