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  • Can't run my servlet from tomcat server even though the classes are in package

    - by Mido
    Hi there, i am trying to get my servlet to run, i have been searching for 2 days and trying every possible solution and no luck. The servet class is in the appropriate folder (i.e under the package name). I also added the jar files needed in my servlet into lib folder. the web.xml file maps the url and defines the servlet. So i did everything in the documentation and wt people said in here and still getting this error : type Exception report message description The server encountered an internal error () that prevented it from fulfilling this request. exception javax.servlet.ServletException: Error instantiating servlet class assign1a.RPCServlet org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:108) org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:558) org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:379) org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:282) org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:357) org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:1687) java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) java.lang.Thread.run(Thread.java:619) root cause java.lang.NoClassDefFoundError: assign1a/RPCServlet (wrong name: server/RPCServlet) java.lang.ClassLoader.defineClass1(Native Method) java.lang.ClassLoader.defineClassCond(ClassLoader.java:632) java.lang.ClassLoader.defineClass(ClassLoader.java:616) java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141) org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappClassLoader.java:2820) org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:1143) org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1638) org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1516) org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:108) org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:558) org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:379) org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:282) org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:357) org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:1687) java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) java.lang.Thread.run(Thread.java:619) note The full stack trace of the root cause is available in the Apache Tomcat/7.0.5 logs. Also here is my servlet code : package assign1a; import java.io.IOException; import java.util.logging.Level; import java.util.logging.Logger; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import lib.jsonrpc.RPCService; public class RPCServlet extends HttpServlet { /** * */ private static final long serialVersionUID = -5274024331393844879L; private static final Logger log = Logger.getLogger(RPCServlet.class.getName()); protected RPCService service = new ServiceImpl(); public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException { response.setContentType("text/html"); response.getWriter().write("rpc service " + service.getServiceName() + " is running..."); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException { try { service.dispatch(request, response); } catch (Throwable t) { log.log(Level.WARNING, t.getMessage(), t); } } } Please help me :) Thanks. EDIT: here are the contents of my web.xml file <web-app xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" version="3.0" metadata-complete="true"> <servlet> <servlet-name>jsonrpc</servlet-name> <servlet-class>assign1a.RPCServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>jsonrpc</servlet-name> <url-pattern>/rpc</url-pattern> </servlet-mapping> </web-app>

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  • Unresolved compilation problems -- can't use .jar files that I have created

    - by Mike
    I created a few .jar files and am trying to access them in another application - I have tried to use both Eclipse and IntelliJ and experience the same issue: java.lang.Error: Unresolved compilation problems: The import com.XXXX.XXXXXXXXX.project2 cannot be resolved The import com.XXXX.XXXXXXXXX.project2 cannot be resolved BeanFactory cannot be resolved to a type Author cannot be resolved to a type AuthorFactoryImpl cannot be resolved to a type Author cannot be resolved to a type Author cannot be resolved to a type I have been using Maven during this process and the jars compile fine. I have included them on the file path using both the Maven .pom file and directly assigning them. I also have unassigned the direct file path and left the reference in Maven and vise versa -- no difference. See below .jar file class info: file structure: Author.java BeanWithIdentityInterface Books Subject ie: Interface: package com.XXXX.training; /** * Created with IntelliJ IDEA. * User: kBPersonal * Date: 11/5/12 * Time: 3:16 PM * */ public interface BeanWithIdentityInterface <I> { I getId(); } Author.java: package com.XXXX.training; /** * Created with IntelliJ IDEA. * User: kBPersonal * Date: 10/25/12 * Time: 12:03 PM */ public class Author implements BeanWithIdentityInterface <Integer>{ private Integer id = null; private String name = null; private String picture = null; private String bio = null; public Author(Integer id, String bio, String name, String picture) { this.id = id; this.bio = bio; this.name = name; this.picture = picture; } public Author (){} @Override public Integer getId() { return id; } public void setId(Integer id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getPicture() { return picture; } public void setPicture(String picture) { this.picture = picture; } public String getBio() { return bio; } public void setBio(String bio) { this.bio = bio; } @Override public String toString() { return "\n\tAuthor Id: "+this.getId() + " | Bio:"+ this.getBio()+ " | Name:"+ this.getName()+ " | Picture: "+ this.getPicture(); } } implementing Servlet: package com.acentia.training.project3.controller; import com.acentia.training.*; import com.acentia.training.project2.AuthorFactoryImpl; import com.acentia.training.project2.BeanFactory; import javax.servlet.ServletException; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException; import java.io.PrintWriter; /** * Created with IntelliJ IDEA. * User: kBPersonal * Date: 11/11/12 * Time: 6:34 PM * */ public class ListAuthorServlet extends AbstractBaseServlet { private static final long serialVersionUID = -6934109551750492182L; public void doProcess(final HttpServletRequest request, final HttpServletResponse response) throws IOException { final BeanFactory<Author, Integer> authorFactory = new AuthorFactoryImpl(); Author author = null; if (authorFactory != null) { author = (Author) authorFactory.getMember(5); } I can't pull the Author class. Any help would be greatly appreciated.

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  • How to load models in the extended MY_Router class in codeigniter

    - by askkirati
    I am not able to load models to the extended My_Router class in codeigniter. Below is my code: class MY_Router extends CI_Router { function MY_Router() { parent::CI_Router(); } function _validate_request($segments) { // Does the requested controller exist in the root folder? if (file_exists(APPPATH.'controllers/'.$segments[0].EXT)) { return $segments; } // Is the controller in a sub-folder? if (is_dir(APPPATH.'controllers/'.$segments[0])) { // Set the directory and remove it from the segment array $this->set_directory($segments[0]); $segments = array_slice($segments, 1); if (count($segments) > 0) { // Does the requested controller exist in the sub-folder? if ( ! file_exists(APPPATH.'controllers/'.$this->fetch_directory().$segments[0].EXT)) { show_404($this->fetch_directory().$segments[0]); } } else { $this->set_class($this->default_controller); $this->set_method('index'); // Does the default controller exist in the sub-folder? if ( ! file_exists(APPPATH.'controllers/'.$this->fetch_directory().$this->default_controller.EXT)) { $this->directory = ''; return array(); } } return $segments; } // Let's check if there are category segments $category_routes = $this->category_routing($segments); if($category_routes !== FALSE) { return $category_routes; } $user_routes = $this->user_routing($segments); if($user_routes != FALSE) { return $user_routes; } show_404($segments[0]); } function category_routing($segments) { $this->load->model('category_model'); if($this->category_model->category_exist($segments[0])) { //if only category if(count($segments)==1) { return array('category', 'category_browse', $segments[0]); } //category pagination if(count($segments)==2 and is_numeric($segments[1])) { return array('category','category_browse', $segments[0], $segments[1]); } //category upcoming if(count($segments)==2 and $segments[1] == 'upcoming') { return array('category','upcoming', $segments[0]); } //category upcoming pagination if(count($segments)==3 and $segments[1] == 'upcoming' and is_numeric($segments[3])) { return array('category','upcoming', $segments[0], $segments[3]); } //category top if(count($segments)==3 and $segments[1] == 'top') { return array('category','top', $segments[0], $segments[2]); } //category top pagination if(count($segments)==4 and $segments[1] == 'top' and is_numeric($segments[3])) { return array('category','top', $segments[0], $segments[3]); } } return FALSE; } function user_routing($segments) { $this->load->model('dx_auth/users', 'user_model'); if($this->user_model->check_username($segments[0])) { //only profile if(count($segments)==1) { return array('user','profile',$segments[0]); } //all friends if(count($segments)==2 and $segment[1]=='allfriends') { return array('user','allfriends',$segments[0]); } //all subscribers if(count($segments)==2 and $segment[1]=='allsubscribers') { return array('user','allsubscribers',$segments[0]); } //all subscription if(count($segments)==2 and $segment[1]=='allsubscriptions') { return array('user','allsubscriptions',$segments[0]); } } return FALSE; } } I have tried loading the models by using get_instance function provided by codeigniter but seems like it doesnot work. All i need is load the models in extended system library.

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  • Provider<HttpSession> not getting injected

