Search Results

Search found 41348 results on 1654 pages for 'java developer'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 944/1654 | < Previous Page | 940 941 942 943 944 945 946 947 948 949 950 951  | Next Page >

  • How can I get an error or a warning from a PreparedStatement?

    - by Geo
    I had an update like this: update table set col1=?,col2=?,col3=? where col4=?; and I filled it up like this: statement.setString(1,"some_value"); statement.setString(2,"some_value"); statement.setString(3,"some_value"); and I forgot to add a fourth value.I did a executeUpdate and of course nothing happened to the database. I spent about 1 hour debugging it, to see where it goes wrong. I then modified my code to print the SQLWarning object returned by the getWarnings method. It always returned null. I even modified the code to the buggy state it was, before I set the fourth parameter, and still no warning. Does anyone know how one can get an error/warning? If it matters, my Connection is set to autoCommit.

    Read the article

  • Wait between tasks with SingleThreadExecutor

    - by Lord.Quackstar
    I am trying to (simply) make a blocking thread queue, where when a task is submitted the method waits until its finished executing. The hard part though is the wait. Here's my 12:30 AM code that I think is overkill: public void sendMsg(final BotMessage msg) { try { Future task; synchronized(msgQueue) { task = msgQueue.submit(new Runnable() { public void run() { sendRawLine("PRIVMSG " + msg.channel + " :" + msg.message); } }); //Add a seperate wait so next runnable doesn't get executed yet but //above one unblocks msgQueue.submit(new Runnable() { public void run() { try { Thread.sleep(Controller.msgWait); } catch (InterruptedException e) { log.error("Wait to send message interupted", e); } } }); } //Block until done task.get(); } catch (ExecutionException e) { log.error("Couldn't schedule send message to be executed", e); } catch (InterruptedException e) { log.error("Wait to send message interupted", e); } } As you can see, there's alot of extra code there just to make it wait 1.7 seconds between tasks. Is there an easier and cleaner solution out there or is this it?

    Read the article

  • Servlet Session behavior and Session.invalidate

    - by EugeneP
    Suppose I have a web app with a servlet defined in web.xml. Then I deploy it on Tomcat. Then I open my browser and go to the link to this servlet, it is invoked. Then I close my browser window. How Session behaves ? How is it created, destroyed in this case? if this servlet is "detached" from all the web app, and gets parameters only using post & get, so it does not need Session at all, should one use Session.invalidate at the end of doGet(), doPost() ?

    Read the article

  • change a frame's attribute by pressing a button

    - by asavu
    Hi. Suppose we have a JFrame named frame1 with a String attribute named credentials set inittially to null. I have a jButton named button1 attached to the frame and I want to change the frame1 String credentials attribute by pressing button1. I need some piece of advice regarding the ActionListener code especially. Could you guys pls help me? Thank you.

    Read the article

  • What is an appropriate way to separate lifecycle events in the logging system?

    - by Hanno Fietz
    I have an application with many different parts, it runs on OSGi, so there's the bundle lifecycles, there's a number of message processors and plugin components that all can die, can be started and stopped, have their setup changed etc. I want a way to get a good picture of the current system status, what components are up, which have problems, how long they have been running for etc. I think that logging, especially in combination with custom appenders (I'm using log4j), is a good part of the solution and does help ad-hoc analysis as well as live monitoring. Normally, I would classify lifecycle events as INFO level, but what I really want is to have them separate from what else is going on in INFO. I could create my own level, LIFECYCLE. The lifecycle events happen in various different areas and on various levels in the application hierarchy, also they happen in the same areas as other events that I want to separate them from. I could introduce some common lifecycle management and use that to distinguish the events from others. For instance, all components that have a lifecycle could implement a particular interface and I log by its name. Are there good examples of how this is done elsewhere? What are considerations?

    Read the article

  • Can I have two names for the same variable?

    - by Roman
    The short version of the question: I do: x = y. Then I change x, and y is unchanged. What I want is to "bind" x and y in such a way that I change y whenever I change x. The extended version (with some details): I wrote a class ("first" class) which generates objects of another class ("second" class). In more details, every object of the second class has a name as a unique identifier. I call a static method of the first class with a name of the object from the second class. The first class checks if such an object was already generated (if it is present in the static HashMap of the first class). If it is already there, it is returned. If it is not yet there, it is created, added to the HashMap and returned. And then I have the following problem. At some stage of my program, I take an object with a specific name from the HashMap of the first class. I do something with this object (for example change values of some fields). But the object in the HashMap does not see these changes! So, in fact, I do not "take" an object from the HashMap, I "create a copy" of this object and this is what I would like to avoid.

    Read the article

  • How to define a class with variable properties?

    - by user1723326
    I'm making a database program. I want the user to be able to define their own columns, as many as they want. How would I then define each record in its class file?(Since the properties would be different user to user) EDIT: It's part of a school assignment-it's going to hold different scores and the likes for the teacher for different students they can add, but they will also be able to add a new assignment, test(a column) .

    Read the article

  • Must JDBC Resultsets and Statements be closed separately although the Connection is closed afterwards?

    - by Mulmoth
    It is said to be a good habit to close all JDBC resources after usage. But if I have the following code, is it necessary to close the Resultset and the Statement? Connection conn = null; PreparedStatement stmt = null; ResultSet rs = null; try { conn = // Retrieve connection stmt = conn.prepareStatement(// Some SQL); rs = stmt.executeQuery(); } catch { // Error Handling } finally { try { if (rs != null) rs.close(); } catch (Exception e) {}; try { if (stmt != null) stmt.close(); } catch (Exception e) {}; try { if (conn != null) conn.close(); } catch (Exception e) {}; } The question is if the closing of the connection does the job or if it leaves some resources in use.

