Search Results

Search found 84599 results on 3384 pages for 'java util set'.

Page 319/3384 | < Previous Page | 315 316 317 318 319 320 321 322 323 324 325 326  | Next Page >

  • How to end a thread in java?

    - by beagleguy
    hi all, I have 2 pools of threads ioThreads = (ThreadPoolExecutor)Executors.newCachedThreadPool(); cpuThreads = (ThreadPoolExecutor)Executors.newFixedThreadPool(numCpus); I have a simple web crawler that I want to create an iothread, pass it a url, it will then fetch the url and pass the contents over to a cpuThread to be processed and the ioThread will then fetch another url, etc... At some point the IO thread will not have any new pages to crawl and I want to update my database that this session is complete. How can I best tell when the threads are all done processing and the program can be ended?

    Read the article

  • Why doesn't Java Map extends Collection?

    - by polygenelubricants
    I was surprised by the fact that Map<?,?> is not a Collection<?>. I thought it'd make a LOT of sense if it was declared as such: public interface Map<K,V> extends Collection<Map.Entry<K,V>> After all, a Map<K,V> is a collection of Map.Entry<K,V>, isn't it? So is there a good reason why it's not implemented as such?

    Read the article

  • Real life Java Swing Project

    - by santiagobasulto
    Hi everybody! I've been working with swing for the last 2 years, but i'm still not satisfy with my own work. The apps are "fast" enough, but the development isn't enough "clean". Can you recommend me any real world project, book, or something similar that shows me how a real world swing app work. May be a framework, something structured, etc. For example, i'm thinking i may code a "window manager" that has all the window of the app in an unified resource, may be cached, etc. I think all those good ideas must be implemented already. Thanks!

    Read the article

  • Java JTextArea Bold

    - by ikurtz
    This is an exploratory query. I am wondering if the following is possible with JTextArea? Can I alter the text to bold (append text) and then back to normal and will it only display the bold text in bold and the rest as normal? Also can the contents of JTextArea be saved as a RTF document? Thank you.

    Read the article

  • java multiple operations depending on the type of the object passed

    - by mixm
    assuming i create a method which is passed an object, and that method would perform an action depending on the object passed. how should i identify the object? i thought of using the class name to identify the object, but may be impractical since i could easily change the class name of objects, and generate headaches during future development. am i right?

    Read the article

  • Validating IPv4 string in Java

    - by Mat Banik
    Bellow method is validating if string is correct IPv4 address it returns true if it is valid. Any improvements in regex and elegance would be very appreciated: public static boolean validIP(String ip) { if (ip == null || ip.isEmpty()) return false; ip = ip.trim(); if ((ip.length() < 8) & (ip.length() > 15)) return false; try { Pattern pattern = Pattern.compile("^(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$"); Matcher matcher = pattern.matcher(ip); return matcher.matches(); } catch (PatternSyntaxException ex) { return false; } }

    Read the article

  • Java Timer not working

    - by Jacob
    I have an Image named worldImageToUse and I have a Timer that is supposed to toggle worldImageToUse between two images every 1 second. But it does not seem to work. Help Please? public void startWorldImageFlash() { worldImageFlashTimer = new Timer(); TimerTask task = new TimerTask() { @Override public void run() { if(worldImageToUse == worldImage) setWorldImageBW(); if(worldImageToUse == worldImageBW) setWorldImageColor(); } }; worldImageFlashTimer.scheduleAtFixedRate(task, 0, 1000); } public void stopWorldImageFlash() { worldImageFlashTimer.cancel(); setWorldImageColor(); }

    Read the article

  • Java side scrolling game on android

    - by hanesjw
    I'm trying to make an easy side scrolling game just to learn the ropes of game programming on android. I came up with a solution of how to make it but I don't really think it is the most elegant solution. I wanted to get some different ideas on how to implement my game, as I really have no other solution right now. Here is a quick explanation of how it works.. I basically have blocks or objects fall from the top of the screen. The blocks are defined from a pre-defined string I create using a custom 'map-editor'. I create all the blocks at compile time, position them on or off the screen and simply increment their coordinates with each iteration of the gameloop. It is actually done a little bit better then that, but that gives a short easy explanation on the basic idea. I heard from a few people that instead of incrementing each block position, have the blocks stay there and simply change the viewable area. That makes sense, but I have no idea how to do it. Can anyone share some ideas or links on how I can implement something like this? I know my current solution isn't the greatest. Thanks!

    Read the article

  • socket problem in java

    - by stefan89
    I have two classes X and Y, like this: class X implements Serializable { int val1; Y val2; } class Y implements Serializable { int val; } I want to transmit an object of type X from a client to server but i can't because the class X has a field of type Y. I replace the field of type Y with a field of type X in class X and it works.

