Search Results

Search found 33297 results on 1332 pages for 'java java ee'.

Page 803/1332 | < Previous Page | 799 800 801 802 803 804 805 806 807 808 809 810  | Next Page >

  • How do I implement a listener pattern over RMI using Spring?

    - by predhme
    So here is a generalized version of our application desgin: @Controller public class MyController { @Autowired private MyServiceInterface myServiceInterface; @RequestMapping("/myURL") public @ResponseBody String doSomething() { MyListenerInterface listener = new MyListenerInterfaceImpl(); myServiceInterface.doThenCallListener(listener); // do post stuff } } public interface MyListenerInterface { public void callA(); public void callB(); } public class MyListenerInterfaceImpl implements MyListenerInterface { // ... omitted for clarity } public interface MyServiceInterface { public void doThenCallListener(MyListenerInterface listener); } public class MyServiceImpl { public void doThenCallListener(MyListenerInterface listener) { // do stuff listener.callA(); } } Basically I have a controller that is being called via AJAX in which I am looking to return a response as a string. However, I need to make a call to the backend (MyServiceInterface). That guy is exposed through RMI by using Spring (man that was easy). But the service method as described requires a listener to be registered for invokation completion purposes. So what I assume I need to achieve is transparently to the backend make it so that when the listener methods are called, really the call is going over RMI. I would have thought Spring would have a simple way to wrap a POJO (not a service singleton) with RMI calls. I looked through their documentation but they had nothing besides exposing services via RMI. Could someone point me in the right direction?

    Read the article

  • JSF don't find component in view root with the form id

    - by kenzokujpn
    I have a t:inputFileUpload inside the form, in the html of the display page the id of this component is form:inputFile but when I tried to get the component from the view root using "form:inputFile" the return is null, but when the "form:" is removed the return is the component. The component don't set the value in my managed bean, someone have this problem? EDIT: <h:form id="form" enctype="multipart/form-data"> <t:inputFileUpload id="inputFile" size="40" value="#{managedBean.inputFile}"/> </h:form> In the managed bean: private UploadedFile inputFile; with the gets and sets provided by Eclipse. //This method scans the view root and returns the component with the id passed as parameter findComponentInRoot("form:inputFile"); This returns null, but when I use: //This method scans the view root and returns the component with the id passed as parameter findComponentInRoot("inputFile"); The return is the component I'm looking for, but when I use the View Source in Internet Explorer the id of this component is "form:inputFile". I don't know if this is related, but the component don't set the value in my managed bean and it's strange the fact that the id of the component is different from the HTML source. I'm using JSF 1.2 Mojarra. Someone else has this problem? Or know why this happens?

    Read the article

  • Tomcat: recommandations for logging

    - by WizardOfOdds
    I've read several questions here concerning Tomcat and logging but I still really don't understand the "bigger picture", hence my question: How and where are my Webapps supposed to do their logging? By default on my setup Tomcat 6.0.20 logs go in the following file/appender: ./apache-tomcat-6.0.20/logs/catalina.out Am I suppose to have my webapps also log to this file/appender? Let say my case is trivially simple and I've got just one servlet: import ... // What do I import here in order to be able to log? public class SOServlet extends HttpServlet { public void doGet( final HttpServletRequest request, final HttpServletResponse response ) throws IOException, ServletException { ... // I want to log here, what do I write? What are the gotchas knowing that there are more than one webapp running on the same Tomcat? (apparently from reading the various questions there are many gotchas). What about the .war, do I need to put log4j/sl4f/commons-logging/whatever in my .war?

    Read the article

  • Android Convert Video To MP4

    - by Isaac Waller
    I have a Android app. It recieves videos in .flv format which is unplayable by the Android phone. I was wondering how to convert the file to MP4. I could use FFMPEG, but I do not know how I would get it onto the phone, and how it would work on multiple phones if it was compiled for a single one.

    Read the article

  • getting number from console!

