Search Results

Search found 32961 results on 1319 pages for 'java'.

Page 908/1319 | < Previous Page | 904 905 906 907 908 909 910 911 912 913 914 915  | Next Page >

  • How to find out efficiently the auto-generated id for a new object when using JPA?

    - by webstarg
    Hello, I have an attribute which is annotated with @Id. The ID is going to be generated automatically when persisting the object. That means that the ID-value is not defined before I persist the object. After persisting it, it has an ID (in the database), but unfortunately the field still remains null as long as I don't reload it from the DB. is there any easy way to find out the generated id? Or better: To configure that it will be written into the field? Thanks in advance

    Read the article

  • JPanel superclass doesn't add the components of its subclasses..

    - by Acryl
    Well, I use a JFrame that adds two JPanels. Those JPanels are superclasses, because I find it easier to separate different areas of the GUI into different classes. But here's the problem: I add the (superclass) JPanel to the JFrame I set the layout of the superclass JPanel to new BorderLayout(); I add components in the subclasses, like this: JPanel panel = new JPanel(); panel.setLayout(new GridLayout(2,1)); panel.add(new JLabel("Label:"); panel.add(new JTextField(); add(panel, BorderLayout.NORTH); But it doesn't show. What do I do wrong? I've tried it without an additional JPanel in the subclasses, but it doesn't work either. I use jdk 1.6

    Read the article

  • How can I split abstract testcases in JUnit?

    - by Willi Schönborn
    I have an abstract testcase "AbstractATest" for an interface "A". It has several test methods (@Test) and one abstract method: protected abstract A unit(); which provides the unit under testing. No i have multiple implementations of "A", e.g. "DefaultA", "ConcurrentA", etc. My problem: The testcase is huge (~1500 loc) and it's growing. So i wanted to split it into multiple testcases. How can organize/structure this in Junit 4 without the need to have a concrete testcase for every implementation and abstract testcase. I want e.g. "AInitializeTest", "AExectueTest" and "AStopTest". Each being abstract and containing multiple tests. But for my concrete "ConcurrentA", i only want to have one concrete testcase "ConcurrentATest". I hope my "problem" is clear. EDIT Looks like my description was not that clear. Is it possible to pass a reference to a test? I know parameterized tests, but these require static methods, which is not applicable to my setup. Subclasses of an abstract testcase decide about the parameter.

    Read the article

  • need to clean malformed tags using regular expression

    - by Brian
    Looking to find the appropriate regular expression for the following conditions: I need to clean certain tags within free flowing text. For example, within the text I have two important tags: <2004:04:12 and . Unfortunately some of tags have missing "<" or "" delimiter. For example, some are as follows: 1) <2004:04:12 , I need this to be <2004:04:12> 2) 2004:04:12>, I need this to be <2004:04:12> 3) <John Doe , I need this to be <John Doe> I attempted to use the following for situation 1: String regex = "<\\d{4}-\\d{2}-\\d{2}\\w*{2}[^>]"; String output = content.replaceAll(regex,"$0>"); This did find all instances of "<2004:04:12" and the result was "<2004:04:12 ". However, I need to eliminate the space prior to the ending tag. Not sure this is the best way. Any suggestions. Thanks

    Read the article

  • How to write native SQL queries in Hibernate without hardcoding table names and fields?

    - by serg555
    Sometimes you have to write some of your queries in native SQL rather than hibernate HQL. Is there a nice way to avoid hardcoding table names and fields and get this data from existing mapping? For example instead of: String sql = "select user_name from tbl_user where user_id = :id"; something like: String sql = "select " + Hibernate.getFieldName("user.name") + " from " + Hibernate.getTableName(User.class) + " where " + Hibernate.getFieldName("user.id") + " = :id";

