Most voted "java" questions
Use this tag when the question refers to some resource, information, or problem relating exclusively to the Java programming language. Java is a class-based, statically typed, reflective, and execution environment (JRE) language. Java programs are compiled to bytecode and run on a virtual machine (JVM), allowing a "write Once, run Anywhere" philosophy (WORA).
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answers155
viewsTreeview - Jtree (Netbeans) Adding a description to a selected node
I am doing a simple treeview in Netbeans and would like to know how to add a description to a selected node by means of a button that has a function that will associate to a lable. the code for the…
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answers124
viewsDifferences xml lines Android (Eclipse)
Guys, in the course I do Android he works on the platform Eclipse(Old version) and I in the latest version, when the teacher uses the command: android.id in it’s all right, but if I type this line…
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answer130
viewsWhen using recursion method returns 0
I have the following code: public int lerInt() { String entrada = ""; int saida = 0; try { entrada = input.readLine(); } catch (IOException e) { System.out.println("Falha critica."); } try { saida =…
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answer4105
viewsCalculator using Java Socket
I’m doing a job at the college and I took some information from the Internet, the professor asked a client to submit 2 values and a basic operation, the server should take this and return the total.…
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answers977
viewsHow to use JSON response?
After a lot of trying I arrived at this result of JQUERY AJAX, but I still could not use the JSON data, they do not work, how should I do ? give a Help ! thank you The JSON response ta at the end…
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answer1330
viewsInheritance with jpa
Hello, I have a class called Usuario that is abstract and I have the class UsuarioComum and Administrador which they inherit from Usuario, I am using JPA annotations to generate the automatic…
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answer527
viewsjava.lang.Nullpointerexception in this code
This gives java.lang.Nullpointerexception error in these two classes. import javax.swing.JButton; import javax.swing.JPanel; import javax.swing.JTextArea; import javax.swing.JTextField; public class…
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answers2363
viewsClose all open jframes when opening a new one
How can I close all jframes opened in my project when I run an action that opens another jframe? I have a login system and when necessary, I invoke another frame to define a password. After setting…
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answers842
viewsHow to add a JAR library to a Java project without IDE?
Save. I’m having trouble adding the Jfreechart library to my Java project (using Windows 8). I’ve unpacked Jfreechart, but I don’t know what to do from there. Since I’m an old school programmer and…
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answers2377
viewsWhat is this error javax.servlet.Servletexception: getOutputStream()?
I am generating a report, the moment I click to issue and it displays this error. Exception: javax.servlet.ServletException: getOutputStream() has already been called for this response at…
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answer73
viewsHow to decode an object via URL?
I have the object URL and I needed to encode and then de-perform, how do I do that? The URL is from a server that displays a Java object encoded and serialized.
javaasked 9 years, 4 months ago daniel12345smith 2,120 -
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answer348
viewsCheckbox checked/unchecked does not obey instructions
To Activity is started with the layout activity_home and the CheckBox unchecked. When I touch CheckBox, the layout becomes the activity_home_avancado, however the Checkbox remains unmarked. At the…
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answers267
viewsLock F5 key in the application
Good afternoon, I am developing a Java Web application, and found that after performing a registration and typing F5 the information gets duplicated, only the ID that does not duplicate because it…
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answer486
viewsDownload via FTP with Javascript
I would like to know how I can be putting on my page the user option to download via FTP. I do not want the user to enter the information for access to FTP and also that he does not see the FTP data…
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answers437
viewsSelect if the collection contains a particular object with Hibernate Criteria
I’m trying to make a query that would be something like the method contains of interface Collection java. I have a class GrupoProdutos and want to select the groups if your Collection, calling for…
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answers33
viewsWhat is the possible cost of using blocks for exception treatment in too ?
As exceptions are interruptions caused most of the time by the operating system, I wonder if there is any cost of memory (stack/heap) since, existing exception treatment the program continues to run…
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answer1150
viewsCreate graphical interface using Miglayout
I need to create this graphical interface: The last code I tried was this: (but the settings are not correct) frame.setLayout(new MigLayout("wrap","[grow]","[grow][]")); panelInfo.setLayout(new…
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answers711
viewsHow to persist the String of an Enumerator in the Database?
I have the following Enumerator: public enum ETipoCasa{ Propria, Alugada, Financiada, Cedida; } And I’m trying to persist in the database the string of this enumerator as an example: Casa casa = new…
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answer402
viewsWhat is the best way to develop a video player from scratch?
Well, I would like to know what topics, articles books finally references would help me in the task of developing a video player from scratch as the average classic player for example?
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answers54
viewsUpdate Main via an Intentservice
I have an application that works together with GCM (Google Cloud Messages), which consults the server and when there is news sends a notification to the user. I need to update my Mainactivity…
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answer1966
viewsWhy is my app not compatible with some devices on Google play?
I posted an app on google play, but unfortunately it’s not available for some of my devices. I am very confused, because in the development with Eclipse, I used the same devices for testing and they…
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answer628
viewsHow to use variables in a location outside the scope where they were created?
I have the following code: public class TracoActivity extends Activity { protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState);…
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answers55
viewsProblems when closing RAD screen splash (v7.5)
I’m having an unusual problem (who doesn’t?), My Launcher/splash screen opens, but it keeps this state even after I choose the desktop and after RAD loads the project. It only closes when I stop all…
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answer573
viewsTabs on Android
I’m trying to implement a simple code just to show two tabs on Android and later add a content dividing into two activities, one to show examples with IF and the other with SWITCH. I created the…
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answer49
viewsPhp script in java ? runs in the background?