    - by Johanna
    Hi this is my method that will be called if I want to get a number from user. but if the user also enter a right number just the "else" part will be run ,why? please help me tahnsk. public static int chooseTheTypeOfSorting() { System.out.println("Enter 0 for merge sorting OR enter 1 for bubble sorting"); int numberFromConsole = 0; try { InputStreamReader isr = new InputStreamReader(System.in); BufferedReader br = new BufferedReader(isr); String s = br.readLine(); DecimalFormat df = new DecimalFormat(); Number n = df.parse(s); numberFromConsole = n.intValue(); } catch (ParseException ex) { Logger.getLogger(DoublyLinkedList.class.getName()).log(Level.SEVERE, null, ex); } catch (IOException ex) { Logger.getLogger(DoublyLinkedList.class.getName()).log(Level.SEVERE, null, ex); } return numberFromConsole; } and in my main method: public static void main(String[] args) { int i = 0; i = getRandomNumber(10, 10000); int p = chooseTheTypeOfSorting(); DoublyLinkedList list = new DoublyLinkedList(); for (int j = 0; j < i; j++) { list.add(j, getRandomNumber(10, 10000)); if (p == 0) { //do something.... } if (p == 1) { //do something..... } else { System.out.println("write the correct number "); chooseTheTypeOfSorting(); }

    Read the article

  • Eclipselink: Create objects from JOIN query

    - by Raven
    Hi, I have a SQL query SELECT * FROM Thing AS a JOIN Thing_Property AS b ON a.id=b.Thing_ID JOIN Property AS c ON b.properties_ID = c.id JOIN Item AS d ON c.item_ID = d.id ORDER BY a.name, d.name and I Eclipselink to create my object model with it. Here is the model: @SuppressWarnings("serial") @Entity public class Thing implements Serializable { @Id @GeneratedValue(strategy = GenerationType.TABLE) private int id; private String name; @OneToMany(cascade=CascadeType.ALL) @PrivateOwned private List<Property> properties = new ArrayList<Property>(); ... // getter and setter following here } public class Property implements Serializable { @Id @GeneratedValue(strategy = GenerationType.TABLE) private int id; @OneToOne private Item item; private String value; ... // getter and setter following here } public class Item implements Serializable { @Id @GeneratedValue(strategy = GenerationType.TABLE) private int id; private String name; .... // getter and setter following here } // Code end but I can not figure out, how to make Eclipselink create the model from that query. Can you help?