    - by user1033715
    I am using gwt dispatch to communicate and get data from server to client. In order to get user specific data I want to store the user object in httpsession and access application specific data from servlet context but when I inject Provider<HttpSession> when the handler execute is called but the dispatchservlet the provider is null i.e it does not get injected. following is the code from my action handler @Inject Provider<HttpSession> provider; public ReadEntityHandler() { } @Override public EntityResult execute(ReadEntityAction arg0, ExecutionContext arg1) throws DispatchException { HttpSession session = null; if (provider == null) System.out.println("httpSession is null.."); else { session = provider.get(); System.out.println("httpSession not null.."); } System.out.println("reached execution"); return null; } and my Dispatch servlet @Singleton public class ActionDispatchServlet extends RemoteServiceServlet implements StandardDispatchService { private Dispatch dispatch; public ActionDispatchServlet() { InstanceActionHandlerRegistry registry = new DefaultActionHandlerRegistry(); registry.addHandler(new ReadEntityHandler()); dispatch = new SimpleDispatch(registry); } @Override public Result execute(Action<?> action) throws DispatchException { try { return dispatch.execute(action); } catch (RuntimeException e) { log("Exception while executing " + action.getClass().getName() + ": " + e.getMessage(), e); throw e; } } } when I try to inject the ReadEntityHandler it throws the following exception [WARN] failed guiceFilter com.google.inject.ProvisionException: Guice provision errors: 1) Error injecting constructor, java.lang.NullPointerException at com.ensarm.wikirealty.server.service.ActionDispatchServlet.<init>(ActionDispatchServlet.java:22) at com.ensarm.wikirealty.server.service.ActionDispatchServlet.class(ActionDispatchServlet.java:22) while locating com.ensarm.wikirealty.server.service.ActionDispatchServlet 1 error at com.google.inject.internal.InjectorImpl$4.get(InjectorImpl.java:834) at com.google.inject.internal.InjectorImpl.getInstance(InjectorImpl.java:856) at com.google.inject.servlet.ServletDefinition.init(ServletDefinition.java:74) at com.google.inject.servlet.ManagedServletPipeline.init(ManagedServletPipeline.java:84) at com.google.inject.servlet.ManagedFilterPipeline.initPipeline(ManagedFilterPipeline.java:106) at com.google.inject.servlet.GuiceFilter.init(GuiceFilter.java:168) at org.mortbay.jetty.servlet.FilterHolder.doStart(FilterHolder.java:97) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39) at org.mortbay.jetty.servlet.ServletHandler.initialize(ServletHandler.java:593) at org.mortbay.jetty.servlet.Context.startContext(Context.java:140) at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1220) at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:513) at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:448) at com.google.gwt.dev.shell.jetty.JettyLauncher$WebAppContextWithReload.doStart(JettyLauncher.java:468) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39) at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130) at org.mortbay.jetty.handler.RequestLogHandler.doStart(RequestLogHandler.java:115) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39) at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130) at org.mortbay.jetty.Server.doStart(Server.java:222) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39) at com.google.gwt.dev.shell.jetty.JettyLauncher.start(JettyLauncher.java:672) at com.google.gwt.dev.DevMode.doStartUpServer(DevMode.java:509) at com.google.gwt.dev.DevModeBase.startUp(DevModeBase.java:1068) at com.google.gwt.dev.DevModeBase.run(DevModeBase.java:811) at com.google.gwt.dev.DevMode.main(DevMode.java:311) Caused by: java.lang.NullPointerException at net.customware.gwt.dispatch.server.DefaultActionHandlerRegistry.addHandler(DefaultActionHandlerRegistry.java:21) at com.ensarm.wikirealty.server.service.ActionDispatchServlet.<init>(ActionDispatchServlet.java:24) at com.ensarm.wikirealty.server.service.ActionDispatchServlet$$FastClassByGuice$$e0a28a5d.newInstance(<generated>) at com.google.inject.internal.cglib.reflect.FastConstructor.newInstance(FastConstructor.java:40) at com.google.inject.internal.DefaultConstructionProxyFactory$1.newInstance(DefaultConstructionProxyFactory.java:58) at com.google.inject.internal.ConstructorInjector.construct(ConstructorInjector.java:84) at com.google.inject.internal.ConstructorBindingImpl$Factory.get(ConstructorBindingImpl.java:200) at com.google.inject.internal.ProviderToInternalFactoryAdapter$1.call(ProviderToInternalFactoryAdapter.java:43) at com.google.inject.internal.InjectorImpl.callInContext(InjectorImpl.java:878) at com.google.inject.internal.ProviderToInternalFactoryAdapter.get(ProviderToInternalFactoryAdapter.java:40) at com.google.inject.Scopes$1$1.get(Scopes.java:64) at com.google.inject.internal.InternalFactoryToProviderAdapter.get(InternalFactoryToProviderAdapter.java:40) at com.google.inject.internal.InjectorImpl$4$1.call(InjectorImpl.java:825) at com.google.inject.internal.InjectorImpl.callInContext(InjectorImpl.java:871) at com.google.inject.internal.InjectorImpl$4.get(InjectorImpl.java:821) ... 25 more

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  • Placing component on Glass Pane

    - by Chris Lieb
    I have a subclass of JLabel that forms a component of my GUI. I have implemented the ability to drag and drop the component from one container to another, but without any visual effects. I want to have this JLabel follow the cursor during the drag of the item from one container to another. I figured that I could just create a glass pane and draw it on there. However, even after I add the component to the glass pane, set the component visible, and set the glass pane visible, and set the glass pane as opaque, I still so not see the component. I know the component works because I can add it to the content pane and have it show up. How do I add a component to the glass pane? package wpics509s10t7.view; import javax.swing.*; import wpics509s10t7.model.Tile; import java.awt.*; import java.awt.dnd.DragSource; import java.awt.event.AWTEventListener; import java.awt.event.MouseEvent; /** * GlassPane tutorial * "A well-behaved GlassPane" * http://weblogs.java.net/blog/alexfromsun/ * <p/> * This is the final version of the GlassPane * it is transparent for MouseEvents, * and respects underneath component's cursors by default, * it is also friedly for other users, * if someone adds a mouseListener to this GlassPane * or set a new cursor it will respect them * * @author Alexander Potochkin */ public class GlassPane extends JPanel implements AWTEventListener { private static final long serialVersionUID = 1L; private final JFrame frame; private TileView tv; // subclass of JLabel private Point point; private WordStealApp wsa; public GlassPane(JFrame frame, WordStealApp wsa) { super(null); this.wsa = wsa; this.frame = frame; setOpaque(true); setLayout(null); setVisible(true); composite = AlphaComposite.getInstance(AlphaComposite.SRC_OVER, 0.5f); } public void beginDrag(Tile t, Point p) { this.tv = new TileView(t, null, this.wsa, true); this.add(this.tv); System.out.println("Starting point: x=" + p.getX() + ",y=" + p.getY()); this.tv.setLocation((int)p.getX(), (int)p.getY()); this.tv.setVisible(true); } public void endDrag(Point p) { System.out.println("Ending point: x=" + p.getX() + ",y=" + p.getY()); this.remove(this.tv); this.tv.setVisible(false); this.tv = null; } public void eventDispatched(AWTEvent event) { if (event instanceof MouseEvent) { MouseEvent me = (MouseEvent) event; if (!SwingUtilities.isDescendingFrom(me.getComponent(), frame)) { return; } if (me.getID() == MouseEvent.MOUSE_EXITED && me.getComponent() == frame) { if (tv != null) { tv.setVisible(false); } point = null; } else { MouseEvent converted = SwingUtilities.convertMouseEvent(me.getComponent(), me, frame.getGlassPane()); point = converted.getPoint(); } repaint(); } } /** * If someone adds a mouseListener to the GlassPane or set a new cursor * we expect that he knows what he is doing * and return the super.contains(x, y) * otherwise we return false to respect the cursors * for the underneath components */ @Override public boolean contains(int x, int y) { if (getMouseListeners().length == 0 && getMouseMotionListeners().length == 0 && getMouseWheelListeners().length == 0 && getCursor() == Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR)) { return false; } return super.contains(x, y); } }

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  • Progressbar blocks notiyfyDatasetChanged() method in Android

    - by pathfinder
    I'm trying to display a ProgressBar while a listview is being populated. This is my XML <FrameLayout android:layout_width="fill_parent" android:layout_height="wrap_content" > <ListView android:id="@android:id/list" android:layout_width="fill_parent" android:layout_height="fill_parent" android:divider="@null" android:dividerHeight="0dp" android:fadingEdge="none" > </ListView> <ProgressBar android:id="@+id/doProgress" android:layout_width="60dp" android:layout_height="60dp" android:layout_gravity="center" /> </FrameLayout> ProgressBar's visibiliy has been changed in the onPostExecuteMethod when the whole listview is loaded. AsyncTask Code: public class WhatToDoLoader extends AsyncTask<String, String, String> { ProgressDialog progress = new ProgressDialog(WhatToDo.this); String url = "http://wearedesigners.net/clients/clients12/tourism/fetchWhatToDoList.php"; final String TAG_MAIN = "item"; final String TAG_ID = "itemId"; final String TAG_NAME = "itemName"; final String TAG_DETAIL = "itemDetailText"; final String TAG_ITEM_IMAGE = "itemImages"; final String TAG_MAP = "itemMapData"; final String TAG_MAP_IMAGE = "mapImage"; @Override protected void onProgressUpdate(String... values) { // TODO Auto-generated method stub super.onProgressUpdate(values); adapter.notifyDataSetChanged(); } @Override protected void onPreExecute() { // TODO Auto-generated method stub super.onPreExecute(); /* * progress.setMessage("Loading What To Do List"); progress.show(); */ } @Override protected String doInBackground(String... params) { XMLParser parser = new XMLParser(); String xml = parser.getXmlFromUrl(url); // getting XML Document doc = parser.getDomElement(xml); // getting DOM element NodeList nl = doc.getElementsByTagName(TAG_MAIN); // TODO Auto-generated method stub for (int i = 0; i < nl.getLength(); i++) { // creating new HashMap HashMap<String, String> map = new HashMap<String, String>(); Element e = (Element) nl.item(i); // adding each child node to HashMap key => value map.put(TAG_ID, parser.getValue(e, TAG_ID)); map.put(TAG_NAME, parser.getValue(e, TAG_NAME)); map.put(TAG_DETAIL, parser.getValue(e, TAG_DETAIL)); map.put(TAG_MAP, parser.getValue(e, TAG_MAP)); map.put(TAG_MAP_IMAGE, parser.getValue(e, TAG_MAP_IMAGE)); map.put(TAG_ITEM_IMAGE, parser.getValue(e, TAG_ITEM_IMAGE)); System.out.println("Test : " + parser.getValue(e, TAG_ID)); // adding HashList to ArrayList whatToDoInfo.add(map); publishProgress(""); } return null; } @Override protected void onPostExecute(String result) { // TODO Auto-generated method stub super.onPostExecute(result); ProgressBar pb = (ProgressBar) findViewById(R.id.doProgress); pb.setVisibility(pb.INVISIBLE); } } When i run the code it throws the following exception. *java.lang.IllegalStateException: The content of the adapter has changed but ListView did not receive a notification. Make sure the content of your adapter is not modified from a background thread, but only from the UI thread.* But the same code works fine when the progressbar feature is omitted. I can't find where i'm going wrong. can someone please help me ? Thank you in advance.

