Search Results

Search found 35513 results on 1421 pages for 'java interfaces'.

Page 734/1421 | < Previous Page | 730 731 732 733 734 735 736 737 738 739 740 741  | Next Page >

  • Better to build or buy a compute grid platform?

    - by James B
    I am looking to do some quite processor-intensive brute force processing for string matching. I have run my prototype in a multi-threaded environment and compared the performance to an implementation using Gridgain with a couple of nodes (also multithreaded). The performance I observed was that my Gridgain implementation performed slower to my multithreaded implementation. It could be the case that there was a flaw in my gridgain implementation, but it was only a prototype, and I thought the results were indicative. So my question is this: What are the advantages of having to learn and then build an implementation for a particular grid platform (hadoop, gridgain, or EC2 if going hosted - other suggestions welcome), when one could fairly easily put together a lightweight compute grid platform with a much shallower learning curve?...i.e. what do we get for free with these cloud/grid platforms that are worth having/tricky to implement? (Please note, I don't have any need for a data grid) Cheers, -James (p.s. Happy to make this community wiki if needbe)

    Read the article

  • How to recursively serialize an object using reflection ?

    - by Tony
    I want to navigate to the N-th level of an object, and serialize it's properties in String format. For Example: class Animal { public String name; public int weight; public Animal friend; public Set<Animal> children = new HashSet<Animal>() ; } should be serialized like this: {name:"Monkey", weight:200, friend:{name:"Monkey Friend",weight:300 ,children:{...if has children}}, children:{name:"MonkeyChild1",weight:100,children:{... recursively nested}} } And you may probably notice that it is similar to serializing an object to json. I know there're many libs can do this, can you give me some instructive ideas on how to write this?

    Read the article

  • Creating GUI for Bantumi game

    - by owca
    I've written backend for simple Bantumi game. Now I'd like to create a simple GUI for it, so that it would look like this : How to start ? What layout should I use, and what type of component each element should be? Classes : Basket Player Game Main Shared

    Read the article

  • Spring transaction demarcation causes new Hibernate session despite use of OSIV

    - by Kelly Ellis
    I'm using Hibernate with OpenSessionInViewInterceptor so that a single Hibernate session will be used for the entire HTTP request (or so I wish). The problem is that Spring-configured transaction boundaries are causing a new session to be created, so I'm running into the following problem (pseudocode): Start in method marked @Transactional(propagation = Propagation.SUPPORTS, readOnly = false) Hibernate session #1 starts Call DAO method to update object foo; foo gets loaded into session cache for session #1 Call another method to update foo.bar, this one is marked @Transactional(propagation = Propagation.REQUIRED, readOnly = false) Transaction demarcation causes suspension of current transaction synchronization, which temporarily unbinds the current Hibernate session Hibernate session #2 starts since there's no currently-existing session Update field bar on foo (loading foo into session cache #2); persist to DB Transaction completes and method returns, session #1 resumes Call yet another method to update another field on foo Load foo from session cache #1, with old, incorrect value of bar Update field foo.baz, persist foo to DB foo.bar's old value overwrites the change we made in the previous step Configuration looks like: <bean name="openSessionInViewInterceptor" class="org.springframework.orm.hibernate3.support.OpenSessionInViewInterceptor" autowire="byName"> <property name="flushModeName"> <value>FLUSH_AUTO</value> </property> </bean> <bean id="txManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> <property name="dataSource" ref="myDataSource" /> </bean> <bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean"> <property name="useTransactionAwareDataSource" value="true" /> <property name="mappingLocations"> <list> <value>/WEB-INF/xml/hibernate/content.hbm.xml</value> </list> </property> <property name="lobHandler"> <ref local="oracleLobHandler" /> </property> <!--property name="entityInterceptor" ref="auditLogInterceptor" /--> <property name="hibernateProperties" ref="HibernateProperties" /> <property name="dataSource" ref="myDataSource" /> </bean> I've done some debugging and figured out exactly where this is happening, here is the stack trace: Daemon Thread [http-8080-1] (Suspended (entry into method doUnbindResource in TransactionSynchronizationManager)) TransactionSynchronizationManager.doUnbindResource(Object) line: 222 TransactionSynchronizationManager.unbindResource(Object) line: 200 SpringSessionSynchronization.suspend() line: 115 DataSourceTransactionManager(AbstractPlatformTransactionManager).doSuspendSynchronization() line: 620 DataSourceTransactionManager(AbstractPlatformTransactionManager).suspend(Object) line: 549 DataSourceTransactionManager(AbstractPlatformTransactionManager).getTransaction(TransactionDefinition) line: 372 TransactionInterceptor(TransactionAspectSupport).createTransactionIfNecessary(TransactionAttribute, String) line: 263 TransactionInterceptor.invoke(MethodInvocation) line: 101 ReflectiveMethodInvocation.proceed() line: 171 JdkDynamicAopProxy.invoke(Object, Method, Object[]) line: 204 $Proxy14.changeVisibility(Long, ContentStatusVO, ContentAuditData) line: not available I can't figure out why transaction boundaries (even "nested" ones - though here we're just moving from SUPPORTS to REQUIRED) would cause the Hibernate session to be suspended, even though OpenSessionInViewInterceptor is in use. When the session is unbound, I see the following in my logs: [2010-02-16 18:20:59,150] DEBUG org.springframework.transaction.support.TransactionSynchronizationManager Removed value [org.springframework.orm.hibernate3.SessionHolder@7def534e] for key [org.hibernate.impl.SessionFactoryImpl@693f23a2] from thread [http-8080-1]