    Read the article

  • Navigating MainMenu with arrow keys or controller

    - by Phil Royer
    I'm attempting to make my menu navigable with the arrow keys or via the d-pad on a controller. So Far I've had no luck. The question is: Can someone walk me through how to make my current menu or any libgdx menu keyboard accessible? I'm a bit noobish with some stuff and I come from a Javascript background. Here's an example of what I'm trying to do: http://dl.dropboxusercontent.com/u/39448/webgl/qb/qb.html For a simple menu that you can just add a few buttons to and it run out of the box use this: http://www.sadafnoor.com/blog/how-to-create-simple-menu-in-libgdx/ Or you can use my code but I use a lot of custom styles. And here's an example of my code: import aurelienribon.tweenengine.Timeline; import aurelienribon.tweenengine.Tween; import aurelienribon.tweenengine.TweenManager; import com.badlogic.gdx.Game; import com.badlogic.gdx.Gdx; import com.badlogic.gdx.Screen; import com.badlogic.gdx.graphics.GL20; import com.badlogic.gdx.graphics.Texture; import com.badlogic.gdx.graphics.g2d.Sprite; import com.badlogic.gdx.graphics.g2d.SpriteBatch; import com.badlogic.gdx.graphics.g2d.TextureAtlas; import com.badlogic.gdx.math.Vector2; import com.badlogic.gdx.scenes.scene2d.Actor; import com.badlogic.gdx.scenes.scene2d.InputEvent; import com.badlogic.gdx.scenes.scene2d.InputListener; import com.badlogic.gdx.scenes.scene2d.Stage; import com.badlogic.gdx.scenes.scene2d.ui.Skin; import com.badlogic.gdx.scenes.scene2d.ui.Table; import com.badlogic.gdx.scenes.scene2d.ui.TextButton; import com.badlogic.gdx.scenes.scene2d.utils.Align; import com.badlogic.gdx.scenes.scene2d.utils.ClickListener; import com.project.game.tween.ActorAccessor; public class MainMenu implements Screen { private SpriteBatch batch; private Sprite menuBG; private Stage stage; private TextureAtlas atlas; private Skin skin; private Table table; private TweenManager tweenManager; @Override public void render(float delta) { Gdx.gl.glClearColor(0, 0, 0, 1); Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT); batch.begin(); menuBG.draw(batch); batch.end(); //table.debug(); stage.act(delta); stage.draw(); //Table.drawDebug(stage); tweenManager.update(delta); } @Override public void resize(int width, int height) { menuBG.setSize(width, height); stage.setViewport(width, height, false); table.invalidateHierarchy(); } @Override public void resume() { } @Override public void show() { stage = new Stage(); Gdx.input.setInputProcessor(stage); batch = new SpriteBatch(); atlas = new TextureAtlas("ui/atlas.pack"); skin = new Skin(Gdx.files.internal("ui/menuSkin.json"), atlas); table = new Table(skin); table.setBounds(0, 0, Gdx.graphics.getWidth(), Gdx.graphics.getHeight()); // Set Background Texture menuBackgroundTexture = new Texture("images/mainMenuBackground.png"); menuBG = new Sprite(menuBackgroundTexture); menuBG.setSize(Gdx.graphics.getWidth(), Gdx.graphics.getHeight()); // Create Main Menu Buttons // Button Play TextButton buttonPlay = new TextButton("START", skin, "inactive"); buttonPlay.addListener(new ClickListener() { @Override public void clicked(InputEvent event, float x, float y) { ((Game) Gdx.app.getApplicationListener()).setScreen(new LevelMenu()); } }); buttonPlay.addListener(new InputListener() { public boolean keyDown (InputEvent event, int keycode) { System.out.println("down"); return true; } }); buttonPlay.padBottom(12); buttonPlay.padLeft(20); buttonPlay.getLabel().setAlignment(Align.left); // Button EXTRAS TextButton buttonExtras = new TextButton("EXTRAS", skin, "inactive"); buttonExtras.addListener(new ClickListener() { @Override public void clicked(InputEvent event, float x, float y) { ((Game) Gdx.app.getApplicationListener()).setScreen(new ExtrasMenu()); } }); buttonExtras.padBottom(12); buttonExtras.padLeft(20); buttonExtras.getLabel().setAlignment(Align.left); // Button Credits TextButton buttonCredits = new TextButton("CREDITS", skin, "inactive"); buttonCredits.addListener(new ClickListener() { @Override public void clicked(InputEvent event, float x, float y) { ((Game) Gdx.app.getApplicationListener()).setScreen(new Credits()); } }); buttonCredits.padBottom(12); buttonCredits.padLeft(20); buttonCredits.getLabel().setAlignment(Align.left); // Button Settings TextButton buttonSettings = new TextButton("SETTINGS", skin, "inactive"); buttonSettings.addListener(new ClickListener() { @Override public void clicked(InputEvent event, float x, float y) { ((Game) Gdx.app.getApplicationListener()).setScreen(new Settings()); } }); buttonSettings.padBottom(12); buttonSettings.padLeft(20); buttonSettings.getLabel().setAlignment(Align.left); // Button Exit TextButton buttonExit = new TextButton("EXIT", skin, "inactive"); buttonExit.addListener(new ClickListener() { @Override public void clicked(InputEvent event, float x, float y) { Gdx.app.exit(); } }); buttonExit.padBottom(12); buttonExit.padLeft(20); buttonExit.getLabel().setAlignment(Align.left); // Adding Heading-Buttons to the cue table.add().width(190); table.add().width((table.getWidth() / 10) * 3); table.add().width((table.getWidth() / 10) * 5).height(140).spaceBottom(50); table.add().width(190).row(); table.add().width(190); table.add(buttonPlay).spaceBottom(20).width(460).height(110); table.add().row(); table.add().width(190); table.add(buttonExtras).spaceBottom(20).width(460).height(110); table.add().row(); table.add().width(190); table.add(buttonCredits).spaceBottom(20).width(460).height(110); table.add().row(); table.add().width(190); table.add(buttonSettings).spaceBottom(20).width(460).height(110); table.add().row(); table.add().width(190); table.add(buttonExit).width(460).height(110); table.add().row(); stage.addActor(table); // Animation Settings tweenManager = new TweenManager(); Tween.registerAccessor(Actor.class, new ActorAccessor()); // Heading and Buttons Fade In Timeline.createSequence().beginSequence() .push(Tween.set(buttonPlay, ActorAccessor.ALPHA).target(0)) .push(Tween.set(buttonExtras, ActorAccessor.ALPHA).target(0)) .push(Tween.set(buttonCredits, ActorAccessor.ALPHA).target(0)) .push(Tween.set(buttonSettings, ActorAccessor.ALPHA).target(0)) .push(Tween.set(buttonExit, ActorAccessor.ALPHA).target(0)) .push(Tween.to(buttonPlay, ActorAccessor.ALPHA, .5f).target(1)) .push(Tween.to(buttonExtras, ActorAccessor.ALPHA, .5f).target(1)) .push(Tween.to(buttonCredits, ActorAccessor.ALPHA, .5f).target(1)) .push(Tween.to(buttonSettings, ActorAccessor.ALPHA, .5f).target(1)) .push(Tween.to(buttonExit, ActorAccessor.ALPHA, .5f).target(1)) .end().start(tweenManager); tweenManager.update(Gdx.graphics.getDeltaTime()); } public static Vector2 getStageLocation(Actor actor) { return actor.localToStageCoordinates(new Vector2(0, 0)); } @Override public void dispose() { stage.dispose(); atlas.dispose(); skin.dispose(); menuBG.getTexture().dispose(); } @Override public void hide() { dispose(); } @Override public void pause() { } }

