Search Results

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

Page 455/1421 | < Previous Page | 451 452 453 454 455 456 457 458 459 460 461 462  | Next Page >

  • Java long task - Did it stop writing to file?

    - by rockit
    I am writing a lot of data to a file, and while keeping my eye on the file it eventually stopped growing in size. Essentially my task is getting information from a database, and printing out all non-unique values in column A. Since there are many rows to the database table, and the database table is across my network, this is taking days to complete. Thus I'm concerned that since the file isn't growing, that it isn't actually writing to the file anymore. Which is odd, I have no "catch"'s in my code, so if there was a problem writing to file, wouldn't it have thrown an error?! Should I let the task complete (estimate 2-3 days from today), or is there something else that I don't know going on here making my application not write to the file?! my algorithm goes something like this Declare file Create new file Open file for writing get database connection get resultset from database for each row in the resultset - write column "A" to file - if row# % 100000 then write to screen "completed " + row# + " rows" when no more rows exist close file write to screen - "completed"

    Read the article

  • How to map oracle timestamp to appropriate java type in hibernate?

    - by jschoen
    I am new to hibernate and I am stumped. In my database I have tables that have a columns of TIMESTAMP(6). I am using Netbeans 6.5.1 and when I generate the hibernate.reveng.xml, hbm.xml files, and pojo files it sets the columns to be of type Serializable. This is not what I expected, nor what I want them to be. I found this post on the hibernate forums saying to place: in the hibernate.reveng.xml file. In Netbeans you are not able to generate the mappings from this file (it creates a new one every time) and it does not seem to have the ability to re-generate them from the file either (at least according to this it is slated to be available in version 7). So I am trying to figure out what to do. I am more inclined to believe I am doing something wrong since I am new to this, and it seems like it would be a common problem for others. So what am I doing wrong? If I am not doing anything wrong, how do I work around this? I am using Netbeans 6.5, Oracle 10G, and I believe Hibernate 3 (it came with my netbeans). Edit: Meant to say I found this stackoverflow question, but it is really a different problem.

    Read the article

  • Using an interface as a constructor parameter in Java?

    - by aperson
    How would I be able to accomplish the following: public class testClass implements Interface { public testClass(Interface[] args) { } } So that I could declare Interface testObject = new testClass(new class1(4), new class2(5)); Where class1 and class2 are also classes that implement Interface. Also, once I accomplish this, how would I be able to refer to each individual parameter taken in to be used in testClass? Thanks :)

    Read the article

  • Java- Copy file to either new file or existing file.

    - by jared
    Hi- I would like to write a function copy(File f1, File f2) f1 is always a file. f2 is either a file or a directory. If f2 is a directory I would like to copy f1 to this directory (the file name should stay the same). If f2 is a file I would like to copy the contents of f1 to the end of the file f2. So for example if F2 has the contents: 2222222222222 And F1 has the contents 1111111111111 And I do copy(f1,f2) then f2 should become 2222222222222 1111111111111 Thanks!

    Read the article

  • How to test whether a char is NOT in a string? (java, junit)

    - by JB
    As title says, im having trouble with my junit tests passing for checking if a character is not in a string and how to check if an empty string doesnt have a character. here is the method i have: public static boolean isThere(String s, char value){ for(int x = 0; x <= s.length(); x++){ if(s.charAt(x) == value){ return true; } else if(s.length() == 0){ return false; } } return false; And here is the junit test: public void testIsThere() { { String sVal = "Jeff George"; boolean hasA = StringMethods.isThere(sVal,'e'); assertTrue(hasA); boolean hasE = StringMethods.isThere(sVal, 'o'); assertTrue(hasE); boolean notIn = StringMethods.isThere(sVal,'b'); assertTrue(notIn); } { String sVal = ""; boolean nothingIn = StringMethods.isThere(sVal,'a'); assertFalse(nothingIn); boolean notIn = StringMethods.isThere(sVal,'b'); assertFalse(notIn); } } Thank you very much, appreciated

    Read the article

  • How do I keep JTextFields in a Java Swing BoxLayout from expanding?

    - by Matthew
    I have a JPanel that looks something like this: JPanel panel = new JPanel(); panel.setLayout(new BoxLayout(panel, BoxLayout.Y_AXIS)); ... panel.add (jTextField1); panel.add (Box.createVerticalStrut(10)); panel.add (jButton1); panel.add (Box.createVerticalStrut(30)); panel.add (jTextField2); panel.add (Box.createVerticalStrut(10)); panel.add (jButton2); ... //etc. My problem is that the JTextFields become huge vertically. I want them to only be high enough for a single line, since that is all that the user can type in them. The buttons are fine (they don't expand vertically). Is there any way to keep the JTextFields from expanding? I'm pretty new to Swing, so let me know if I'm doing everything horribly wrong.

    Read the article

  • How to sort data in a table data structure in Java?