    Read the article

  • Socket server with multiple clients, sending messages to many clients without hurting liveliness

    - by Karl Johanson
    I have a small socket server, and I need to distribute various messages from client-to-client depending on different conditionals. However I think I have a small problem with livelyness in my current code, and is there anything wrong in my approach: public class CuClient extends Thread { Socket socket = null; ObjectOutputStream out; ObjectInputStream in; CuGroup group; public CuClient(Socket s, CuGroup g) { this.socket = s; this.group = g; out = new ObjectOutputStream(this.socket.getOutputStream()); out.flush(); in = new ObjectInputStream(this.socket.getInputStream()); } @Override public void run() { String cmd = ""; try { while (!cmd.equals("client shutdown")) { cmd = (String) in.readObject(); this.group.broadcastToGroup(this, cmd); } out.close(); in.close(); socket.close(); } catch (Exception e) { System.out.println(this.getName()); e.printStackTrace(); } } public void sendToClient(String msg) { try { this.out.writeObject(msg); this.out.flush(); } catch (IOException ex) { } } And my CuGroup: public class CuGroup { private Vector<CuClient> clients = new Vector<CuClient>(); public void addClient(CuClient c) { this.clients.add(c); } void broadcastToGroup(CuClient clientName, String cmd) { Iterator it = this.clients.iterator(); while (it.hasNext()) { CuClient cu = (CuClient)it.next(); cu.sendToClient(cmd); } } } And my main-class: public class SmallServer { public static final Vector<CuClient> clients = new Vector<CuClient>(10); public static boolean serverRunning = true; private ServerSocket serverSocket; private CuGroup group = new CuGroup(); public void body() { try { this.serverSocket = new ServerSocket(1337, 20); System.out.println("Waiting for clients\n"); do { Socket s = this.serverSocket.accept(); CuClient t = new CuClient(s,group); System.out.println("SERVER: " + s.getInetAddress() + " is connected!\n"); t.start(); } while (this.serverRunning); } catch (IOException ex) { ex.printStackTrace(); } } public static void main(String[] args) { System.out.println("Server"); SmallServer server = new SmallServer(); server.body(); } } Consider the example with many more groups, maybe a Collection of groups. If they all synchronize on a single Object, I don't think my server will be very fast. I there a pattern or something that can help my liveliness?

    Read the article

  • Is there a library for editing program flow?

    - by Iulian Serbanoiu
    Hello, I was wondering if there is a library for editing program flow. I refer to conditions if, loops (do, while, for) and other elements that can exist inside a program. What I would like to have is some sort of a CAD application (similar to an UML editor) from where I can take some elements and edit their properties, make connections between them. Do you know similar software that does this, or resembles a little what I'm trying to achieve? Thanks, Iulian PS: It is something that should resemble this image. PS2: I want to write code for doing this, I was wondering if such things exist.

