Threads Section Index | Page 2

The Thread API allows Threads to be created which are at the mercy of their user threads. This is accomplished simply by passing true to the setDaemon() method and invoking the method off an insta...more

The setUncaughtExceptionHandler() method of Thread, introduced in JDK 5.0, allows you to configure this behavior by letting you attach an implementation of Thread.UncaughtExceptionHandler. The int...more

[I know a HashMap object is not synchronized if not done explicitly, so in a case where you have to write and read data in a hashmap from different threads you need to synchronize it (or use anoth...more

[I have a thread which is sleeping for a long period of time.Another object has the object of this sleeping thread. In some event , the second object wants to wake up the sleeping thread before i...more

Any ordering that you are observing is not mandated by the spec. It is therefore subject to change and should not be relied on (even using a multi-processor machine instead of a single processor o...more

Is there an example of a chat server (aka Threaded Virtual Meeting Place) ?

Here's how to print the trace in a string: Exception ex = new Exception("something went wrong"); StringWriter sw = new StringWriter(); ex.printStackTrace(new PrintWriter(sw)); String stacktrace =...more

Double-checked locking (DCL) is an idiom recommended by a number of Java books and articles as a way to reduce synchronization overhead when performing lazy initialization. The DCL idiom was des...more

http://java.sun.com/docs/hotspot/threads/threads.html

Every object instance in Java has a little piece of data hanging off of it called a "monitor lock." This is similar to a semaphore. When you use the synchronized keyword, the current thread at...more

I can do it in the following way class RemindTask extends TimerTask { public void run() { System.out.println("run task"); } } Timer timer = new Timer(); ti...more

Sure it is, since it is a Vector which is thread-safe.

My servlet reads the contents of a text file which I access using a File object. What issues are involved when this file is read concurrently by several different threads? Do I have to synchronize...more

[Short answer: you can't stop the thread, but you can close the socket, which causes accept to return. -Alex] Hope that I've understood you properly. So I assume, that you've got something like: ...more

Yes. See Is there some way to implement multi-tasking in Java? and also look at the docs for java.lang.Runtime.exec(). See also What is the difference between multithreading and multitasking (et ...more