Search Results

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

Page 306/1421 | < Previous Page | 302 303 304 305 306 307 308 309 310 311 312 313  | Next Page >

  • Blackberry (Java) - Can't get KeyListener to work

    - by paullb
    I am trying to get the KeyListener working for Blackberry, but none of the Dialogs pop up indicating that a key has been pressed (see code below, each action has a dialog popup in them). Any ideas on what i might be doing wrong? public class CityInfo extends UiApplication implements KeyListener { static CityInfo application; public static void main(String[] args) { //create a new instance of the application //and start the application on the event thread application.enterEventDispatcher(); } public CityInfo() { //display a new screen application = new CityInfo(); pushScreen(new WorkflowDisplayScreen()); this.addKeyListener(this); } public boolean keyChar(char arg0, int arg1, int arg2) { // TODO Auto-generated method stub Dialog.alert("key pressed : " + arg0); return true; } public boolean keyDown(int keycode, int time) { // TODO Auto-generated method stub Dialog.alert("keyDown : " + keycode); return false; } public boolean keyRepeat(int keycode, int time) { // TODO Auto-generated method stub Dialog.alert("keyRepeat : " + keycode); return false; } public boolean keyStatus(int keycode, int time) { // TODO Auto-generated method stub Dialog.alert("keyStatus : " + keycode); return false; } public boolean keyUp(int keycode, int time) { Dialog.alert("keyUp : " + keycode); // TODO Auto-generated method stub return false; } } I also tried implementing keyChar on the MainScreen class but that did not yield any results either.

    Read the article

  • Gracefully avoiding NullPointerException in Java

    - by Yuval A
    Consider this line: if (object.getAttribute("someAttr").equals("true")) { // .... Obviously this line is a potential bug, the attribute might be null and we will get a NullPointerException. So we need to refactor it to one of two choices: First option: if ("true".equals(object.getAttribute("someAttr"))) { // .... Second option: String attr = object.getAttribute("someAttr"); if (attr != null) { if (attr.equals("true")) { // .... The first option is awkward to read but more concise, while the second one is clear in intent, but verbose. Which option do you prefer in terms of readability?

    Read the article

  • Java: Make a method abstract for each extending class

    - by Martijn Courteaux
    Hi, Is there any keyword or design pattern for doing this? public abstract class Root { public abstract void foo(); } public abstract class SubClass extends Root { public void foo() { // Do something } } public class SubberClass extends SubClass { // Here is it not necessary to override foo() // So is there a way to make this necessary? // A way to obligate the developer make again the override } Thanks

    Read the article

  • How to extract byte-array from one xml and store it in another in Java

    - by grobartn
    So I am using DocumentBuilderFactory and DocumentBuilder to parse an xml. So it is DOM parser. But what I am trying to do is extract byte-array data (its an image encoded in base64) Store it in one object and later in code write it out to another xml encoded in base64. What is the best way to store this in btw. Store it as string? or as ByteArray? How can I extract byte array data in best way and write it out. I am not experienced with this so wanted to get opinion from the group. UPDATE: I am given XML I do not have control of incoming XML that comes in binary64 encoded < byte-array > ... base64 encoded image ... < /byte-array > Using parser I have I need to store this node and question is should that be byte or string and then writing it out to another node in new xml. again in base64 encoding. thanks