    Read the article

  • Checking if date parsing is correct

    - by Javi
    Hello, I have this code for checking whether the Date is OK or not, but it's not ckecking all the cases. For example when text="03/13/2009" as this date doesn't exist in the format "dd/MM/yyyy" it parses the date as 03/01/2010. Is there any way to change this behaviour and getting an exception when I try to parse a Date which is not correct? What's the best way to do this validation? public static final String DATE_PATTERN = "dd/MM/yyyy"; public static boolean isDate(String text){ SimpleDateFormat formatter = new SimpleDateFormat(DATE_PATTERN); ParsePosition position = new ParsePosition(0); formatter.parse(text, position); if(position.getIndex() != text.length()){ return false; }else{ return true; } } Thanks.

    Read the article

  • How do I determine that an instance of org.apache.poi.hwpf.model.ListData belongs to a numbered lis

    - by leighgordy
    Is there a way to determine if an instance of a org.apache.poi.hwpf.model.ListData belongs to a numbered list or bulleted list? I am using Apache Poi's org.apache.poi.hwpf.HWPFDocument class to read the contents of a word document in order to generate HTML. I can identify the list items in the document by checking to see that the paragraph I am working with is an instance of org.apache.poi.hwpf.model.ListData. I can not find a way to determine if ListData belongs to a bulleted list or a numbered list.

    Read the article

  • Generating equals / hashcode / toString using annotation

    - by Bruno Bieth
    I believe I read somewhere people generating equals / hashcode / toString methods during compile time (using APT) by identifying which fields should be part of the hash / equality test. I couldn't find anything like that on the web (I might have dreamed it ?) ... That could be done like that : public class Person { @Id @GeneratedValue private Integer id; @Identity private String firstName, lastName; @Identity private Date dateOfBirth; //... } For an entity (so we want to exlude some fields, like the id). Or like a scala case class i.e a value object : @ValueObject public class Color { private int red, green, blue; } Not only the file becomes more readable and easier to write, but it also helps ensuring that all the attributes are part of the equals / hashcode (in case you add another attribute later on, without updating the methods accordingly). I heard APT isn't very well supported in IDE but I wouldn't see that as a major issue. After all, tests are mainly run by continuous integration servers. Any idea if this has been done already and if not why ? Thanks

    Read the article

  • Getting message in android app: Binary XML file line #2: You must supply a layout_width attribute.

    - by opike
    I'm trying to use a ListView inside of a RelativeLayout but when I run my app I get a runtimeexception with the message: Binary XML file line #2: You must supply a layout_width attribute. I tried putting layout_width attributes in every conceivable place in the xml resource files but so far no luck. I attempt to populate the listview with this line of code: setListAdapter(new ArrayAdapter(this, R.layout.tablerow3, R.id.label, items)); Here's the tablerow3.xml contents: <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"> android:layout_width="20dp" android:layout_height="5dp" android:id="@+id/tablerow01"> <Label android:id="@+id/label01" android:layout_width="5dp" android:layout_height="5dp" android:textColor="@color/solid_white" android:singleLine="true"/> <Label android:id="@+id/label02" android:layout_width="5dp" android:layout_height="5dp" android:textColor="@color/solid_white" android:singleLine="true"/> </LinearLayout> Here's the xml that contains the RelativeLayout(forex2.xml): <?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent"> <Button android:text="Static Button" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentLeft="true" android:layout_alignParentTop="true" android:id="@+id/button_id"> </Button> <Spinner android:id="@+id/spinner1" android:layout_width="match_parent" android:layout_toRightOf="@id/button_id" android:layout_alignParentTop="true" android:layout_height="wrap_content" android:drawSelectorOnTop="true" /> <ListView android:id="@android:id/list" android:layout_width="5dp" android:layout_height="5dp" android:layout_alignParentBottom="true" /> <!-- android:layout_width="wrap_content" android:layout_height="wrap_content" --> </RelativeLayout>

    Read the article

  • best way to pick a random subset from a collection?