    Read the article

  • Catching constraint violations in JPA 2.0.

    - by Dennetik
    Consider the following entity class, used with, for example, EclipseLink 2.0.2 - where the link attribute is not the primary key, but unique nontheless. @Entity public class Profile { @Id private Long id; @Column(unique = true) private String link; // Some more attributes and getter and setter methods } When I insert records with a duplicate value for the link attribute, EclipseLink does not throw a EntityExistsException, but throws a DatabaseException, with the message explaining that the unique constraint was violated. This doesn't seem very usefull, as there would not be a simple, database independent, way to catch this exception. What would be the advised way to deal with this? A few things that I have considered are: Checking the error code on the DatabaseException - I fear that this error code, though, is the native error code for the database; Checking the existence of a Profile with the specific value for link beforehand - this obviously would result in an enormous amount of superfluous queries.

    Read the article

  • NetBeans config file

    - by Ockonal
    Hi guys, my NetBeans has ugly fonts in interface. I'm going to make antialiasing for it. In internet I saw that there is should be -J-Dswing.aatext=true -J-Dawt.useSystemAAFontSettings=on in netbeans_default_options. This file should be located in /etc/netbeans.conf. But there isn't this file. I have NetBeans 6.8. Help, please.

    Read the article

  • Recursion Question : Revision

    - by stan
    My slides say that: A recursive call should always be on a smaller data structure than the current one There must be a non recursive option if the data structure is too small You need a wrapper method to make the recursive method accessible Just reading this from the slides makes no sense, especially seeing as it was a topic from before christmas! Could anyone try and clear up what it means please? Thank you

    Read the article

  • How can a link within a WebView load another layout using javascript?

    - by huffmaster
    So I have 2 layout files (main.xml, featured.xml) and both each have a single WebView. When the application starts "main.xml" loads a html file into it's WebView. In this html file I have a link that calls javascript that runs code in the Activity that loaded the html. Once back in this Activity code though I try running setContentView(R.layout.featured) but it just bombs out on me. If I debug it just dies without any real error and if I run it the application just Force closes. Am I going about this correctly or should I be doing something differently? final private int MAIN = 1; final private int FEATURED = 2; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); webview = (WebView) findViewById(R.id.wvMain); webview.getSettings().setJavaScriptEnabled(true); webview.getSettings().setSupportZoom(false); webview.addJavascriptInterface(new EHJavaScriptInterface(), "eh"); webview.loadUrl("file:///android_asset/default.html"); } final class EHJavaScriptInterface { EHJavaScriptInterface() { } public void loadLayout(final String lo) { int i = Integer.parseInt(lo.trim()); switch (i) { /****** THIS IS WHERE I'M BOMBING OUT *********/ case FEATURED: setContentView(R.layout.featured);break; case MAIN: setContentView(R.layout.main);break; } } }

    Read the article

  • Overriding or overloading?