    Read the article

  • Java BoxLayout alignment issue

    - by ManInMoon
    Can anyone help me. Why is the Label "Current" NOT left aligned in Panel/Frame? public static void main(String[] args) { JFrame TFrame = new JFrame("Test DisplayLayout"); TFrame.setResizable(true); TFrame.setSize(new Dimension(900, 840)); TFrame.setLocationRelativeTo(null); TFrame.setTitle("DisplayLayout"); TFrame.setVisible(true); JPanel P = DisplayLayout2(); P.setVisible(true); P.setOpaque(true); P.setLayout(new BoxLayout(P, BoxLayout.Y_AXIS)); TFrame.add(P); TFrame.revalidate(); TFrame.repaint(); } public static JPanel DisplayLayout2() { JPanel Panel=new JPanel(); Panel.setVisible(true); Panel.setOpaque(true); Panel.setLayout(new BoxLayout(Panel, BoxLayout.Y_AXIS)); Panel.setAlignmentX(Component.LEFT_ALIGNMENT); JLabel lab = new JLabel("Current"); lab.setHorizontalAlignment(SwingConstants.LEFT); lab.setForeground(Color.WHITE); lab.setBackground(Color.PINK); lab.setOpaque(true); Panel.add(lab,Component.LEFT_ALIGNMENT); JPanel posPanel = new JPanel(); JScrollPane scrollPane = new JScrollPane(posPanel,JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,JScrollPane.HORIZONTAL_SCROLLBAR_NEVER); scrollPane.setPreferredSize(new Dimension(290, 200)); scrollPane.setOpaque(true); posPanel.setBackground(Color.YELLOW); posPanel.setPreferredSize(new Dimension(290, 200)); posPanel.setLayout(new BoxLayout(posPanel, BoxLayout.Y_AXIS)); posPanel.setAlignmentX(Component.LEFT_ALIGNMENT); Panel.add(scrollPane); return Panel; }

    Read the article

  • Enumeration classes in Java

    - by Crystal
    I have one class that declares an enumeration type as: public enum HOME_LOAN_TERMS {FIFTEEN_YEAR, THIRTY_YEAR}; Is this type usable in another class? I'm basically trying to complete a homework assignment where we have two types of loans, and one loanManager class. When I try to use the HOME_LOAN_TERMS.THIRTY_YEAR in my loanManager class that does not extend or implement the loan class, I get an error saying it 'cannot find symbol HOME_LOAN_TERMS.' So I did not know if my loanManager class needed to implement the two different loan classes. Thanks.

    Read the article

  • Blackberry (Java) - Drawing graphics on top of rendered text/buttons etc

    - by paullb
    Based off the one of the demos I have the following code. Currently what displays in the simulator is just hte contents of the paint function, however the ObjectChoiceField is still selectable if one happens to click in the right location. I would like both the text contents and the paint function contents to appear. Is this possible? public CityInfoScreen() { //invoke the MainScreen constructor super(); //add a screen title LabelField title = new LabelField("City Information Kiosk", LabelField.ELLIPSIS | LabelField.USE_ALL_WIDTH); setTitle(title); //add a text label add(new RichTextField("Major U.S. Cities")); //add a drop-down list with three choices: //Los Angeles, Chicago, or New York //... String choices[] = {"Los Angeles","Chicago","New York"}; choiceField = new ObjectChoiceField("select a city", choices); add(choiceField); Manager man = this.getMainManager(); } ... public void paint(Graphics g){ super.paint(g); // g.drawRect(0,left,500,500+left); g.setGlobalAlpha(0); g.drawRect(100-left,100-top,200,200); String text = new Integer(left).toString(); String text2 = new Integer(top).toString(); g.drawText(text + " " + text2,120-left,120-top); }

    Read the article

  • java and mysql geting shortest path from to two points

    - by shaharnakash
    hi i have a mysql database that hold id ,name , oneid , twoid , size 1 1 1 2 4 2 2 1 3 1 3 3 2 1 74 4 4 2 4 2 5 5 2 5 12 6 6 4 2 12 7 7 4 6 74 8 8 4 7 12 9 9 3 5 32 10 10 3 8 22 11 11 5 3 66 12 12 5 6 76 13 13 5 9 33 14 14 6 10 11 15 15 6 7 21 16 16 8 3 12 17 17 8 9 10 18 18 9 8 2 19 19 9 10 72 20 20 10 6 31 21 21 10 7 7 22 22 10 9 18 23 23 7 6 8 i want to do Dijkstra algorithm but i cant get the details right if i got the contents to class Conn id ,name , oneid , twoid , size how do i find the path from oneid 1 to twoid 7 and believe me i triad many Dijkstra algorithms so please dont give me only reference

    Read the article

  • java servlet: generate zip file from BLOBs

    - by Zack
    I'm trying to zip a large number of pdf files (stored as BLOBs in the DB) and then return the zip as an attachment to the user. What's the best way to do this without running into memory issues? Another note: I actually need to merge some PDFs prior to adding them to the ZipOutputStream. Therefore, a couple PDFs will need to be stored in memory at a time. I assume it would be best to then store them as temporary files on the server before zipping them all?

    Read the article

  • java number exceeds long.max_value - how to detect?