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  • Managing highly repetitive code and documentation in Java

    - by polygenelubricants
    Highly repetitive code is generally a bad thing, and there are design patterns that can help minimize this. However, sometimes it's simply inevitable due to the constraints of the language itself. Take the following example from java.util.Arrays: /** * Assigns the specified long value to each element of the specified * range of the specified array of longs. The range to be filled * extends from index <tt>fromIndex</tt>, inclusive, to index * <tt>toIndex</tt>, exclusive. (If <tt>fromIndex==toIndex</tt>, the * range to be filled is empty.) * * @param a the array to be filled * @param fromIndex the index of the first element (inclusive) to be * filled with the specified value * @param toIndex the index of the last element (exclusive) to be * filled with the specified value * @param val the value to be stored in all elements of the array * @throws IllegalArgumentException if <tt>fromIndex &gt; toIndex</tt> * @throws ArrayIndexOutOfBoundsException if <tt>fromIndex &lt; 0</tt> or * <tt>toIndex &gt; a.length</tt> */ public static void fill(long[] a, int fromIndex, int toIndex, long val) { rangeCheck(a.length, fromIndex, toIndex); for (int i=fromIndex; i<toIndex; i++) a[i] = val; } The above snippet appears in the source code 8 times, with very little variation in the documentation/method signature but exactly the same method body, one for each of the root array types int[], short[], char[], byte[], boolean[], double[], float[], and Object[]. I believe that unless one resorts to reflection (which is an entirely different subject in itself), this repetition is inevitable. I understand that as a utility class, such high concentration of repetitive Java code is highly atypical, but even with the best practice, repetition does happen! Refactoring doesn't always work because it's not always possible (the obvious case is when the repetition is in the documentation). Obviously maintaining this source code is a nightmare. A slight typo in the documentation, or a minor bug in the implementation, is multiplied by however many repetitions was made. In fact, the best example happens to involve this exact class: Google Research Blog - Extra, Extra - Read All About It: Nearly All Binary Searches and Mergesorts are Broken (by Joshua Bloch, Software Engineer) The bug is a surprisingly subtle one, occurring in what many thought to be just a simple and straightforward algorithm. // int mid =(low + high) / 2; // the bug int mid = (low + high) >>> 1; // the fix The above line appears 11 times in the source code! So my questions are: How are these kinds of repetitive Java code/documentation handled in practice? How are they developed, maintained, and tested? Do you start with "the original", and make it as mature as possible, and then copy and paste as necessary and hope you didn't make a mistake? And if you did make a mistake in the original, then just fix it everywhere, unless you're comfortable with deleting the copies and repeating the whole replication process? And you apply this same process for the testing code as well? Would Java benefit from some sort of limited-use source code preprocessing for this kind of thing? Perhaps Sun has their own preprocessor to help write, maintain, document and test these kind of repetitive library code? A comment requested another example, so I pulled this one from Google Collections: com.google.common.base.Predicates lines 276-310 (AndPredicate) vs lines 312-346 (OrPredicate). The source for these two classes are identical, except for: AndPredicate vs OrPredicate (each appears 5 times in its class) "And(" vs Or(" (in the respective toString() methods) #and vs #or (in the @see Javadoc comments) true vs false (in apply; ! can be rewritten out of the expression) -1 /* all bits on */ vs 0 /* all bits off */ in hashCode() &= vs |= in hashCode()

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  • Swing button repaint issue

    - by KáGé
    Hello, I'm new to java and I have to get a school project done by Sunday and got a problem. Here's the code: private abstract class GamePanel { JPanel panel = null; } private class PutPanel extends GamePanel { JButton putShip1 = new JButton(""); JButton putShip2 = new JButton(""); JButton putShip3 = new JButton(""); JButton putShip4 = new JButton(""); ShipDirection ship1Direction = ShipDirection.NORTH; ShipDirection ship2Direction = ShipDirection.NORTH; ShipDirection ship3Direction = ShipDirection.NORTH; ShipDirection ship4Direction = ShipDirection.NORTH; JButton startButton = new JButton("Start game"); public PutPanel(){ this.panel = new JPanel(); panel.setSize(200, Torpedo.session.map.size*Field.buttonSize+300); panel.setBackground(Color.blue); putShip1.setSize(90, 90); putShip1.setLocation(55, 5); putShip1.setIcon(createImageIcon(Torpedo.session.map.shipPath+"/ship1/full_north.png", null)); putShip2.setSize(90, 90); putShip2.setLocation(55, 105); putShip2.setIcon(createImageIcon(Torpedo.session.map.shipPath+"/ship2/full_north.png", null)); putShip3.setSize(90, 90); putShip3.setLocation(55, 205); putShip3.setIcon(createImageIcon(Torpedo.session.map.shipPath+"/ship3/full_north.png", null)); putShip4.setSize(90, 90); putShip4.setLocation(55, 305); putShip4.setIcon(createImageIcon(Torpedo.session.map.shipPath+"/ship4/full_north.png", null)); startButton.setSize(150, 30); startButton.setLocation(20, Torpedo.session.map.size*Field.buttonSize+205); panel.add(putShip1); panel.add(putShip2); panel.add(putShip3); panel.add(putShip4); panel.add(startButton); startButton.addActionListener(startButton()); startButton.addActionListener(putShip1()); startButton.addActionListener(putShip2()); startButton.addActionListener(putShip3()); startButton.addActionListener(putShip4()); panel.setLayout(null); panel.setVisible(true); } private ActionListener startButton(){ return new ActionListener(){ public void actionPerformed(ActionEvent e) { putPanel.panel.setVisible(false); actionPanel.panel.setVisible(true); } }; } private ActionListener putShip1(){ return new ActionListener(){ public void actionPerformed(ActionEvent e) { selectedShip = 1; putShip1.setBackground(Color.red); putShip2.setBackground(null); putShip3.setBackground(null); putShip4.setBackground(null); switch(ship1Direction){ case NORTH: ship1Direction = ShipDirection.EAST; putShip1.setIcon(createImageIcon(Torpedo.session.map.shipPath+"/ship1/full_east.png", null)); break; case EAST: ship1Direction = ShipDirection.SOUTH; putShip1.setIcon(createImageIcon(Torpedo.session.map.shipPath+"/ship1/full_south.png", null)); break; case SOUTH: ship1Direction = ShipDirection.WEST; putShip1.setIcon(createImageIcon(Torpedo.session.map.shipPath+"/ship1/full_west.png", null)); break; case WEST: ship1Direction = ShipDirection.NORTH; putShip1.setIcon(createImageIcon(Torpedo.session.map.shipPath+"/ship1/full_north.png", null)); break; } putShip1.repaint(); putShip2.repaint(); putShip3.repaint(); putShip4.repaint(); panel.repaint(); JOptionPane.showMessageDialog(new JFrame(), "Repaint finished", "Repaint status info", JOptionPane.INFORMATION_MESSAGE); //this here hangs the program when the method is finally called } }; When one of the putShip* buttons is clicked, it should rotate its own icon right 90° (means changing it to the next image), but it does nothing until the startButton is clicked, which changes the panel to an other one. (Only the first button's actionListener is here, the others' are practically the same). The panel is in a JFrame with two other panels that yet do nothing. How could I make it work properly? Thank you.

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  • Android: preferences not being stored automatically

    - by Vitaly
    I'm trying to use preference screen. I'm following all steps from online tutorial (once I couldn't get it working, I found other tutorials, and steps seem to be fine). I get to preferences screen, edit values, return to calling activity (via hardware return button). In DDMS perspective FileExplorer shows package_name_preferences.xml file with preferences that should be stored. It contains: <?xml version='1.0' encoding='utf-8' standalone='yes' ?> <map> <string name="false">kg</string> </map> while I expect (data line only shown). <string name="weight">kg</string> Also, if I go change only 1 preference, the same value changes, not a new row is created. I'm just tempted to write my own preference classes that would store data in files or DB, but I know that preferences should work, it just doesn't save properly my stuff. Edit Tutorials used: Main Tutorial - Was using this as a base, simplified, as I needed only 3 listPreferences so far. Another One - Used this one back when first installed android, so referred to this one for its section on preferences Code: (Screen loads, so I'm not showing Manifest) public class MyPrefs extends PreferenceActivity { @Override public void onCreate(Bundle bundle) { super.onCreate(bundle); addPreferencesFromResource(R.xml.my_prefs); } } my_prefs.xml <PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android"> <PreferenceCategory android:title="Value Settings"> <ListPreference android:title="Distance" android:summary="Metric (Kilometer) vs Imperial (Imperial)" android:defaultValue="km" android:key="@+id/distanceMesurement" android:entries="@array/distance" android:entryValues="@array/distance_values"/> <ListPreference android:title="Weight" android:summary="Metric (Kilogram) vs Imperial (Pound)" android:defaultValue="kg" android:key="@+id/weightMesurement" android:entries="@array/weight" android:entryValues="@array/weight_values"/> </PreferenceCategory> </PreferenceScreen> calling MyPrefs from MainScreen Intent i = new Intent(MainScreen.this, MyPrefs.class); startActivity(i); arrays.xml <resources> <string-array name="weight"> <item name="kg">Kilogram (kg)</item> <item name="lb">Pound (lb)</item> </string-array> <string-array name="weight_values"> <item name="kg">kg</item> <item name="lb">lb</item> </string-array> <string-array name="distance"> <item name="km">Kilometer (km)</item> <item name="mi">Mile (mi)</item> </string-array> <string-array name="distance_values"> <item name="km">km</item> <item name="mi">mi</item> </string-array> </resources>

