I have this code :
public static void main(String[] args) throws InterruptedException {
Object obj = new Object();
obj.wait();
obj.notify();
}
please I didn't understand why it throws java.lang.IllegalMonitorStateException??
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user1703945
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4by reading the documentation the Truth will be revealed to you. – Marko Topolnik Nov 18 '13 at 22:05
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@MarkoTopolnik Ah, found the reason. – nanofarad Nov 18 '13 at 22:08
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when I add this : `synchronized (Thread.currentThread()) { obj.wait(); obj.notify(); }` it give me the same exception. – user1703945 Nov 18 '13 at 22:09
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1Not a valid question to ask here , it should have been asked so many times – Jayasagar Nov 18 '13 at 22:10
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of course it gives you the same exception, as documented – Marko Topolnik Nov 18 '13 at 22:13
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Sorry, my duplicate question was _not_ the right one. This is better: http://stackoverflow.com/a/1537400/179850 – Gray Nov 18 '13 at 22:15
1 Answers
3
In order to wait on or notify on an object, you must be in a synchronized block locking on the object.
The following code will work (run but not do anything as there are no threads to synchronize):
public static void main(String[] args) throws InterruptedException {
Object obj = new Object();
synchronized(obj){
obj.wait();
obj.notify();
}
}