    - by jurchiks
    I'm having problems detecting if a sum/multiplication of two numbers exceeds the maximum value of a long integer. Example code: long a = 2 * Long.MAX_VALUE; System.out.println("long.max * smth > long.max... or is it? a=" + a); This gives me -2, while I would expect it to throw a NumberFormatException... Is there a simple way of making this work? Because I have some code that does multiplications in nested IF blocks or additions in a loop and I would hate to add more IFs to each IF or inside the loop. Edit: oh well, it seems that this answer from another question is the most appropriate for what I need: http://stackoverflow.com/a/9057367/540394 I don't want to do boxing/unboxing as it adds unnecassary overhead, and this way is very short, which is a huge plus to me. I'll just write two short functions to do these checks and return the min or max long. Edit2: here's the function for limiting a long to its min/max value according to the answer I linked to above: /** * @param a : one of the two numbers added/multiplied * @param b : the other of the two numbers * @param c : the result of the addition/multiplication * @return the minimum or maximum value of a long integer if addition/multiplication of a and b is less than Long.MIN_VALUE or more than Long.MAX_VALUE */ public static long limitLong(long a, long b, long c) { return (((a > 0) && (b > 0) && (c <= 0)) ? Long.MAX_VALUE : (((a < 0) && (b < 0) && (c >= 0)) ? Long.MIN_VALUE : c)); } Tell me if you think this is wrong.

    Read the article

  • How to copy .java sources to Ant javac destFolder

    - by Ittai
    Hi, I know how to use Ant to copy files and folders but what I'm interested in is if, and how, I can have the javac task copy the same sources it's compiling to the output directory. Basically, it's very similar to the option to include your sources in the jar task. Thanks in advance, Ittai

    Read the article

  • Java convert JSONObject to URL parameter

    - by Alex Ivasyuv
    What is the elegant way to convert JSONObject to URL parameters. For example, JSONObject: {stat: {123456: {x: 1, y: 2}, 123457: {z: 5, y: 2}}}} this should be like: stat[123456][x]=1&stat[123456][y]=2&stat[123457][z]=5&stat[123457][y]=2 of course with escaped symbols, and of course JSON object could be more complicated.. Maybe there already exist some mechanisms for that? Thanks,

    Read the article

  • I have a problem with the following Java code

    - by Sanjeev
    public class b { public static void main(String[] args) { byte b = 1; long l = 127; // b = b + l; // 1 if I try this then it does not compile b += l; // 2 if I try this then it does compile System.out.println(b); } } I am using this code but I have problem: I don't understand why b=b+l; is not compiling but if I write b+=l; then it compiles and runs. Please explain why this happens.

    Read the article

  • HELP easy java program [closed]

    - by gentrit
    type first integer , type second integer, , program repeatedly outputs the second value of the number of times indicated by the first value. Example use inputs 4 and 2, 222 2 displayed. another example user inputs 3 and 8 , 88 8 displayed

    Read the article

  • Have threads run indefinitely in a java application

    - by TP
    I am trying to program a game in which I have a Table class and each person sitting at the table is a separate thread. The game involves the people passing tokens around and then stopping when the party chime sounds. how do i program the run() method so that once I start the person threads, they do not die and are alive until the end of the game One solution that I tried was having a while (true) {} loop in the run() method but that increases my CPU utilization to around 60-70 percent. Is there a better method?

    Read the article

  • base-n series generator for a given number in java,,

    - by Senthil
    I want to create a program for generating the series for the given base-n. , for example if my input is 2,then series shuould be, 00,01,10,11,etc.,(binary) if my input is 10,then series shuould be,1,2,3,4,5,etc.,(decimal) is there any general mechanism to find these numbers so that I can program for base-n.,

    Read the article

  • Incorrect Date in Java

    - by Polaris
    I use next code to print current time Calendar cal = Calendar.getInstance(); System.out.println(cal.getTime()); I have Windows XP sp3 istalled. Current time in system tray is 14:30. But this code return 13:30 Why returned time is wrong?

    Read the article

  • Better way to write this Java code?