    Read the article

  • Matching Class arrays

    - by frinkz
    I'm writing a routine to invoke methods, found by a name and an array of parameter Class values Matching the Method by getName works, but when trying to match the given Class[] for parameters, and Method.getParameterTypes(), I'm having trouble. I assumed that this would work: Class[] searchParams = new Class[] { float.class, String.class }; Class[] methodParams = m.getParameterTypes(); if(methodParams == searchParams) { m.invoke(this, paramValues); } But apparantly not - m.invoke is never reached. I've checked, and methodParams gives the same classes as searchParams. The code below works, and picks the right method, but it seems like a very dirty way of doing things, I'm sure I'm missing something obvious. Class[] searchParams = new Class[] { float.class, String.class }; Class[] methodParams = m.getParameterTypes(); boolean isMatch = true; for(int i = 0; i < searchParams.length; i++) { if(!searchParams.getClass().equals(methodParams.getClass())) { isMatch = false; } } if(isMatch) { m.invoke(this, paramValues); }

    Read the article

  • replace capturing group

    - by Don
    Hi, If I have a regex with a capturing group, e.g. foo(_+f). If I match this against a string and want to replace the first capturing group in all matches with baz so that foo___f blah foo________f is converted to: foobaz blah foobaz There doesn't appear to be any easy way to do this using the standard libraries. If I use Matcher.replaceAll() this will replace all matches of the entire pattern and convert the string to baz blah baz Obviously I can just iterate through the matches, store the start and end index of each capturing group, then go back and replace them, but is there an easier way? Thanks, Don

    Read the article

  • Randomised objects are assigning themselves to more than one array location

    - by Thaddeus Aid
    this.size = 9; this.populationSize = 10; Random rand = new Random(); Integer[][] easy1 = new Integer[size][size]; easy1 = this.initializeEasy1(easy1); this.sudokuArray = new Sudoku[this.populationSize]; for (int i = 0; i < this.sudokuArray.length; i++){ long seed = rand.nextLong(); System.out.println("" + seed); this.sudokuArray[i] = new Sudoku(easy1, this.size, seed); } I am building an evolutionary sudoku solver and I am having a problem where the last Sudoku object is overwriting all the other objects in the array. Where in the code did I mess up? /edit here is the constructor of the class public Sudoku(Integer[][] givensGrid, int s, long seed){ this.size = s; this.givens = givensGrid; this.grid = this.givens.clone(); Random rand = new Random(seed); System.out.println("Random " + rand.nextInt()); // step though each row of the grid for (int i = 0; i < size; i++){ ArrayList<Integer> numbers = new ArrayList<Integer>(); numbers = this.makeNumbers(numbers); // step through each column to find the givens and remove from numbers for (int j = 0; j < size; j++){ if (this.grid[i][j] != 0){ numbers.remove(this.grid[i][j]); } } // go back through the row and assign the numbers randomly for (int j = 0; j < size; j++){ if (this.grid[i][j] == 0){ int r = rand.nextInt(numbers.size()); this.grid[i][j] = numbers.get(r); numbers.remove(r); } } } System.out.println("============="); System.out.println(this.toString()); }

    Read the article

  • JSplitPane overlaps JButtons in BorderLayout, but does not when layout is null

    - by thaweatherman
    So I'm having another issue..... I'm currently using a BorderLayout in my GUI so that when I resize my jframe, all of the internal components resize with it. I couldn't get any other layout to work with how I want the GUI to look while providing this resizing capability. At the top I have a JMenuBar, and below it I have a bunch of buttons. Below that I am supposed to have a JSplitPane, and it is there. However, the buttons seemed to be contained within the JSplitPane, which is not my intention. So when anything happens within the splitpane, the buttons disappear until I move my mouse over them again. When I set my layout to null everything works great except I lose the resizing capability, which is not good. Tried posting images but it wont let me since my rep isnt at 10 yet :( Any suggestions? I've tried putting the buttons into a JPanel then adding the jpanel but the splitpane overlaps with that. Same with a JToolBar. The order in which I add my items is: 1) the menu bar setJMenuBar(menuBar) 2) the buttons getContentPane().add(btnZoomIn) etc. 3) the split pane getContentPane().add(splitPane) then the rest of the things you see after that

    Read the article

  • "Overriding" instance variables in subtype: Possible risks?

    - by sebastiangeiger
    Say I had a class SuperClass and two subclasses SubClassA and SubClassB that inherit from SuperClass. abstract class SuperClass{ ... List someList; ... } class SubClassA extends SuperClass{ ... List<String> someList; ... } class SubClassB extends SuperClass{ ... List<Integer> someList; ... } That way it is convenient because I can get someList.size() in Superclass and have Typesafety in the Subclasses. The problem is that it does not "feel" right, can you think of potential hazards this apporach has that I am not aware of?