    - by rgksugan
    I need to sort data based on the third column of the table data structure. I tried based on the answers for the following question. But my sorting does not work. Please help me in this. Here goes my code. Object[] data = new Object[y]; rst.beforeFirst(); while (rst.next()) { int p_id = Integer.parseInt(rst.getString(1)); String sw2 = "select sum(quantity) from tbl_order_detail where product_id=" + p_id; rst1 = stmt1.executeQuery(sw2); rst1.next(); String sw3 = "select max(order_date) from tbl_order where tbl_order.`Order_ID` in (select tbl_order_detail.`Order_ID` from tbl_order_detail where product_id=" + p_id + ")"; rst2 = stmt2.executeQuery(sw3); rst2.next(); data[i] = new Object[]{new String(rst.getString(2)), new String(rst.getString(3)), new Integer(rst1.getString(1)), new String(rst2.getString(1))}; i++; } ColumnComparator cc = new ColumnComparator(2); Arrays.sort(data, cc); if (i == 0) { table.addCell(""); table.addCell(""); table.addCell(""); table.addCell(""); } else { for (int j = 0; j < y; j++) { Object[] theRow = (Object[]) data[j]; table.addCell((String) theRow[0]); table.addCell((String) theRow[1]); table.addCell((String) theRow[2]); table.addCell((String) theRow[3]); }

    Read the article

  • How to generate a random BigInteger value in Java?

    - by Bill the Lizard
    I need to generate arbitrarily large random integers in the range 0 (inclusive) to n (exclusive). My initial thought was to call nextDouble and multiply by n, but once n gets to be larger than 253, the results would no longer be uniformly distributed. BigInteger has the following constructor available: public BigInteger(int numBits, Random rnd) Constructs a randomly generated BigInteger, uniformly distributed over the range 0 to (2numBits - 1), inclusive. How can this be used to get a random value in the range 0 - n, where n is not a power of 2?

    Read the article

  • Java, How to Instance HttpCookie from a String, any convenient ways?

    - by user435657
    Hi all, I have got a cookie string from HTTP response header like the following line: name=value; path=/; domain=.g.cn; expire=... I can parse the above line to key-value pairs, and, also it's easy to set the name and value to HttpCookie instance as this pair comes the first. But how to set the other pairs since I don't know which set-method corresponds to the name of the next name-value pair. Traverse all possible keys a cookie may contian and call the matched set-method, like below snippet? if (key.equalsIgnoreCase("path")) cookie.setPath(value); else if (key.equalsIgnoreCase("domain")) cookie.setDomain(value); That's foolish, any convenient ways? Thanks in advance.

    Read the article

  • Analysing objects generated by a Java application in between GCs.

    - by elec
    Is there a tool which could be used to analyse the objects being created between two separate garbage collection run (= number of objects created and their type) ? Heapdumps dont really work here as they perform a GC when they're invoked (or at least that's what I observed everytime so far), and I want to see which objects are collected by the GC, not which objects are left after the GC run, if that makes sense. ...or is it possible somehow to inspect the nature and size of objects being collected by the garbage collector ?

    Read the article

  • Java: How to check if a date Object equals yesterday?

    - by tzippy
    Right now I am using this code Calendar cal = Calendar.getInstance(); SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd"); cal.set(cal.get(Calendar.YEAR), cal.get(Calendar.MONTH), cal.get(Calendar.DATE) - 1, 12, 0, 0); //Sets Calendar to "yeserday, 12am" if(sdf.format(getDateFromLine(line)).equals(sdf.format(cal.getTime()))) //getDateFromLine() returns a Date Object that is always at 12pm {...CODE There's got to be a smoother way to check if the date returned by getdateFromLine() is yesterday's date. Only the date matters, not the time. That's why I used SimpleDateFormat. Thanks for your help in advance!

    Read the article

  • Java Graphics not displaying on successive function calls, why?

    - by primehunter326
    Hi, I'm making a visualization for a BST implementation (I posted another question about it the other day). I've created a GUI which displays the viewing area and buttons. I've added code to the BST implementation to recursively traverse the tree, the function takes in coordinates along with the Graphics object which are initially passed in by the main GUI class. My idea was that I'd just have this function re-draw the tree after every update (add, delete, etc...), drawing a rectangle over everything first to "refresh" the viewing area. This also means I could alter the BST implementation (i.e by adding a balance operation) and it wouldn't affect the visualization. The issue I'm having is that the draw function only works the first time it is called, after that it doesn't display anything. I guess I don't fully understand how the Graphics object works since it doesn't behave the way I'd expect it to when getting passed/called from different functions. I know the getGraphics function has something to do with it. Relevant code: private void draw(){ Graphics g = vPanel.getGraphics(); tree.drawTree(g,ORIGIN,ORIGIN); } vPanel is what I'm drawing on private void drawTree(Graphics g, BinaryNode<AnyType> n, int x, int y){ if( n != null ){ drawTree(g, n.left, x-10,y+10 ); if(n.selected){ g.setColor(Color.blue); } else{ g.setColor(Color.gray); } g.fillOval(x,y,20,20); g.setColor(Color.black); g.drawString(n.element.toString(),x,y); drawTree(g,n.right, x+10,y+10); } } It is passed the root node when it is called by the public function. Do I have to have: Graphics g = vPanel.getGraphics(); ...within the drawTree function? This doesn't make sense!! Thanks for your help.

    Read the article

  • What can you do and not do with java annotations?

    - by swampsjohn
    The typical use-case is for simple things like @Override, but clearly you can do a lot more with them. If you push the limits of them, you get things like Project Lombok, though my understanding is that that's a huge abuse of annotations. What exactly can you do? What sort of things can you do at compile-time and run-time with annotations? What can you not do?

    Read the article

< Previous Page | 451 452 453 454 455 456 457 458 459 460 461 462  | Next Page >