    Read the article

  • Log4j Properties in a Custom Place

    - by Azder
    I'm using Apache Commons Logging and SLF4J with log4j, but I also want to use the log4j.properties in a custom place like conf/log4.properties. Here is the problem: If i use PropertyConfigurator.configure("conf/log4j.properties"); then my app is tied to log4j and defets the purpose of having ACL and SLF4J. What is the best way to configure it withouth the app ever knowing what the logging implementation is?

    Read the article

  • Swing: set JFrame content area size

    - by igul222
    I'm trying to make a JFrame with a usable content area of exactly 500x500. If I do this... public MyFrame() { super("Hello, world!"); setSize(500,500); } ... I get a window whose full size is 500x500, including the title bar, etc., where I really need a window whose size is something like 504x520 to account for the window border and titlebar. How can I achieve this?

    Read the article

  • graphing amplitude

    - by John
    I was wondering if someone could point me to a good tutorial or show me how to graph the amplitude from a bytearray. The audio format I am using is: ULAW 8000.0 Hz, 8 bit, mono, 1 bytes/frame.

    Read the article

  • Passing.getText() String to another class

    - by DanMc
    I'm currently working on a first year university project and I have a problem, although I doubt it's a very complicated one, but I've been searching and I just can't find a suitable answer to it. The problem concerns two classes. A gui class (class1) and another class (class2). I have a JTextField in class1 and am trying to pass through the .getText() value to class2 and store it in a String type variable. The current code I'm trying to achieve this with is the following: (Class1) private JTextField textField = new JTextField("Something"); ... public String getTextFieldString() { return textField.getText(); } (Class2) private c1 Class1 = new Class1(); private String s = new String(); ... s = c1.getTextFieldString(); I'm pretty new to coding, I've read that maybe I need to pass through an argument somewhere and I assume that's because textField is not static in itself, it changes when somebody enters a new value. (sorry for stating the obvious there.) Anyway, help is appreciated. Thanks a lot!

    Read the article

  • Get first character of each word and its position in a sentence/paragraph

    - by Radhika
    I am trying to create a map by taking the first character of each word and it's position in a sentence/paragraph. I am using regex pattern to achieve this. Regex is a costly operation. Are there are any ways to achieve this? Regex way: public static void getFirstChar(String paragraph) { Pattern pattern = Pattern.compile("(?<=\\b)[a-zA-Z]"); Map newMap = new HashMap(); Matcher fit = pattern.matcher(paragraph); while (fit.find()) { newMap.put((fit.group().toString().charAt(0)), fit.start()); } }

    Read the article

  • JTable cells not rendering shapes properly

    - by Andrew
    I'm trying to render my JTable cells with a subclassed JPanel and the cells should appear as coloured rectangles with a circle drawn on them. When the table displays initially everything looks OK but then when a dialog or something is displayed over the cells when it is removed the cells that have been covered do not rendered properly and the circles are broken up etc. I then have to move the scroll bar or extend the window to get them to redraw properly. The paintComponent method of the component I'm using to render the cells is below: protected void paintComponent(Graphics g) { setOpaque(true); super.paintComponent(g); Graphics2D g2d = (Graphics2D) g; GradientPaint gradientPaint = new GradientPaint(new Point2D.Double(0, 0), Color.WHITE, new Point2D.Double(0, getHeight()), paintRatingColour); g2d.setPaint(gradientPaint); g2d.fillRect(0, 0, getWidth(), getHeight()); g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); g2d.setRenderingHint(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY); Rectangle clipBounds = g2d.getClipBounds(); int x = new Double(clipBounds.getWidth()).intValue() - 15; int y = (new Double(clipBounds.getHeight()).intValue() / 2) - 6; if (level != null) { g2d.setColor(iconColour); g2d.drawOval(x, y, width, height); g2d.fillOval(x, y, width, height); } }

    Read the article

  • OGNL thread safety

    - by Dewfy
    I'm going to reuse OGNL library out of Struts2 scope. I have rather large set of formulas, that is why I would like to precompile all of them: Ognl.parseExpression(expressionString); But I'm not sure if precompiled expression can be used in multi-thread environment. Does anybody knows if it can be used?

    Read the article

  • Spring MVC: easiest way to see incoming requests

    - by flybywire
    I am debugging a Spring MVC (3.0) app, deployed on tomcat. I want to see in my console or log files all the incoming requests. Including 404s, both generated by my app or by spring because it didn't find an appropriate controller. I'd like to see something like this: GET /index.html GET /img/logo.png GET /js/a.js GET /style/b.css POST /ajax/dothis?blah=yes POST /ajax/dothat?foo=np GET /nextpage.html ... What is the easiest way to see that.

    Read the article

  • I have a feeling that adding fields marked with @Transient annotation to entity is very bug-prone. A

    - by Roman
    I have some philosophical feeling that adding to an entity fields which doesn't mapped to the DB is a wrong way of solving problems. But are there any concrete situations where using @Transient fields leads to implicit and hard fixing problems? For example, is it possible that adding/removing 2nd level cache will break our app when there are @Transient fields in our entities?

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 940 941 942 943 944 945 946 947 948 949 950 951  | Next Page >