    Read the article

  • Compilation Error related

    - by aparna
    Given: 11. public static void test(String str) { 12. int check = 4; 13. if (check = str.length()) { 14. System.out.print(str.charAt(check -= 1) +", "); 15. } else { 16. System.out.print(str.charAt(0) + ", "); 17. } 18. } and the invocation: 21. test("four"); 22. test("tee"); 23. test("to"); What is the result? A. r, t, t, B. r, e, o, C. Compilation fails. D. An exception is thrown at runtime. Answer: C Can you explain why the compilation fails please?

    Read the article

  • servlet connection to DB

    - by underW
    Initially, after reading books on the subject, I firmly believed that the algorithm for working with a database from a servlet is as follows: create a connection - connect to the database - form a request - send the request to the database - get the query results - process them - close connection - OK. Now, with a better understanding of the practical side, I realized that nobody does it that way, and everything happens through a connection pool according to the following algorithm: initialize the servlet - create a connection pool - a request comes from a user - take a free connection from the pool - form a request - send the request to the database - get the query results - process them - return the connection back to the pool - ok. Now I have this problem: We have 100 users, they are divided into 10 groups, each group has it's own username and password to connect to the database. Moreover, each group may have different rights to the database. How am I supposed to use a connection pool in this situation? If I understand correctly, a pool is nothing more than just a group of similar connections with a single login and password. And here I have 10 pairs of username / password. It looks like I cannot use the pool in this situation. What should I do?

    Read the article

  • How do I change the build's SDK version in Xcode?

    - by Kavon Farvardin
    I'm using Xcode 2.5 on Mac 10.4.11 PPC. javac -version returns 1.5.x yet when I imported my source code and tried to build it in Xcode, I get errors all over because generics, annotations, and for-each loops are not supported in -source 1.3. I thought I found the setting to change the source version in Xcode in the above but it doesn't work. Any ideas?

    Read the article

  • javax.activation.DataSource size question

    - by folone
    How do I get the amount of physical memory, consumed by the DataSource (specifically — ByteArrayDataSource)? I use ByteArrayDataSource (byte[] bytes, String type) constructor, where I get bytes like this: String str = "test"; byte[] bytes = str.getBytes(); Would that be str.length() in bytes? Any other ideas?

    Read the article

  • How to set Camera View as background with views over it?

    - by Android Student
    So, I'm trying to make the background to one of my apps look "futuristic." I thought of an idea to make the screen look almost transparent yet have views over it. So, it would look something like this: I'm thinking that I can use the camera to capture the background of the phone (without taking a picture, just having the real time view in the background) and then, if possible, place a semi-transparent slightly blurred ImageView over that. Finally, on top of that I can place the other views including the ImageButtons. So, my question is how would I go about doing this? I have searched but haven't found anything relevant. It must be possible; its just how to do it? I don't expect you to give me all the code as an answer, just if you have any ideas that can help or links or code that can point me in the right direction, it would be greatly appreciated! Thanks!

    Read the article

  • Confusion with a while statement evaluating if a number is triangular

    - by Darkkurama
    I've been having troubles trying to figure out how to solve a function. I've been assigned the development of a little programme which tells if a number is "triangular" (a number is triangular when the addition of certain consecutive numbers in the [1,n] interval is n. Following the definition, the number 10 is triangular, because in the [1,10] interval, 1+2+3+4=10). I've coded this so far: class TriangularNumber{ boolean numTriangular(int n) { boolean triangular = false; int i = n; while(n>=0 && triangular){ //UE06 is a class which contains the function "f0", which makes the addition of all the numbers in a determined interval UE06 p = new UE06(); if ((p.f0(1, i))==n) triangular = true; else i=i-1; } return triangular; } boolean testTriangular = numTriangular(10) == true && numTriangular(7) == false && numTriangular(6) == true; public static void main(String[] args){ TriangularNumber p = new TriangularNumber(); System.out.println("testTriangular = " + p.testTriangular); } } According to those boolean tests I made, the function is wrong. As I see the function, it goes like this: I state that the input number in the initial state isn't triangular (triangular=false) and i=n (determining the interval [1,i] where the function is going to be evaluated While n is greater or equals 0 and the number isn't triangular, the loop starts The loop goes like this: if the addition of all the numbers in the [1,i] interval is n, the number is triangular, causing the loop to end. If that statement is false, i goes from i to (i-1), starting the loop again with that particular interval, and so on till the addition is n. I can't spot the error in my "algorithm", any advice? Thanks!