    - by atch
    Guys I know this question is silly but just to make sure: Having in my class method: boolean equal(Document d) { //do something } I'm overloading this method nor overriding right? I know that this or similiar question will be on upcoming egzam and would be stupid to not get points for such a simple mistake;

    Read the article

  • What does these FindBug messages show?

    - by Hans Klock
    Not every description from from http://findbugs.sourceforge.net/bugDescriptions.html is clear to me. Sure, I can study the implementation but if somebody is more experienced then me, some explanation and examples would be great. Do you have some examples for UI_INHERITANCE_UNSAFE_GETRESOURCE when this is getting a problem? In BX_UNBOXED_AND_COERCED_FOR_TERNARY_OPERATOR I don't see the problem either. If one type is "bigger" then the other, for example int and float, then the result is float. If its Integer and Float its the wrapper Float too. That's what I expect. Does the GC_UNRELATED_TYPES really help to find errors? Isn't it the job of the compiler to check, if--taking the given example--Foo can't go into a Collection<String>. Does HE_SIGNATURE_DECLARES_HASHING_OF_UNHASHABLE_CLASS mean something like bla(Foo f){hashtable.put(f);}, where ´Foo´ is not hashable? Does FingBugs "see" the subclasses too? NP_GUARANTEED_DEREF_ON_EXCEPTION_PATH is stronger "wrong" then NP_ALWAYS_NULL_EXCEPTION? Why two error cases and with NP_NULL_ON_SOME_PATH_EXCEPTION even one more? Sounds very similar to me. What is an example of SIO_SUPERFLUOUS_INSTANCEOF? Something like foo(String s){if (s intenceof String) .... This does a null check too, but this is not the test here... NN_NAKED_NOTIFY. I my opinion the description is not clear. A change of the state is not necessary. If I use new Object() to wait and notify on I don't change the object state. Or is state the lock-state? I don't get it. SP_SPIN_ON_FIELD. Can this really happen that a compiler will move this outside from a loop? This doesn't make sense to me because from outside a Thread can always change the values. And if the variable is volatile the JVM can't cache the value. So what's the meaning? That is the difference between STCAL_STATIC_CALENDAR_INSTANCE and STCAL_INVOKE_ON_STATIC_CALENDAR_INSTANCE or STCAL_INVOKE_ON_STATIC_DATE_FORMAT_INSTANCE/STCAL_STATIC_SIMPLE_DATE_FORMAT_INSTANCE? Why is XXXX.class in WL_USING_GETCLASS_RATHER_THAN_CLASS_LITERAL better then getClass()? A getClass() in a superclass called from the subclass will always return the Class object from the subclass which is good I think. What exactly does EQ_UNUSUAL do? It should check that the argument is of the same type of the class itself but it does't? Did you ever had problems with breaks? Is there real value with SF_SWITCH_FALLTHROUGH? Sounds to strong for me. No idea what TQ_EXPLICIT_UNKNOWN_SOURCE_VALUE_REACHES_ALWAYS_SINK and TQ_EXPLICIT_UNKNOWN_SOURCE_VALUE_REACHES_NEVER_SINK could be.

    Read the article

  • URI scheme is not "file"

    - by Ankur
    I get the exception: "URI scheme is not file" The url I am playing with is ... and it very much is a file http://local.wasp.uwa.edu.au/~pbourke/miscellaneous/domefisheye/ladybug/fish4.jpg What I am doing is trying to get the name of a file and then save that file (from another server) onto my computer/server from within a servlet. I have a String called "url", from thereon here is my code: url = Streams.asString(stream); //gets the URL from a form on a webpage System.out.println("This is the URL: "+url); URI fileUri = new URI(url); File fileFromUri = new File(fileUri); onlyFile = fileFromUri.getName(); URL fileUrl = new URL(url); InputStream imageStream = fileUrl.openStream(); String fileLoc2 = getServletContext().getRealPath("pics/"+onlyFile); File newFolder = new File(getServletContext().getRealPath("pics")); if(!newFolder.exists()){ newFolder.mkdir(); } IOUtils.copy(imageStream, new FileOutputStream("pics/"+onlyFile)); } The line causing the error is this one: File fileFromUri = new File(fileUri); I have added the rest of the code so you can see what I am trying to do.