    - by Tom
    I have a set of objects in a Vector from which I'd like to select a random subset (e.g. 100 items coming back; pick 5 randomly). In my first (very hasty) pass I did an extremely simple and perhaps overly clever solution: Vector itemsVector = getItems(); Collections.shuffle(itemsVector); itemsVector.setSize(5); While this has the advantage of being nice and simple, I suspect it's not going to scale very well, i.e. Collections.shuffle() must be O(n) at least. My less clever alternative is Vector itemsVector = getItems(); Random rand = new Random(System.currentTimeMillis()); // would make this static to the class List subsetList = new ArrayList(5); for (int i = 0; i < 5; i++) { // be sure to use Vector.remove() or you may get the same item twice subsetList.add(itemsVector.remove(rand.nextInt(itemsVector.size()))); } Any suggestions on better ways to draw out a random subset from a Collection?

    Read the article

  • Ensure a new session every time the user connects to a Servlet

    - by Daziplqa
    Hi, I've a JSP/Servlet Web App that consist of more than one servlet (and some JSPs) I need to create an new HttpSession whenever the users access servlet A, knowing that, servlet A is the home page (i.e. he access it as the first servlet/page in the application) so far so good, I can write the following code at the start of the servlet A: HttpSession session = request.getSession(false); if (session == null) { logger.debug("starting new session..."); session = request.getSession(); // other staff here } But the problem is, if the user didn't close his browser (even if he closes the tab - in firefox for instance - the session will still be open), so when he try to open my site again, the last session will be re-used (in the rage of session timeout ofcourse), and this I don't need. I need whenever he access Servlet A, he got created a brand new HttpSession. but unfortunately, he may access this servlet twice per session based on some scenario!! Please help.

    Read the article

  • request parameter is taking null value in servlets

    - by Dusk
    Hi, I want to know how can I get the value of the request parameters "j_username" and "j_password"? After successfully login using form based authentication, I want my servlet to get the value of parameters "j_username" and "j_password", but I'm getting null as the value in both parameters. Could anyone please tell me how can I get the actual value of both paramters? Servlets class : package foo; import javax.servlet.http.*; import javax.servlet.*; public class RequestHandler extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) { try { String user = request.getParameter("j_username"); String password = request.getParameter("j_password"); response.getWriter().println(user+" "+password); } catch(Exception e) { e.printStackTrace(); } } } output: null null

    Read the article

  • Placing figure in top-right corner of another

    - by Ivan Dubrov
    I want child figure (org.eclipse.draw2d.Figure) to be relative to the top-right corner of the parent (I want place some small icon, which will be ImageFigure, to be 12 pixels from top and right borders). Is there an existing layout manager that can layout child this way? The org.eclipse.draw2d.XYLayout is not capable of measuring position relative to corner other than top-left. Of course, I can: Write layout manager myself Layout children figure every time bounds are changed for the parent (in parent layout() method). However, I would like to know if some existing layout manager provides that functionality.

    Read the article

  • Android: Can not send http post

    - by jpartogi
    Hi all, I've been banging my head trying to figure out how to send a post method in Android. This is how my code look like: public class HomeActivity extends Activity implements OnClickListener { private TextView textView; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); textView = (TextView) findViewById(R.id.text); Button button = (Button)findViewById(R.id.button); button.setOnClickListener(this); } @Override public void onClick(View view) { HttpPost httpMethod = new HttpPost("http://www.example.com/"); httpMethod.addHeader("Accept", "text/html"); httpMethod.addHeader("Content-Type", "application/xml"); AndroidHttpClient client = AndroidHttpClient.newInstance("Android"); String result = null; try { HttpResponse response = client.execute(httpMethod); textView.setText(response.toString()); HttpEntity entity = response.getEntity(); Log.i(HomeActivity.class.toString(), result); textView.setText("Invoked webservice"); } catch (IOException e) { e.printStackTrace(); Log.e(HomeActivity.class.toString(), e.getMessage()); textView.setText("Something wrong:" + e.getMessage()); } } } What am I doing wrong here? Is there anything that I may need to configure from the Android emulator to get this working? Thank you for your help.

    Read the article

< Previous Page | 730 731 732 733 734 735 736 737 738 739 740 741  | Next Page >