    Read the article

  • Socket Programming : Inputstream Stuck in loop - read() always return 0

    - by Atom Skaa ska Hic
    Server side code public static boolean sendFile() { int start = Integer.parseInt(startAndEnd[0]) - 1; int end = Integer.parseInt(startAndEnd[1]) - 1; int size = (end - start) + 1; try { bos = new BufferedOutputStream(initSocket.getOutputStream()); bos.write(byteArr,start,size); bos.flush(); bos.close(); initSocket.close(); System.out.println("Send file to : " + initSocket); } catch (IOException e) { System.out.println(e.getLocalizedMessage()); disconnected(); return false; } return true; } Client Side public boolean receiveFile() { int current = 0; try { int bytesRead = bis.read(byteArr,0,byteArr.length); System.out.println("Receive file from : " + client); current = bytesRead; do { bytesRead = bis.read(byteArr, current, (byteArr.length-current)); if(bytesRead >= 0) current += bytesRead; } while(bytesRead != -1); bis.close(); bos.write(byteArr, 0 , current); bos.flush(); bos.close(); } catch (IOException e) { System.out.println(e.getLocalizedMessage()); disconnected(); return false; } return true; } Client side is multithreading,server side not use multithreading. I just paste some code that made problem if you want see all code please tell me. After I debug the code, I found that if I set max thread to any and then the first thread always stuck in this loop. That bis.read(....) always return 0. Although, server had close stream and it not get out of the loop. I don't know why ... But another threads are work correctly. do { bytesRead = bis.read(byteArr, current, (byteArr.length-current)); if(bytesRead >= 0) current += bytesRead; } while(bytesRead != -1);

    Read the article

  • How do scroll the contents to bottom by default in JTextPane?

    - by Nitesh Panchal
    Hello, I have JTextPane on my window and i have JTextField. When i press enter enter in JTextField, the text gets added in JTextPane. Everything works fine and scrollbar too appears on its own. But, it doesn't appear properly. It automatically scrolls to the beginning of the content in JTextPane. How do i keep the scrollbar to the end of JTextPane? Please let me know if my question is unclear. Thanks in advance :)

    Read the article

  • Ignoring all line feeds in a FreeMarker template

    - by Will
    I'm trying out FreeMarker, not for a web application but to generate text within a desktop application. I'd like to get the text without any linefeeds, however it always appends a linefeed. For example, this would produce "blah blah\n" <#if docType=1> blah blah <#if docType=2> more blah <#/if> Any ideas? Bunching it all into one line works, but is horrible. Thanks.

    Read the article

  • How to see "anti if" movement and its gaol?

    - by Vijay Shanker
    I have a developer for last 3 years, have been using if-else or if-else if statements a lot in my programing habit. And today, I found This link. One obvious sample i put here public void doSomthing(String target, String object){ //validate requests if(target != null && target.trim().length() < 1){ //invalid request; } //further logic } Now, I have seen this sort of check all over the places, libraries. So, I wanted to have a discussion about the worthiness of such a movement. Please let me know your views.

    Read the article

  • How do I reload servlet classes without restarting my web application?

    - by Ramon
    I want to reload just my web layer classes without reloading my service layer classes (which take longer to initialize and change less frequently). There are no references from my service layer into the web layer and I can create a whole new instance of the web layer without problems. I can conceive of a solution involving complicated class-loader tricks to isolate the web layer in its own class-loader and I think this is probably the only way to do this so what I'm asking is, is there a library out there which does this? I know about JavaRebel - I don't need that much power and I'm really looking for a more lightweight free solution.

    Read the article

< Previous Page | 904 905 906 907 908 909 910 911 912 913 914 915  | Next Page >