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  • Qt 4.6 Adding objects and sub-objects to QWebView window object (C++ & Javascript)

    - by Cor
    I am working with Qt's QWebView, and have been finding lots of great uses for adding to the webkit window object. One thing I would like to do is nested objects... for instance: in Javascript I can... var api = new Object; api.os = new Object; api.os.foo = function(){} api.window = new Object(); api.window.bar = function(){} obviously in most cases this would be done through a more OO js-framework. This results in a tidy structure of: >>>api ------------------------------------------------------- - api Object {os=Object, more... } - os Object {} foo function() - win Object {} bar function() ------------------------------------------------------- Right now I'm able to extend the window object with all of the qtC++ methods and signals I need, but they all have 'seem' to have to be in a root child of "window". This is forcing me to write a js wrapper object to get the hierarchy that I want in the DOM. >>>api ------------------------------------------------------- - api Object {os=function, more... } - os_foo function() - win_bar function() ------------------------------------------------------- This is a pretty simplified example... I want objects for parameters, etc... Does anyone know of a way to pass an child object with the object that extends the WebFrame's window object? Here's some example code of how I'm adding the object: mainwindow.h #ifndef MAINWINDOW_H #define MAINWINDOW_H #include <QtGui/QMainWindow> #include <QWebFrame> #include "mainwindow.h" #include "happyapi.h" class QWebView; class QWebFrame; QT_BEGIN_NAMESPACE class MainWindow : public QMainWindow { Q_OBJECT public: MainWindow(QWidget *parent = 0); private slots: void attachWindowObject(); void bluesBros(); private: QWebView *view; HappyApi *api; QWebFrame *frame; }; #endif // MAINWINDOW_H mainwindow.cpp #include <QDebug> #include <QtGui> #include <QWebView> #include <QWebPage> #include "mainwindow.h" #include "happyapi.h" MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent) { view = new QWebView(this); view->load(QUrl("file:///Q:/example.htm")); api = new HappyApi(this); QWebPage *page = view->page(); frame = page->mainFrame(); attachWindowObject(); connect(frame, SIGNAL(javaScriptWindowObjectCleared()), this, SLOT(attachWindowObject())); connect(api, SIGNAL(win_bar()), this, SLOT(bluesBros())); setCentralWidget(view); }; void MainWindow::attachWindowObject() { frame->addToJavaScriptWindowObject(QString("api"), api); }; void MainWindow::bluesBros() { qDebug() << "foo and bar are getting the band back together!"; }; happyapi.h #ifndef HAPPYAPI_H #define HAPPYAPI_H #include <QObject> class HappyApi : public QObject { Q_OBJECT public: HappyApi(QObject *parent); public slots: void os_foo(); signals: void win_bar(); }; #endif // HAPPYAPI_H happyapi.cpp #include <QDebug> #include "happyapi.h" HappyApi::HappyApi(QObject *parent) : QObject(parent) { }; void HappyApi::os_foo() { qDebug() << "foo called, it want's it's bar back"; }; I'm reasonably new to C++ programming (coming from a web and python background). Hopefully this example will serve to not only help other new users, but be something interesting for a more experienced c++ programmer to elaborate on. Thanks for any assistance that can be provided. :)

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  • Problem with socket communication between C# and Flex

    - by Chris Lee
    Hi all, I am implementing a simulated b/s stock data system. I am using flex and c# for client and server sides. I found flash has a security policy and I handled the policy-file-request in my server code. But seems it doesn't work, because the code jumped out at "socket.Receive(b)" after connection. I've tried sending message on client in the connection handler, in that case the server can receive correct message. But the auto-generated "policy-file-request" can never be received, and the client can get no data sending from server. Here I put my code snippet. my ActionScript code: public class StockClient extends Sprite { private var hostName:String = "192.168.84.103"; private var port:uint = 55555; private var socket:XMLSocket; public function StockClient() { socket = new XMLSocket(); configureListeners(socket); socket.connect(hostName, port); } public function send(data:Object) : void{ socket.send(data); } private function configureListeners(dispatcher:IEventDispatcher):void { dispatcher.addEventListener(Event.CLOSE, closeHandler); dispatcher.addEventListener(Event.CONNECT, connectHandler); dispatcher.addEventListener(IOErrorEvent.IO_ERROR, ioErrorHandler); dispatcher.addEventListener(ProgressEvent.PROGRESS, progressHandler); dispatcher.addEventListener(SecurityErrorEvent.SECURITY_ERROR, securityErrorHandler); dispatcher.addEventListener(ProgressEvent.SOCKET_DATA, dataHandler); } private function closeHandler(event:Event):void { trace("closeHandler: " + event); } private function connectHandler(event:Event):void { trace("connectHandler: " + event); //following testing message can be received, but client can't invoke data handler //send("<policy-file-request/>"); } private function dataHandler(event:ProgressEvent):void { //never fired trace("dataHandler: " + event); } private function ioErrorHandler(event:IOErrorEvent):void { trace("ioErrorHandler: " + event); } private function progressHandler(event:ProgressEvent):void { trace("progressHandler loaded:" + event.bytesLoaded + " total: " + event.bytesTotal); } private function securityErrorHandler(event:SecurityErrorEvent):void { trace("securityErrorHandler: " + event); } } my C# code: const int PORT_NUMBER = 55555; const String BEGIN_REQUEST = "begin"; const String END_REQUEST = "end"; const String POLICY_REQUEST = "<policy-file-request/>\u0000"; const String POLICY_FILE = "<?xml version=\"1.0\"?>\n" + "<!DOCTYPE cross-domain-policy SYSTEM \"http://www.adobe.com/xml/dtds/cross-domain-policy.dtd\">\n" + "<cross-domain-policy> \n" + " <allow-access-from domain=\"*\" to-ports=\"55555\"/> \n" + "</cross-domain-policy>\u0000"; ................ private void startListening() { provider = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp); provider.Bind(new IPEndPoint(IPAddress.Parse("192.168.84.103"), PORT_NUMBER)); provider.Listen(10); isListened = true; while (isListened) { Socket socket = provider.Accept(); Console.WriteLine("connect!"); byte[] b = new byte[1024]; int receiveLength = 0; try { // code jump out at this statement receiveLength = socket.Receive(b); } catch (Exception e) { Debug.WriteLine(e.ToString()); } String request = System.Text.Encoding.UTF8.GetString(b, 0, receiveLength); Console.WriteLine("request:"+request); if (request == POLICY_REQUEST) { socket.Send(Encoding.UTF8.GetBytes(POLICY_FILE)); Console.WriteLine("response:" + POLICY_FILE); } else if (request == END_REQUEST) { Dispose(socket); } else { StartSocket(socket); break; } } } Sorry for the long code, please someone help with it, thanks a million

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  • Android: Get the X and Y coordinates of a TextView?

    - by Jep Knopz
    I am working now on a project. I have 2 draggable textView in a circle. I want to add those value inside the circle when the circle is drag over the other circle. the first option that I have is to get the X and Y of the circle, but I get it. Can anyone fix my code? Here is the Code: MainActivity public class MainActivity extends Activity { int windowwidth; int windowheight; TextView bola; TextView bola2; private float x; private float y; private android.widget.RelativeLayout.LayoutParams layoutParams; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); windowwidth = getWindowManager().getDefaultDisplay().getWidth(); windowheight = getWindowManager().getDefaultDisplay().getHeight(); bola = (TextView) findViewById(R.id.ball); bola2 = (TextView) findViewById(R.id.ball2); bola2.setOnTouchListener(new View.OnTouchListener() { @Override public boolean onTouch(View v, MotionEvent event) { // TODO Auto-generated method stub layoutParams = (RelativeLayout.LayoutParams) bola2 .getLayoutParams(); switch (event.getActionMasked()) { case MotionEvent.ACTION_DOWN: break; case MotionEvent.ACTION_MOVE: int x_cord = (int) event.getRawX(); int y_cord = (int) event.getRawY(); if (x_cord > windowwidth) { x_cord = windowwidth; } if (y_cord > windowheight) { y_cord = windowheight; } layoutParams.leftMargin = x_cord - 25; layoutParams.topMargin = y_cord - 75; bola2.setLayoutParams(layoutParams); break; default: break; } return true; } }); bola.setOnTouchListener(new View.OnTouchListener() { @Override public boolean onTouch(View v, MotionEvent event) { layoutParams = (RelativeLayout.LayoutParams) bola .getLayoutParams(); switch (event.getActionMasked()) { case MotionEvent.ACTION_DOWN: break; case MotionEvent.ACTION_MOVE: int x_cord = (int) event.getRawX(); int y_cord = (int) event.getRawY(); if (x_cord > windowwidth) { x_cord = windowwidth; } if (y_cord > windowheight) { y_cord = windowheight; } layoutParams.leftMargin = x_cord - 25; layoutParams.topMargin = y_cord - 75; bola.setLayoutParams(layoutParams); break; default: break; } // TODO Auto-generated method stub return true; } }); } @Override public boolean onCreateOptionsMenu(Menu menu) { getMenuInflater().inflate(R.menu.activity_main, menu); return true; }} Activity_main.xml <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" > <TextView android:id= "@+id/ball" android:background="@drawable/bgshape" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="1" tools:context=".MainActivity" /> <TextView android:id= "@+id/ball2" android:background="@drawable/bgshape" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="2" tools:context=".MainActivity" android:layout_x="60dp" android:layout_y="20dp" /> The bgshape.xml(for the circle) <?xml version="1.0" encoding="utf-8"?> <shape xmlns:android="http://schemas.android.com/apk/res/android" > <padding android:bottom="20dp" android:left="25dp" android:right="25dp" android:top="20dp" /> <stroke android:width="2dp" android:color="#000000" /> <solid android:color="#ffffff" /> <corners android:bottomLeftRadius="30dp" android:bottomRightRadius="30dp" android:topLeftRadius="30dp" android:topRightRadius="30dp" /> This code works well. Could anyone fix this so that I can add the value inside the circle when they hit each other?