I have a question. I have a script which takes about 40 seconds to execute. I’m thinking so if I have run on android, the user if not willing to wait the 40 seconds, what happens he closes in the…
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answers202
viewsHow to optimally read a list of Arraylist dependencies?
I’m in four classes, each class has one ArrayList, where the last element depends on another ArrayList: Example Genêro->Artists->Albuns->Music To read the songs I’m doing as follows. for…
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answer72
viewsJavacv applet does not display video in the browser, only on the desktop
I am developing a web application that connects to a security camera via Javacv. The applet I developed runs normally on the desktop, but when I try to run in the browser, although it does not give…
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answers814
viewsChecking Time in java
Given a list of times ex.: String[] times = {"11:00", "12:00", "13:00"}; I want to take my current time and compare with the list which is the next hour, eg.: current time is 11:30, taken from the…
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answer104
viewsClient side deleted object instance and sends to the server
I wonder if anyone has ever been through this problem and how did you solve it. I am using JSP and Spring Data JPA. I delete records from the middle of a form that’s a detail using Javascript,…
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answer151
viewsVersioning . jar in Java with Netbeans
I wish that mine .jar had a version number and release date inside it, so I could inform it on the about screen for example. So far no mystery, but the point is that every build in Netbeans I wanted…
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answer733
viewsHow to "delete" an image from the screen
In this code I would like to delete the image I put before and not one on top of the other. Graphics g = getGraphics(); Graphics bbg = backBuffer.getGraphics(); bbg.drawImage(fundo.getImage(), 0, 0,…
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answer2863
viewsJava how to do a native query and return to a DTO list
I am using Spring Hibernate and am trying to make a native query with Join back to a DTO list. I tried using @Query(value="", nativeQuery=true) with a List but it returns the serialized attributes.…
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answers952
viewsEnum as Hibernate Parameter Namedquery
Is there any way to pass as a parameter in a NamedQuery the value of Enum. public enum TipoConta{ CREDITO("Cartao de Credito"), DEBITO("Cartao de Debito"); private final String descricao;…
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answer139
viewsManipulate onPostExecute from another Activity
I have both classes below: Dataload.java public class DataLoad extends Activity { SQLiteDatabase mDatabase; Session session; public static String jsonString = ""; @Override protected void…
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answer103
viewsHow to pass to column of a Dynamicreports the contents of a compound object. Datasource is a list of this object
I’m making a report using Dynamicreports For this I am passing a list to be used as Datasource List<VisaoViagemQuadroMensal> linhas = new ArrayList<VisaoViagemQuadroMensal>(); where :…
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answer713
viewsHow to set a new (external) source for a Jtextpane
I have a JTextPane and I want to define a new source (found on the internet) for it. I saw several tutorials, but none of them could define the source, I would like to make it as simple as possible.…
javaasked 9 years, 3 months ago Lucas Caresia 2,663 -
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answer799
viewsError sending image to Imgur, how to resolve?
I’m trying to send an image to Imgur but it’s giving error, I can’t remember how to get the image. I’m using this code: public static String getImgurContent() throws Exception { URL url; url = new…
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answers198
viewsListview infinity on android
I have an app that consumes a web service, only I have a generic call that searches all users and this taking a long time because I have several records, I want to do so the user goes down the…
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answers634
viewsChange in audit in Java+Spring+Oracle application
I am tasked with changing an audit implementation in an application in which I work. The requirement of the audit is to know the history of changes, and execution of certain tasks by a given user.…
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answer1026
viewsCentering text on a Jtextarea or Jtextpane
In this image the text is not centered, it is far above the JTextArea: And I would also like the text to begin in the middle of JTextArea and was adjusting as I was writing. What method can I use to…
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answer310
viewsJava - Chat async
I want to implement a chat in java, which works asynchronously, and I wanted to know the best architecture to do this. I managed to make a public chat using sockets(Netty), but I got to the…
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answer1430
viewsHow to add element inside an arrayList that is inside another Arraylist that in turn is inside a Hashmap?
The question is: I have the Classes Student, Discipline, Grade, Class. I need to add a double value in an Arraylist that is in an object of the Discipline class, but the Discipline class is inside…
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answer124
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answer364
viewsInterceptor at Spring MVC
I made an Interceptor so that every time the system had a message to display trigger a javascript with the message. public class MessagesInterceptor extends HandlerInterceptorAdapter { public static…
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answer1383
viewsLoad values from an already saved Selectitem into a database on the screen
I have a problem to load the selected value in <f:selectItem> by the user When render gets that way: <option value="320">Coordenador Desenvolvimento</option> I wanted the attribute…
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answer177
viewsIdentify an Object property in Java+JPA and change it
I’m creating a class to get a database record and write to another database. I’m using JPA and bumped into a problem. I’m doing a generic insertion and I have to clean up the ID of the table to be…
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answers308
viewsHow do I access an Arraylist of Fragments after a screen rotation?
I was trying to programmatically add to my Activity a list of Fragments that implement some Cardviews. These Cardviews have some Textviews that I would like to set from my Activity, and in fact, it…
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answer6363
viewsReturn vector of integers in java
I’m trying to read an array of integers and return the number of ones and the number of zeros, but it always returns at least a zero number, even without me having entered it. Debugging the code,…
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answer1260
viewsHow to get a POST parameter in REST application
I started a Rest application and have a java class createPost POST @Path("/post/") @Produces(MediaType.APPLICATION_JSON) public static String createPost(@FormParam("loopID") String loopID) throws…
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answer164
viewsManipulating two lists of a Drag and Drop component in different Managedbeans
I am using the Datatable Drag And Drop component. Contextualizing is as follows: I got a rap sheet based on footsteps. Where in the first step I enter the information of an Edict X, what is…