    - by Macha
    public void handleParsedCommand(String[] commandArr) { if(commandArr[0].equalsIgnoreCase("message")) { int target = Integer.parseInt(commandArr[1]); String message = commandArr[2]; MachatServer.sendMessage(target, this.conId, message); } else if(commandArr[0].equalsIgnoreCase("quit")) { // Tell the server to disconnect us. MachatServer.disconnect(conId); } else if(commandArr[0].equalsIgnoreCase("confirmconnect")) { // Blah blah and so on for another 10 types of command } else { try { out.write("Unknown: " + commandArr[0] + "\n"); } catch (IOException e) { System.out.println("Failed output warning of unknown command."); } } } I have this part of my server code for handling the types of messages. Each message contains the type in commandArr[0] and the parameters in the rest of commandArr[]. However, this current code, while working seems very unelegant. Is there a better way to handle it? (To the best of my knowledge, String values can't be used in switch statements, and even then, a switch statement would only be a small improvement.

    Read the article

  • Duplicates in a sorted java array

    - by Max Frazier
    I have to write a method that takes an array of ints that is already sorted in numerical order then remove all the duplicate numbers and return an array of just the numbers that have no duplicates. That array must then be printed out so I can't have any null pointer exceptions. The method has to be in O(n) time, can't use vectors or hashes. This is what I have so far but it only has the first couple numbers in order without duplicates and then just puts the duplicates in the back of the array. I can't create a temporary array because it gives me null pointer exceptions. public static int[] noDups(int[] myArray) { int j = 0; for (int i = 1; i < myArray.length; i++) { if (myArray[i] != myArray[j]) { j++; myArray[j] = myArray[i]; } } return myArray; }

    Read the article

  • Get annotations of return type in Java

    - by Apropos
    I'm using Spring MVC and am using aspects to advise my controllers. I'm running into one issue: controllers that return a value annotated with the @ResponseBody type. How are you able to find the annotations applied to the return type? @Around("myPointcut()") private Object checkAnnotations(ProceedingJoinPoint pjp) throws Throwable { Object result = pjp.proceed(); Method method = ((MethodSignature)pjp.getSignature()).getMethod(); System.out.println("Checking return type annotations."); for(Annotation annotation : method.getReturnType().getAnnotations()){ System.out.println(annotation.toString()); } System.out.println("Checking annotations on returned object."); for(Annotation annotation : result.getClass().getAnnotations()){ System.out.println(annotation.toString()); } return result; } Unfortunately, neither of these methods seem to have the desired effect. I can retrieve annotations on the type of object being returned, but not the ones being added at return time.

    Read the article

  • In Java, does return trump finally?

    - by jonny five
    If I have a try/catch block with returns inside it, will the finally block be called? For example: try { something(); return success; } catch (Exception e) { return failure; } finally { System.out.println "i don't know if this will get printed out." } I know I can just type this in an see what happens (which is what I'm about to do, actually) but when I googled for answers nothing came up, so I figured I'd throw this up as a question. Thanks!

    Read the article

  • How would you code an efficient Circular Buffer in Java or C#

    - by Cheeso
    I want a simple class that implements a fixed-size circular buffer. It should be efficient, easy on the eyes, generically typed. EDIT: It need not be MT-capable, for now. I can always add a lock later, it won't be high-concurrency in any case. Methods should be: .Add and I guess .List, where I retrieve all the entries. On second thought, Retrieval I think should be done via an indexer. At any moment I will want to be able to retrieve any element in the buffer by index. But keep in mind that from one moment to the next Element[n] may be different, as the Circular buffer fills up and rolls over. This isn't a stack, it's a circular buffer. Regarding "overflow": I would expect internally there would be an array holding the items, and over time the head and tail of the buffer will rotate around that fixed array. But that should be invisible from the user. There should be no externally-detectable "overflow" event or behavior. This is not a school assignment - it is most commonly going to be used for a MRU cache or a fixed-size transaction or event log.

    Read the article

  • Java simple data format british time

    - by DD
    Hi, I am using simple date format to allow users to specify which time zone they are sending data in: DateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss,z"); This works fine: e.g. df.parse("2009-05-16 11:07:41,GMT"); However, if someone is always sending time in London time (i.e. taking into account daylight savings), what would be the approriate time zone String to add? e.g. this doesnt work: df.parse("2009-05-16 11:07:41,Europe/London"); Thanks.

    Read the article

< Previous Page | 302 303 304 305 306 307 308 309 310 311 312 313  | Next Page >