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  • How do I get a Java to call data from the Internet? Where to even start??

    - by cdg
    Hello oh great wizards of all things android. I really need your help. Mostly because my little brain just doesn't know were to start. I am trying to pull data from the internet to make a widget for the home screen. I have the layout built: <?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/Layout" android:layout_width="fill_parent" android:layout_height="fill_parent" android:background="@drawable/widget_bg_normal" android:clipChildren="false" > <TextView android:id="@+id/text_view" android:layout_width="100px" android:layout_height="wrap_content" android:paddingTop="18px" android:layout_centerHorizontal="true" android:textSize="8px" android:text="158x154 Image downloaded from the internet goes here. Needs to be updated every evening at midnight or unless the button below is pressed. Now if I could only figure out exactly how to do this, life would be good." /> <Button android:id="@+id/new_button" android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="Get New" android:layout_below="@+id/scroll_image" android:layout_centerHorizontal="true" android:padding="0px" android:textSize="10px" android:height="8px" android:includeFontPadding="false" /> </RelativeLayout> Got the provider xml bulit: <?xml version="1.0" encoding="utf-8"?> <appwidget-provider xmlns:android="http://schemas.android.com/apk/res/android" android:minWidth="150dip" android:minHeight="150dip" android:updatePeriodMillis="10000" android:initialLayout="@layout/widget" /> The Manifest works great. <?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.dge.myandroid" android:versionCode="1" android:versionName="1.0"> <application android:icon="@drawable/icon" android:label="@string/app_name"> <activity android:name=".myactivty" android:label="@string/app_name"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> <!-- Widget --> <receiver android:name=".mywidget" android:label="@string/app_name" > <intent-filter> <action android:name="android.appwidget.action.APPWIDGET_UPDATE" /> </intent-filter> <meta-data android:name="android.appwidget.widgetprovider" android:resource="@xml/widgetprovider" /> </receiver> <!-- Widget End --> </application> <uses-permission android:name="android.permission.INTERNET" /> <uses-sdk android:minSdkVersion="7" /> </manifest> The data it is calling looks something like this when it is called. It basically goes to a website that uses php to random the image: <html><body bgcolor="#000000">center> <a href="http://www.website.com" target="_blank"> <img border="0" src="http://www.webiste.com//0.gif"></a> <img src="http://www.webiste.com" style="border:none;" /> </center></body></html> But here is were I am stuck. I just don't know where to start at all. The java is so far beyond my little head that I don't know what to do. package com.dge.myandroid; import android.appwidget.AppWidgetProvider; public class mywidget extends AppWidgetProvider { } The wiki example just confused me more. I just don't know where to begin. Please help.

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  • How do I add a namespace attribute to an element in JAXB when marshalling?

    - by Ryan Elkins
    I'm working with eBay's LMS (Large Merchant Services) and kept running into the error: org.xml.sax.SAXException: SimpleDeserializer encountered a child element, which is NOT expected, in something it was trying to deserialize. After alot of trial and error I traced the problem down. It turns out this works: <?xml version="1.0" encoding="UTF-8"?> <BulkDataExchangeRequests xmlns="urn:ebay:apis:eBLBaseComponents"> <Header> <Version>583</Version> <SiteID>0</SiteID> </Header> <AddFixedPriceItemRequest xmlns="urn:ebay:apis:eBLBaseComponents"> while this (what I've been sending) doesn't: <?xml version="1.0" encoding="UTF-8"?> <BulkDataExchangeRequests xmlns="urn:ebay:apis:eBLBaseComponents"> <Header> <Version>583</Version> <SiteID>0</SiteID> </Header> <AddFixedPriceItemRequest> The difference is the xml namespace attribute on the AddFixedPriceItemRequest . All of my XML is currently being marshalled via JAXB and I'm not sure what is the best way to go about adding a second xmlns attribute to a different element in my file. So that's the question. How do I add an xmlns attribute to another element in JAXB? UPDATE: package ebay.apis.eblbasecomponents; import javax.xml.bind.annotation.XmlAccessType; import javax.xml.bind.annotation.XmlAccessorType; import javax.xml.bind.annotation.XmlElement; import javax.xml.bind.annotation.XmlType; @XmlAccessorType(XmlAccessType.FIELD) @XmlType(name = "AddFixedPriceItemRequestType", propOrder = { "item" }) public class AddFixedPriceItemRequestType extends AbstractRequestType { @XmlElement(name = "Item") protected ItemType item; public ItemType getItem() { return item; } public void setItem(ItemType value) { this.item = value; } } Added class definition by request. UPDATE 2: Edited the above class like so to no effect: @XmlAccessorType(XmlAccessType.FIELD) @XmlType(namespace = "urn:ebay:apis:eBLBaseComponents", name = "AddFixedPriceItemRequestType", propOrder = { "item" }) public class AddFixedPriceItemRequestType UPDATE 3: Here is a snippet of the BulkDataExchangeRequestsType class. I tried throwing a namespace="urn:ebay:apis:eBLBaseComponents" into the @XmlElement for AddFixedPriceItemRequest but it didn't do anything. @XmlAccessorType(XmlAccessType.FIELD) @XmlType(name = "BulkDataExchangeRequestsType", propOrder = { "header", "addFixedPriceItemRequest" }) public class BulkDataExchangeRequestsType { @XmlElement(name = "Header") protected MerchantDataRequestHeaderType header; @XmlElement(name = "AddFixedPriceItemRequest") protected List<AddFixedPriceItemRequestType> addFixedPriceItemRequest; UPDATE 4: Here's the hideous chunk of code that is updating the xml after marshalling for me. This is currently working although I'm not particulary proud of it. DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); dbf.setNamespaceAware(true); DocumentBuilder db = dbf.newDocumentBuilder(); Document doc = db.newDocument(); marshaller.marshal(request, doc); NodeList nodes = doc.getChildNodes(); nodes = nodes.item(0).getChildNodes(); for(int i = 0; i < nodes.getLength(); i++){ Node node = nodes.item(i); if (!node.getNodeName().equals("Header")){ ((Element)node).setAttribute("xmlns", "urn:ebay:apis:eBLBaseComponents"); } } Update 5: For anyone else that runs into this problem with eBay and wonders why - The reasoning behind this most likely has to do with how eBay is handling these requests. The BulkDataExchange probably takes the XML payload, breaks it up, and send the pieces out to the Merchant or Trading API. The inner pieces of the payload then do not have the namespace and the get the error. This is a guess on my part but I wouldn't be surprised if this is what was going on behind the scenes. Thanks for all the help everyone.

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  • How to manage a MotionEvent going from one View to another?

    - by Darren
    I have a SurfaceView that takes up part of the screen, and some buttons along the bottom. When a button is pressed and the user drags, I want to be able to drag a picture (based on the button) onto the SurfaceView and have it drawn there. I want to be able to use clickListeners and the like, and not just have a giant SurfaceView with me writing code to detect where the user pressed and if it's a button, etc. I have somewhat of a solution, but it seems a bit of a hack to me. What is the best way to accomplish this using the framework intelligently? Part of my XML: <RelativeLayout android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" android:background="@drawable/background"> <!-- Place buttons along the bottom --> <RelativeLayout android:id="@+id/bottom_bar" android:orientation="horizontal" android:layout_width="fill_parent" android:layout_height="40dip" android:layout_alignParentBottom="true" android:background="@null"> <ImageButton android:id="@+id/btn_1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_centerVertical="true" android:background="@null" android:src="@drawable/btn_1"> </ImageButton> <!-- More buttons here... --> </RelativeLayout> <!-- Place the SurfaceView in a frame so we can stack on top of it --> <FrameLayout android:layout_width="fill_parent" android:layout_height="0px" android:layout_weight="1" android:layout_above="@id/bottom_bar"> <com.project.question.MySurfaceView android:id="@+id/my_view" android:layout_width="fill_parent" android:layout_height="fill_parent" /> </FrameLayout> And the relevant Java code in MySurfaceView, which extends SurfaceView. mTouchX and Y are used in the onDraw method to draw the image: @Override public boolean onTouchEvent(MotionEvent event){ mTouchX = (int) event.getX(); mTouchY = (int) event.getY(); return true; } public void onButtonTouchEvent(MotionEvent event){ event.setLocation(event.getX(), event.getY() + mScreenHeight); onTouchEvent(event); } Finally, the activity: @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); requestWindowFeature(Window.FEATURE_NO_TITLE); setContentView(R.layout.my_surface); mView = (MySurfaceView) findViewById(R.id.my_view); mSurfaceHeight = mView.getHeight(); mBtn = (ImageButton) findViewById(R.id.btn_1); mBtn.setOnTouchListener(mTouchListener); } OnTouchListener mTouchListener = new OnTouchListener() { public boolean onTouch(View v, MotionEvent event) { int [] location = new int[2]; v.getLocationOnScreen(location); event.setLocation(event.getX() + location[0], event.getY()); mView.onButtonTouchEvent(event); return true; } }; Strangely, one has to add to the x-coordinate in the activity, then add to the y coordinate in the View. Otherwise, it doesn't show up in the correct position. If you add nothing, something drawn using mTouchX and mTouchY will show up in the upper left corner of the SurfaceView. Any direction would be greatly appreciated. If I'm going about this completely the wrong way, that would be good information too.