    Read the article

  • Dynamic, reflective SignalHandler in Java

    - by pilcrow
    How do I install signal handling logic iff sun.misc.Signal is available? Background First generation of my code looked something like this: class MyApp { public static void main(String[] args) { ... Signal.handle(term_sig, new SignalHandler() { public void handle(Signal sig) { ... } }); ... } } I believe I understand how to reflectively test for and use signal handlers -- Class.forName("sun.misc.Signal"), reflectively call Signal.handle, and so forth. My impulse was simply to instantiate another anonymous inner class with the dynamically obtained SignalHandler class, but I think that's just wishful syntax.

    Read the article

  • Extracting user-friendly exception details in Java

    - by Jon
    I've got a J2EE web application that I'm working on and when an exception occurs, I'd like to get some basic details about the exception and log it. The message that I'm logging should be pretty basic, something that might mean something to the people running the web server(s). Would using e.getMessage() be the best thing to log? Thanks.

    Read the article

  • Java String object creation

    - by Ajay
    Hi, 1) What is difference in thers two statements: String s1 = "abc"; and String s1 = new String("abc") 2) as i am not using new in first statement, how string object will be created Thanks

    Read the article

  • Java - Thread safety of ArrayList constructors

    - by andy boot
    I am looking at this piece of code. This constructor delegates to the native method "System.arraycopy" Is it Thread safe? And by that I mean can it ever throw a ConcurrentModificationException? public Collection<Object> getConnections(Collection<Object> someCollection) { return new ArrayList<Object>(someCollection); } Does it make any difference if the collection being copied is ThreadSafe eg a CopyOnWriteArrayList? public Collection<Object> getConnections(CopyOnWriteArrayList<Object> someCollection) { return new ArrayList<Object>(someCollection); }

    Read the article

  • Assigning int to byte in java?

    - by user303218
    int val =233; byte b = (byte)val; System.out.println(b); I have a simple case, like one integer with some value & i want to convert that value & place in the byte type for output. But in this case negative value is coming? How to successfully place the int value to byte type.

    Read the article

  • java increase xmx dynamically at runtime

    - by Tomer
    Hi, I have a jvm server in my machine, now I want to have 2 apservers of mine sitting in same machine, however I want the standby one to have a really low amount of memory allocated with xmx because its passive, one the main server (active) goes down I want to allocate more memory to my passive server which is already up without restarting it (I have have them both having too much xmx - note they would consume memory at startup and I cant allow possibility of outOfMemory). So I want passive - low xmx once active goes down I want my passive to receive much more xmx. is there a way for me to achieve that. Thanks

    Read the article

  • Java Days & Bookings

    - by sys_debug
    Ok this is an extension of a question I asked about earlier yet this is the next step that is unclear to me. Everything else will be ready and this part is driving me mad! some members provided great help and I already made progress with that info, but this is just another obstacle. I am creating a booking object (as was suggested) that will have a start date and end date. each booking will also have a number of seats associated with it (that I require to reserve). The total available number of seats any given day 46 (as the total capacity of the hall is 46 seats). so in assumption that I have a booking to be made in the system, and start date is 1st jan and end date is 10th jan. The question is how can I check the remaining seats in all those days between the range to see if requested number could be hosted or not? and then when the second booking is made, it will have to see that the days in this range already have less than 46 and decrement further if possible to host the reservation. one of the members, and I appreciate his effort, gladly contributed a method to compare if this booking is after or before the existing bookings. The code provided is here: public boolean overlapsWithExisting(Booking booking) { final Date early = booking.getStart(); final Date late = booking.getEnd(); for(Booking existing : existingBookings) { if(!(early.isAfter(existing.getEnd() || late.isBefore(existing.getStart())) return true; } return false; } I just want to know how to associate 46 with each day and keep record of days that are decremented by bookings. Thanks and reallllllly appreciated :D

    Read the article

  • Why does Java return a date in GMT-4.5 when choosing Co-ordinated Universal Time time zone in Window

    - by Simon Nickerson
    We have seen a strange issue on some Windows XP machines involving the "Co-ordinated Universal Time" time zone. Not all Windows XP machines seem to have it, but on those that do, the following simple Java program public class TimeTest { public static void main(String[] args) { System.out.println(java.util.TimeZone.getDefault()); System.out.println(new java.util.Date()); } } on JDK 1.6.0_06 prints: sun.util.calendar.ZoneInfo[id="America/Caracas",offset=-16200000,dstSavings=0,useDaylight=false,transitions=5,lastRule=null] Fri Nov 13 05:34:14 VET 2009 (i.e. 4 and a half hours behind GMT). I should add that I am based in London, and have never been to South America. :-) My questions are: Where does Java get this time zone from? I thought Co-ordinated Universal Time was supposed to be the new name for GMT. Why do some Windows machines have this time zone but not others?

    Read the article

< Previous Page | 315 316 317 318 319 320 321 322 323 324 325 326  | Next Page >