    Read the article

  • JFrame is not acting as expected!

    - by DasWood
    This is my first time using a JFrame. I can't get the window to display the text areas I've nested inside the JFrame. I am trying to get the text field with my name in it to display above the tabulated results, which I have omitted the formatting for until I can get the JFrame to work. public void printResults(String[] names, int[] temp, int[][] scores, float[] averages, char[] letters){ JTextArea outarea= new JTextArea(5,20); JTextArea name = new JTextArea(5,20); Font font = new Font("Tahoma", Font.BOLD, 48); name.setFont(font); name.setText("Made By Durka Durka"); JFrame window = new JFrame(); window.getContentPane().add(name); window.getContentPane().add(outarea); window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); window.pack(); window.getContentPane().setVisible(true) String out = "twat"; outarea.setText(out); //JOptionPane.showMessageDialog(null,window); }

    Read the article

  • Why does this expression not work? JSF

    - by Nitesh Panchal
    Hello, I have a simple problem on .xhtml page. This expression is not working :- <a href="Photos.jsf?albumId=#{item.albumId}&blogId=#{PhotoAlbumsCommonBean.blogId}"> photos </a> I get this error :- Error Parsing /Common/PhotoAlbums.xhtml: Error Traced[line: 20] The reference to entity "blogId" must end with the ';' delimiter. & is causing some kind of error. Thanks in advance :)

    Read the article

  • Hibernate noob fetch join problem

    - by Bruce
    Hi all I have two classes, Test2 and Test3. Test2 has an attribute test3 that is an instance of Test3. In other words, I have a unidirectional OneToOne association, with test2 having a reference to test3. When I select Test2 from the db, I can see that a separate select is being made to get the details of the associated test3 class. This is the famous 1+N selects problem. To fix this to use a single select, I am trying to use the fetch=join annotation, which I understand to be @Fetch(FetchMode.JOIN) However, with fetch set to join, I still see separate selects. Here are the relevant portions of my setup.. hibernate.cfg.xml: <property name="max_fetch_depth">2</property> Test2: public class Test2 { @OneToOne (cascade=CascadeType.ALL , fetch=FetchType.EAGER) @JoinColumn (name="test3_id") @Fetch(FetchMode.JOIN) public Test3 getTest3() { return test3; } NB I set the FetchType to EAGER out of desperation, even though it defaults to EAGER anyway for OneToOne mappings, but it made no difference. Thanks for any help! Edit: I've pretty much given up on trying to use FetchMode.JOIN - can anyone confirm that they have got it to work ie produce a left outer join? In the docs I see that "Usually, the mapping document is not used to customize fetching. Instead, we keep the default behavior, and override it for a particular transaction, using left join fetch in HQL" If I do a left join fetch instead: query = session.createQuery("from Test2 t2 left join fetch t2.test3"); then I do indeed get the results I want - ie a left outer join in the query.

    Read the article

  • What would be the light way to render a JSP page without an App/Web Server

    - by kolrie
    First, some background: I will have to work on code for a JSP that will demand a lot of code fixing and testing. This JSP will receive a structure of given objects, and render it according to a couple of rules. What I would like to do, is to write a "Test Server" that would read some mock data out of a fixtures file, and mock those objects into a factory that would be used by the JSP in question. The target App Server is WebSphere and I would like to code, change, code in order to test appropriate HTML rendering. I have done something similar on the past, but the JSP part was just calling a method on a rendering object, so I created an Ad Hoc HTTP server that would read the fixture files, parse it and render HTML. All I had to do was run it inside RAD, change the HTML code and hit F5. So question pretty much goes down to: Is there any stand alone library or lightweight server (I thought of Jetty) that would take a JSP, and given the correct contexts (Request, Response, Session, etc.) render the proper HTML?

    Read the article

  • Return value changed after finally

    - by Nestor
    I have the following code: public bool ProcessData(String data) { try { result= CheckData(data); if (TextUtils.isEmpty(result)) { summary="Data is invalid"; return false; } ... finally { Period period = new Period(startTime, new LocalDateTime()); String duration = String.format("Duration: %s:%s", period.getMinutes(), period.getSeconds()); LogCat(duration); } return true; As I learned from this question, the finally block is executed after the return statement. So I modified my code according to that, and in the finally I inserted code that does not modify the output. Strangely, the code OUTSIDE the finally block does. My method always returns true. As suggested, it is not a good idea to have 2 return. What should I do?