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  • Synchronizing issue: I want the main thread to be run before another thread but it sometimes doesn´t

    - by Rox
    I have done my own small concurrency framework (just for learning purposes) inspired by the java.util.concurrency package. This is about the Callable/Future mechanism. My code below is the whole one and is compilable and very easy to understand. My problem is that sometimes I run into a deadlock where the first thread (the main thread) awaits for a signal from the other thread. But then the other thread has already notified the main thread before the main thread went into waiting state, so the main thread cannot wake up. FutureTask.get() should always be run before FutureTask.run() but sometimes the run() method (which is called by new thread) runs before the get() method (which is called by main thread). I don´t know how I can prevent that. This is a pseudo code of how I want the two threads to be run. //From main thread: Executor.submit().get() (in get() the main thread waits for new thread to notify) ->submit() calls Executor.execute(FutureTask object) -> execute() starts new thread -> new thread shall notify `main thread` I cannot understand how the new thread can start up and run faster than the main thread that actually starts the new thread. Main.java: public class Main { public static void main(String[] args) { new ExecutorServiceExample(); } public Main() { ThreadExecutor executor = new ThreadExecutor(); Integer i = executor.submit(new Callable<Integer>() { @Override public Integer call() { return 10; } }).get(); System.err.println("Value: "+i); } } ThreadExecutor.java: public class ThreadExecutor { public ThreadExecutor() {} protected <V> RunnableFuture<V> newTaskFor(Callable c) { return new FutureTask<V>(c); } public <V> Future<V> submit(Callable<V> task) { if (task == null) throw new NullPointerException(); RunnableFuture<V> ftask = newTaskFor(task); execute(ftask); return ftask; } public void execute(Runnable r) { new Thread(r).start(); } } FutureTask.java: import java.util.concurrent.locks.Condition; import java.util.concurrent.locks.ReentrantLock; import java.util.logging.Level; import java.util.logging.Logger; public class FutureTask<V> implements RunnableFuture<V> { private Callable<V> callable; private volatile V result; private ReentrantLock lock = new ReentrantLock(); private Condition condition = lock.newCondition(); public FutureTask(Callable callable) { if (callable == null) throw new NullPointerException(); this.callable = callable; } @Override public void run() { acquireLock(); System.err.println("RUN"+Thread.currentThread().getName()); V v = this.callable.call(); set(v); condition.signal(); releaseLock(); } @Override public V get() { acquireLock(); System.err.println("GET "+Thread.currentThread().getName()); try { condition.await(); } catch (InterruptedException ex) { Logger.getLogger(FutureTask.class.getName()).log(Level.SEVERE, null, ex); } releaseLock(); return this.result; } public void set(V v) { this.result = v; } private void acquireLock() { lock.lock(); } private void releaseLock() { lock.unlock(); } } And the interfaces: public interface RunnableFuture<V> extends Runnable, Future<V> { @Override void run(); } public interface Future<V> { V get(); } public interface Callable<V> { V call(); }

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  • ListView with button and check mark?

    - by jgelderloos
    So I have looked through a lot of other answers but have not been able to get my app to work how I want it. I basically want the list view that has the text and check mark to the right, but then an addition button to the left. Right now my list view shows up but the check image is never changed. Selector: <?xml version="1.0" encoding="utf-8"?> <selector xmlns:android="http://schemas.android.com/apk/res/android"> <item android:state_selected="true" android:drawable="@drawable/accept_on" /> <item android:drawable="@drawable/accept" /> </selector> Row xml: <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/layout" android:orientation="horizontal" android:layout_width="fill_parent" android:layout_height="fill_parent" android:padding="10dp" android:background="#EEE"> <ImageButton android:id="@+id/goToMapButton" android:src="@drawable/go_to_map" android:layout_width="wrap_content" android:layout_height="wrap_content" android:gravity="left" /> <TextView android:id="@+id/itemName" android:layout_width="fill_parent" android:layout_height="fill_parent" android:gravity="center_vertical" android:textColor="#000000" android:layout_marginTop="5dp" android:layout_marginBottom="5dp" android:layout_weight="1" /> <Button android:id="@+id/checkButton" android:background="@drawable/item_selector" android:layout_width="wrap_content" android:layout_height="wrap_content" android:gravity="right" /> </LinearLayout> MapAdapter: import android.content.Context; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.ArrayAdapter; import android.widget.Button; import android.widget.ImageButton; import android.widget.LinearLayout; import android.widget.TextView; public class MapAdapter extends ArrayAdapter<String>{ Context context; int layoutResourceId; String data[] = null; LayoutInflater inflater; LinearLayout layout; public MapAdapter(Context context, int layoutResourceId, String[] data) { super(context, layoutResourceId, data); this.layoutResourceId = layoutResourceId; this.context = context; this.data = data; inflater = LayoutInflater.from(context); } @Override public String getItem(int position) { return data[position]; } @Override public View getView(int position, View convertView, ViewGroup parent) { ViewHolder holder = new ViewHolder(); if(convertView == null) { convertView = inflater.inflate(R.layout.map_item_row, null); layout = (LinearLayout)convertView.findViewById(R.id.layout); holder.map = (ImageButton)convertView.findViewById(R.id.goToMapButton); holder.name = (TextView)convertView.findViewById(R.id.itemName); //holder.check = (Button)convertView.findViewById(R.id.checkButton); convertView.setTag(holder); } else { holder = (ViewHolder) convertView.getTag(); } layout.setBackgroundColor(0x00000004); holder.name.setText(getItem(position)); return convertView; } static class ViewHolder { ImageButton map; TextView name; Button check; } }

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  • NullPointerException in ItemizedOverlay.getIndexToDraw

    - by lyricsboy
    I have a relatively simple MapActivity that I'm trying to make display a list of "camps" within a given map region. I've created a custom subclass of OverlayItem called CampOverlayItem, a custom ItemizedOverlay called CampsOverlay that returns CampOverlayItems, and of course a MapActivity subclass that populates the map. I'm pulling the overlay data from a database using an AsyncTask as created in my activity. The AsyncTask is triggered from a ViewTreeObserver.OnGlobalLayoutListener attached to the MapView. In the onPostExecute method of the AsyncTask, I create a new instance of my CampsOverlay class and pass it a list of the camps returned from the database (which are fetched in doInBackground). I then call: mapView.getOverlays().add(newOverlay); where newOverlay is the CampsOverlay I just created. All of this code runs without error, but when the Map tries to draw itself, I get a NullPointerException with the following stack trace: java.lang.NullPointerException at com.google.android.maps.ItemizedOverlay.getIndexToDraw(ItemizedOverlay.java: 211) at com.google.android.maps.ItemizedOverlay.draw(ItemizedOverlay.java:240) at com.google.android.maps.Overlay.draw(Overlay.java:179) at com.google.android.maps.OverlayBundle.draw(OverlayBundle.java: 42) at com.google.android.maps.MapView.onDraw(MapView.java:476) at android.view.View.draw(View.java:6274) at android.view.ViewGroup.drawChild(ViewGroup.java:1526) at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1256) at android.view.ViewGroup.drawChild(ViewGroup.java:1524) at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1256) at android.view.View.draw(View.java:6277) at android.widget.FrameLayout.draw(FrameLayout.java:352) at android.view.ViewGroup.drawChild(ViewGroup.java:1526) at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1256) at android.view.ViewGroup.drawChild(ViewGroup.java:1524) at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1256) at android.view.ViewGroup.drawChild(ViewGroup.java:1524) at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1256) at android.view.ViewGroup.drawChild(ViewGroup.java:1524) at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1256) at android.view.ViewGroup.drawChild(ViewGroup.java:1524) at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1256) at android.view.View.draw(View.java:6277) at android.widget.FrameLayout.draw(FrameLayout.java:352) at android.view.ViewGroup.drawChild(ViewGroup.java:1526) at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1256) at android.view.View.draw(View.java:6277) at android.widget.FrameLayout.draw(FrameLayout.java:352) at com.android.internal.policy.impl.PhoneWindow $DecorView.draw(PhoneWindow.java:1883) at android.view.ViewRoot.draw(ViewRoot.java:1332) at android.view.ViewRoot.performTraversals(ViewRoot.java:1097) at android.view.ViewRoot.handleMessage(ViewRoot.java:1613) at android.os.Handler.dispatchMessage(Handler.java:99) at android.os.Looper.loop(Looper.java:123) at android.app.ActivityThread.main(ActivityThread.java:4203) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:521) at com.android.internal.os.ZygoteInit $MethodAndArgsCaller.run(ZygoteInit.java:791) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:549) at dalvik.system.NativeStart.main(Native Method) Because it seems particularly relevant, here is the code for my ItemizedOverlay subclass: public class CampsOverlay extends ItemizedOverlay<CampOverlayItem> { private ArrayList<Camp> camps = null; public CampsOverlay(Drawable defaultMarker, ArrayList<Camp> theCamps) { super(defaultMarker); this.camps = theCamps; } @Override protected CampOverlayItem createItem(int i) { Camp camp = camps.get(i); CampOverlayItem item = new CampOverlayItem(camp); return item; } @Override protected boolean onTap(int index) { // TODO Auto-generated method stub return super.onTap(index); } @Override public int size() { return camps.size(); } } Does anyone have any idea what could be happening here? I've attempted to verify that everything I have control over is non-null. I can provide more code if necessary.

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  • Radix sort in java help

    - by endif
    Hi i need some help to improve my code. I am trying to use Radixsort to sort array of 10 numbers (for example) in increasing order. When i run the program with array of size 10 and put 10 random int numbers in like 70 309 450 279 799 192 586 609 54 657 i get this out: 450 309 192 279 54 192 586 657 54 609 Don´t see where my error is in the code. class IntQueue { static class Hlekkur { int tala; Hlekkur naest; } Hlekkur fyrsti; Hlekkur sidasti; int n; public IntQueue() { fyrsti = sidasti = null; } // First number in queue. public int first() { return fyrsti.tala; } public int get() { int res = fyrsti.tala; n--; if( fyrsti == sidasti ) fyrsti = sidasti = null; else fyrsti = fyrsti.naest; return res; } public void put( int i ) { Hlekkur nyr = new Hlekkur(); n++; nyr.tala = i; if( sidasti==null ) f yrsti = sidasti = nyr; else { sidasti.naest = nyr; sidasti = nyr; } } public int count() { return n; } public static void radixSort(int [] q, int n, int d){ IntQueue [] queue = new IntQueue[n]; for (int k = 0; k < n; k++){ queue[k] = new IntQueue(); } for (int i = d-1; i >=0; i--){ for (int j = 0; j < n; j++){ while(queue[j].count() != 0) { queue[j].get(); } } for (int index = 0; index < n; index++){ // trying to look at one of three digit to sort after. int v=1; int digit = (q[index]/v)%10; v*=10; queue[digit].put(q[index]); } for (int p = 0; p < n; p++){ while(queue[p].count() != 0) { q[p] = (queue[p].get()); } } } } } I am also thinking can I let the function take one queue as an argument and on return that queue is in increasing order? If so how? Please help. Sorry if my english is bad not so good in it. Please let know if you need more details. import java.util.Random; public class RadTest extends IntQueue { public static void main(String[] args) { int [] q = new int[10]; Random r = new Random(); int t = 0; int size = 10; while(t != size) { q[t] = (r.nextInt(1000)); t++; } for(int i = 0; i!= size; i++) { System.out.println(q[i]); } System.out.println("Radad: \n"); radixSort(q,size,3); for(int i = 0; i!= size; i++) { System.out.println(q[i]); } } } Hope this is what you were talking about...

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  • Outer class jframe is not hiding when calling the inner class jframe

    - by user2909960
    When i am calling the inner jframe, it is called, but outer jframe is not hiding. instead it gets overlapped. so what will be the solution for this. Is there any way to get out of this. As i tried when i am calling the inner class frame, the outer class frame is also called, and it is not hidden. package com.exp.example; import java.awt.Color; import java.awt.Container; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JTextField; @SuppressWarnings("serial") public class A extends JFrame implements ActionListener { JFrame rframe = new JFrame(); JLabel CFirstName; JTextField Cfname; JButton jbsubmit; Container cp; public A() { rframe.setSize(500, 200); rframe.setLocationRelativeTo(null); cp = getContentPane(); cp.setLayout(null); setSize(550, 300); rframe.setTitle("Outer Frame"); cp.setBackground(new Color(140, 180, 180)); CFirstName = new JLabel("First Name"); Cfname = new JTextField(10); jbsubmit = new JButton("PREVIEW"); CFirstName.setBounds(10, 20, 100, 35); Cfname.setBounds(150, 20, 150, 25); jbsubmit.setBounds(190, 110, 92, 25); cp.add(CFirstName); cp.add(Cfname); cp.add(jbsubmit); jbsubmit.addActionListener(this); rframe.add(cp); rframe.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); rframe.setVisible(true); } public void actionPerformed(ActionEvent ae) { String action = ae.getActionCommand(); if (action == "PREVIEW") { /* Write the code here * When we click on preview button the frame of outer class(class A) gets * deactivated(closed) and inner frame, frame of inner class(class B) gets visible. * it should not be overlapped. */ /* My Code */ new B(); rframe.setVisible(false); } } public class B { JFrame frm = new JFrame(); Container cp; public B() { frm.setSize(500, 200); frm.setLocationRelativeTo(null); cp = getContentPane(); cp.setLayout(null); setSize(550, 300); frm.setTitle("Inner Frame"); cp.setBackground(new Color(140, 180, 180)); JLabel cpn = new JLabel("hello"); cpn.setBounds(10, 20, 100, 35); cp.add(cpn); frm.add(cp); frm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frm.setVisible(true); } } public static void main(String[] args) { new A(); } }

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  • How can I pass extra parameters to the routeMatch object?

    - by Marcos Garcia
    I'm trying to unit test a controller, but can't figure out how to pass some extra parameters to the routeMatch object. I followed the posts from tomoram at http://devblog.x2k.co.uk/unit-testing-a-zend-framework-2-controller/ and http://devblog.x2k.co.uk/getting-the-servicemanager-into-the-test-environment-and-dependency-injection/, but when I try to dispatch a request to /album/edit/1, for instance, it throws the following exception: Zend\Mvc\Exception\DomainException: Url plugin requires that controller event compose a router; none found Here is my PHPUnit Bootstrap: class Bootstrap { static $serviceManager; static $di; static public function go() { include 'init_autoloader.php'; $config = include 'config/application.config.php'; // append some testing configuration $config['module_listener_options']['config_static_paths'] = array(getcwd() . '/config/test.config.php'); // append some module-specific testing configuration if (file_exists(__DIR__ . '/config/test.config.php')) { $moduleConfig = include __DIR__ . '/config/test.config.php'; array_unshift($config['module_listener_options']['config_static_paths'], $moduleConfig); } $serviceManager = Application::init($config)->getServiceManager(); self::$serviceManager = $serviceManager; // Setup Di $di = new Di(); $di->instanceManager()->addTypePreference('Zend\ServiceManager\ServiceLocatorInterface', 'Zend\ServiceManager\ServiceManager'); $di->instanceManager()->addTypePreference('Zend\EventManager\EventManagerInterface', 'Zend\EventManager\EventManager'); $di->instanceManager()->addTypePreference('Zend\EventManager\SharedEventManagerInterface', 'Zend\EventManager\SharedEventManager'); self::$di = $di; } static public function getServiceManager() { return self::$serviceManager; } static public function getDi() { return self::$di; } } Bootstrap::go(); Basically, we are creating a Zend\Mvc\Application environment. My PHPUnit_Framework_TestCase is enclosed in a custom class, which goes like this: abstract class ControllerTestCase extends TestCase { /** * The ActionController we are testing * * @var Zend\Mvc\Controller\AbstractActionController */ protected $controller; /** * A request object * * @var Zend\Http\Request */ protected $request; /** * A response object * * @var Zend\Http\Response */ protected $response; /** * The matched route for the controller * * @var Zend\Mvc\Router\RouteMatch */ protected $routeMatch; /** * An MVC event to be assigned to the controller * * @var Zend\Mvc\MvcEvent */ protected $event; /** * The Controller fully qualified domain name, so each ControllerTestCase can create an instance * of the tested controller * * @var string */ protected $controllerFQDN; /** * The route to the controller, as defined in the configuration files * * @var string */ protected $controllerRoute; public function setup() { parent::setup(); $di = \Bootstrap::getDi(); // Create a Controller and set some properties $this->controller = $di->newInstance($this->controllerFQDN); $this->request = new Request(); $this->routeMatch = new RouteMatch(array('controller' => $this->controllerRoute)); $this->event = new MvcEvent(); $this->event->setRouteMatch($this->routeMatch); $this->controller->setEvent($this->event); $this->controller->setServiceLocator(\Bootstrap::getServiceManager()); } public function tearDown() { parent::tearDown(); unset($this->controller); unset($this->request); unset($this->routeMatch); unset($this->event); } } And we create a Controller instance and a Request with a RouteMatch. The code for the test: public function testEditActionWithGetRequest() { // Dispatch the edit action $this->routeMatch->setParam('action', 'edit'); $this->routeMatch->setParam('id', $album->id); $result = $this->controller->dispatch($this->request, $this->response); // rest of the code isn't executed } I'm not sure what I'm missing here. Can it be any configuration for the testing bootstrap? Or should I pass the parameters in some other way? Or am I forgetting to instantiate something?

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  • Servlet stops without giving any exception

    - by Fahim
    Hi, I have implemented a Servlet hosted on Tomcat 6 server on Mandriva Linux. I have been able to make the client communicate with the Servlet. In response to a request the Servlet tries to instantiate a another class (named KalmanFilter) located in the same directory. The KalmanFilter tries to create four Matrices (using Jama Matrix package). But at this point Servlet stops without giving any exception ! However, from another test code in the same directory I have been able to create instance of KalmanFilter class, and proceed without any error. The problem occurs only when my Servlet tries to instantiate the KalmanFilter class and create the matrices. Any idea? Below are the codes: MyServlet.java import javax.servlet.*; import javax.servlet.http.*; import java.io.*; import java.util.*; public class MyServlet extends HttpServlet { public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException{ doGet(request, response); } public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException{ PrintWriter out = null; //response.getWriter(); try{ System.out.println("creating new KalmanFilter"); KalmanFilter filter = new KalmanFilter(); out = response.getWriter(); out.print("filter created"); }catch(Exception ex){ ex.printStackTrace(); System.out.println("Exception in doGet(): " + ex.getMessage()); ex.printStackTrace(out); } } } KalmanFilter.java import Jama.Matrix; public class KalmanFilter { protected Matrix X, X0; protected Matrix F, Q; //protected Matrix F, B, U, Q; protected Matrix H, R; protected Matrix P, P0; private final double EPSILON = 0.001; public KalmanFilter(){ System.out.println("from constructor of KalmanFilter"); createInitialMatrices(); } private void createInitialMatrices(){ System.out.println("from KalmanFilter.createInitialMatrices()"); double[][] pVals = { {1.0, 0.0}, {0.0, 1.0} }; double[][] qVals = { {EPSILON, EPSILON}, {EPSILON, EPSILON} }; double[][] hVals = { {1.0, 0.0}, {0.0, 1.0}, {1.0, 0.0}, {0.0, 1.0} }; double[][] xVals = { {0.0}, {0.0}, }; System.out.println("creating P Q H X matrices in createInitialMatrices()"); try{ this.P = new Matrix(pVals); System.out.println("created P matrix in createInitialMatrices()"); this.Q = new Matrix(qVals); System.out.println("created Q matrix in createInitialMatrices()"); this.H = new Matrix(hVals); System.out.println("created H matrix in createInitialMatrices()"); this.X = new Matrix(xVals); System.out.println("created X matrix in createInitialMatrices()"); System.out.println("created P Q H X matrices in createInitialMatrices()"); }catch(Exception e){ System.out.println("Exception from createInitialMatrices()"+ e.getMessage()); e.printStackTrace(); } System.out.println("returning from createInitialMatrices()"); } }

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  • Which option do you like the most?