    Read the article

  • What is the relation between ContentPane and JPanel?

    - by Roman
    I found one example in which buttons are added to panels (instances of JPanel) then panels are added to the the containers (instances generated by getContentPane) and then containers are, by the construction, included into the JFrame (the windows). I tried two things: I got rid of the containers. In more details, I added buttons to a panel (instance of JPanel) and then I added the panel to the windows (instance of JFrame). It worked fine. I got rid of the panels. In more details, I added buttons directly to the container and then I added the container to the window (instance of JFrame). So, I do not understand two things. Why do we have two competing mechanism to do the same things. What is the reason to use containers in combination with the panels (JPanel)? (For example, what for we include buttons in JPanels and then we include JPanels in the Containers). Can we include JPanel in JPanel? Can we include a container in container?

    Read the article

  • Is it possible to prevent out-of-order execution by using single volatile

    - by Yan Cheng CHEOK
    By referring article, it is using a pair of volatile to prevent out-of-order execution. I was wondering, is it possible to prevent it using single volatile? void fun_by_thread_1() { this.isNuclearFactory = true; this.factory = new NuclearFactory(); } void fun_by_thread_2() { Factory _factory = this.factory; if (this.isNuclearFactory) { // Do not operate nuclear factory!!! return; } // If out-of-order execution happens, _factory might // be NuclearFactory instance. _factory.operate(); } Factory factory = new FoodFactory(); volatile boolean isNuclearFactory = false; The reason I ask, is because I have a single guard flag (similar to isNuclearFactory flag), to guard against multiple variables (similar to many Factory). I do not wish to mark all the Factory as volatile. Or, shall I fall into the following solution? void fun_by_thread_1() { try { writer.lock(); this.isNuclearFactory = true; this.factory = new NuclearFactory(); } finally { writer.unlock(); } } void fun_by_thread_2() { try { reader.lock(); Factory _factory = this.factory; if (this.isNuclearFactory) { // Do not operate nuclear factory!!! return; } } finally { reader.unlock(); } _factory.operate(); } Factory factory = new FoodFactory(); boolean isNuclearFactory = false; P/S: I know instanceof. Factory is just an example to demonstrate of out-of-order problem.

    Read the article

  • How to get a Class literal from a generically specific Class

    - by h2g2java
    There are methods like these which require Class literals as argument. Collection<EmpInfo> emps = SomeSqlUtil.select( EmpInfo.class, "select * from emps"); or GWT.create(Razmataz.class); The problem presents itself when I need to supply generic specific classes like EmpInfo<String> Razmataz<Integer> The following would be wrong syntax Collection<EmpInfo<String>> emps = SomeSqlUtil.select( EmpInfo<String>.class, "select * from emps"); or GWT.create(Razmataz<Integer>.class); Because you cannot do syntax like Razmataz<Integer>.class So, how would I be able to squeeze a class literal out of EmpInfo<String> Razmataz<Integer> so that I could feed them as arguments to methods requiring Class literals? Further info Okay, I confess that I am asking this primarily for GWT. I have a pair of GWT RPC interface Razmataz. (FYI, GWT RPC interface has to be defined in server-client pairs). I plan to use the same interface pair for communicating whether it be String, Integer, Boolean, etc. GWT.create(Razmataz) for Razmataz<T> complains that, since I did not specify T, GWT compiler treated it as Object. Then GWT compiler would not accept Object class. It needs to be more specific than being an Object. So, it seems there is no way for me to tell GWT.create what T is because a Class literal is a runtime concept while generics is a compile time concept, Right?

    Read the article

  • GWT CSS Resource to find all classes

    - by Zoja
    What i want to do is: I have css file read from a file into a String. I would like to build some kind of css resource (CssResource ?) out of that string or file, and I'd like to be able to extract from it all classes and id selectors in some kind of collection which i could search. Does anybody know how to do that ?

    Read the article

< Previous Page | 799 800 801 802 803 804 805 806 807 808 809 810  | Next Page >