    - by spderosso
    I need to show a list of movies ordered by the date they were registered in the system and the amount of comments users have made about them. E.g: Title | Register Date | # of comments Gladiator | 02-01-2010 | 30 Matrix | 01-02-2010 | 20 It is a web application that follows MVC. So, I have the object "Movie", there is a MovieManager interface that is used for retrieving/persisting data to the database and a servlet RecentlyAddedMovies.java that forwards to a .jsp to render the list. I will explain my problem by showing an example of how I am doing another similar task: Showing top ranked movies. Regarding the MovieManager: /** * Returns a collection of the x best-ranked movies * @param x the amount of movies to return * @return A collection of movies * @throws SQLException */ public Collection<Movie> getTopX(int x) throws SQLException; The servlet: public class Top5 extends HttpServlet{ @Override protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { MovieManager movManager = JDBCMovieManager.getInstance(); try { req.setAttribute("movies", movManager.getTopX(5)); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } req.getRequestDispatcher("listMovies.jsp").forward(req, resp); } } And the listMovies.jsp has is some place something like: <c:forEach var="movie" items="${movies}"> ... <c:out value="${movie.title}"/> ... </c:forEach> The difference between the top5 problem and the problem I am trying to solve is that with the top5 thing all the data I needed to show in the view where part of the "Movie" object, so the MovieManager simply returned a Collection of Movies. Now, the MovieManager must retrieve an ordered list of (Movie, # of comments). The Movie object has a collection of Comment associated but of course, it lacks an instance variable with the length of that collection. The following things came into my mind: a) Create a MovieView object or something like that, that is only used by the "View" and "Controller" layer of the MVC which is not part of the "Model" in the sense that is used only for easy retrieval and display of information. This MovieView object will have a title, registerDate and # of Comments so the thing would look something like this: /** * Returns a collection of the x most recently added movies * @param x the amount of movies to return * @return A collection of movies * @throws SQLException */ public Collection<Movie2> getXRecentlyAddedMovies(int x) throws SQLException; The .jsp: <c:forEach var="movie2" items="${movies2}"> ... <c:out value="${movie2.title}"/> <c:out value="${movie2.registerDate}"/> <c:out value="${movie2.noOfComments}"/> ... </c:forEach> b) Add to the Collection the movie has, empty Comments (there is no actual need to retrieve all the comment data from the database) so that the comment's collection.size() will show the number of comments that movie has. (This sounds horrible to me) c) Add to the "Movie" object an instance field noOfComments with the setter and getter that will help with this type of cases even if, looking only from the object point of view, it is a redundant field since it already has a Collection that is ".size()"able . d) Make the MovieManager retrieve some structure like a Map or a Collection of a two component array or something like that that will contain both a Movie object and the associated number of comments and with JSLT iterate over it and show it accordingly.

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  • My google map android app keeps crashing

    - by Manny264
    I have followed about two tutorials from vogella and some other tutorial that looked similar...very similar but to no avail. I load the app on my nexus 7 and it just crashes "Unfortunately MyMapView has stopped working" on launch.This is the manifest: ` <uses-sdk android:minSdkVersion="17" android:targetSdkVersion="17" /> <uses-feature android:glEsVersion="0x00020000" android:required="true"/> <uses-permission android:name="android.permission.INTERNET" /> <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" /> <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" /> <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /> <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/> <uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES"/> <application android:allowBackup="true" android:icon="@drawable/ic_launcher" android:label="@string/app_name" android:theme="@style/AppTheme" > <uses-library android:name="com.google.android.maps" /> <activity android:name="com.macmozart.mymapview.MainActivity" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> <meta-data android:name="com.google.android.maps.v2.API_KEY" android:value="AIzaSyBZ1Bt7rjB863Jy-B05zls6k8XZsBGQ6-4" /> </application> ` Followed by my main layout: <fragment android:id="@+id/map" android:layout_width="match_parent" android:layout_height="match_parent" class="com.google.android.gms.maps.MapFragment" /> and finally my java class: package com.macmozart.mymapview; import android.app.Activity; import android.os.Bundle; import com.google.android.gms.maps.CameraUpdateFactory; import com.google.android.gms.maps.GoogleMap; import com.google.android.gms.maps.MapFragment; import com.google.android.gms.maps.model.BitmapDescriptorFactory; import com.google.android.gms.maps.model.LatLng; import com.google.android.gms.maps.model.Marker; import com.google.android.gms.maps.model.MarkerOptions; import com.google.android.maps.*; public class MainActivity extends Activity { static final LatLng HAMBURG = new LatLng(53.558, 9.927); static final LatLng KIEL = new LatLng(53.551, 9.993); private GoogleMap map; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); map = ((MapFragment) getFragmentManager().findFragmentById(R.id.map)) .getMap(); if (map != null) { Marker hamburg = map.addMarker(new MarkerOptions() .position(HAMBURG).title("Hamburg")); Marker kiel = map.addMarker(new MarkerOptions() .position(KIEL) .title("Kiel") .snippet("Kiel is cool") .icon(BitmapDescriptorFactory .fromResource(R.drawable.ic_launcher))); map.moveCamera(CameraUpdateFactory.newLatLngZoom(HAMBURG, 15)); // Zoom in, animating the camera. map.animateCamera(CameraUpdateFactory.zoomTo(10), 2000, null); } } } Any idea what im doing wrong I really need this to work

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  • JAXB marshals XML differently to OutputStream vs. StringWriter

    - by Andy
    I apologize if this has been answered, but the search terms I have been using (i.e. JAXB @XmlAttribute condensed or JAXB XML marshal to String different results) aren't coming up with anything. I am using JAXB to un/marshal objects annotated with @XmlElement and @XmlAttribute annotations. I have a formatter class which provides two methods -- one wraps the marshal method and accepts the object to marshal and an OutputStream, the other just accepts the object and returns the XML output as a String. Unfortunately, these methods do not provide the same output for the same objects. When marshaling to a file, simple object fields internally marked with @XmlAttribute are printed as: <element value="VALUE"></element> while when marshaling to a String, they are: <element value="VALUE"/> I would prefer the second format for both cases, but I am curious as to how to control the difference, and would settle for them being the same regardless. I even created one static marshaller that both methods use to eliminate different instance values. The formatting code follows: /** Marker interface for classes which are listed in jaxb.index */ public interface Marshalable {} /** Local exception class */ public class XMLMarshalException extends BaseException {} /** Class which un/marshals objects to XML */ public class XmlFormatter { private static Marshaller marshaller = null; private static Unmarshaller unmarshaller = null; static { try { JAXBContext context = JAXBContext.newInstance("path.to.package"); marshaller = context.createMarshaller(); marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true); marshaller.setProperty(Marshaller.JAXB_ENCODING, "UTF-8"); unmarshaller = context.createUnmarshaller(); } catch (JAXBException e) { throw new RuntimeException("There was a problem creating a JAXBContext object for formatting the object to XML."); } } public void marshal(Marshalable obj, OutputStream os) throws XMLMarshalException { try { marshaller.marshal(obj, os); } catch (JAXBException jaxbe) { throw new XMLMarshalException(jaxbe); } } public String marshalToString(Marshalable obj) throws XMLMarshalException { try { StringWriter sw = new StringWriter(); marshaller.marshal(obj, sw); } catch (JAXBException jaxbe) { throw new XMLMarshalException(jaxbe); } } } /** Example data */ @XmlType @XmlAccessorType(XmlAccessType.FIELD) public class Data { @XmlAttribute(name = value) private String internalString; } /** Example POJO */ @XmlType @XmlRootElement(namespace = "project/schema") @XmlAccessorType(XmlAccessType.FIELD) public class Container implements Marshalable { @XmlElement(required = false, nillable = true) private int number; @XmlElement(required = false, nillable = true) private String word; @XmlElement(required = false, nillable = true) private Data data; } The result of calling marshal(container, new FileOutputStream("output.xml")) and marshalToString(container) are as follows: Output to file <?xml version="1.0" encoding="UTF-8" standalone="yes"?> <ns2:container xmlns:ns2="project/schema"> <number>1</number> <word>stackoverflow</word> <data value="This is internal"></data> </ns2:container> and Output to String <?xml version="1.0" encoding="UTF-8" standalone="yes"?> <ns2:container xmlns:ns2="project/schema"> <number>1</number> <word>stackoverflow</word> <data value="This is internal"/> </ns2:container>

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