What is IllegalMonitorStateException in Java?

What is IllegalMonitorStateException in Java?

Class IllegalMonitorStateException Thrown to indicate that a thread has attempted to wait on an object’s monitor or to notify other threads waiting on an object’s monitor without owning the specified monitor.

Which exception is thrown by Wait method?

IllegalMonitorStateException
The IllegalMonitorStateException is related to multithreading programming in Java. If we have a monitor we want to synchronize on, this exception is thrown to indicate that a thread tried to wait or to notify other threads waiting on that monitor, without owning it.

How do you use wait and notify in Java?

There are two ways of notifying waiting threads.

  1. 4.1. notify() For all threads waiting on this object’s monitor (by using any one of the wait() methods), the method notify() notifies any one of them to wake up arbitrarily.
  2. 4.2. notifyAll() This method simply wakes all threads that are waiting on this object’s monitor.

How does notifyAll work in Java?

notifyAll() wakes up all threads that are waiting on this object’s monitor. A thread waits on an object’s monitor by calling one of the wait methods. The awakened threads will not be able to proceed until the current thread relinquishes the lock on this object.

How do I fix IllegalMonitorStateException?

The IllegalMonitorStateException can be resolved by calling the wait() , notify() and notifyAll() methods after acquiring an object lock, i.e. within a synchronized block or method.

What is wait () in Java?

Simply put, wait() is an instance method that’s used for thread synchronization. It can be called on any object, as it’s defined right on java. lang. Object, but it can only be called from a synchronized block. It releases the lock on the object so that another thread can jump in and acquire a lock.

How do I fix Java Lang IllegalMonitorStateException?

How wait notify and notifyAll works in Java?

The wait() method causes the current thread to wait until another thread invokes the notify() or notifyAll() methods for that object. The notify() method wakes up a single thread that is waiting on that object’s monitor. The notifyAll() method wakes up all threads that are waiting on that object’s monitor.

Why wait () notify () and notifyAll are in object class?

If wait() and notify() were on the Thread instead then each thread would have to know the status of every other thread and there is no way to know thread1 that thread2 was waiting for any resource to access. Hence, notify, wait, notifyAll methods are defined in object class in Java.

What is InterruptedException in Java?

java.lang.InterruptedException. Thrown when a thread is waiting, sleeping, or otherwise occupied, and the thread is interrupted, either before or during the activity. Occasionally a method may wish to test whether the current thread has been interrupted, and if so, to immediately throw this exception.

What is notify and notifyAll in Java?

1. Notification. In case of multiThreading notify() method sends the notification to only one thread among the multiple waiting threads which are waiting for lock. While notifyAll() methods in the same context sends the notification to all waiting threads instead of single one thread.

How do you sync a method in Java?

Java Synchronized Method

  1. //example of java synchronized method.
  2. class Table{
  3. synchronized void printTable(int n){//synchronized method.
  4. for(int i=1;i<=5;i++){
  5. System.out.println(n*i);
  6. try{
  7. Thread.sleep(400);
  8. }catch(Exception e){System.out.println(e);}

What are wait () notify () and notifyAll () methods?

How do I use wait and notifyAll?

notifyAll() is also present in java. lang . Object class. To call notifyAll() method on any object they should be the owner of that object i.e, the thread should be inside synchronized area….Java.

wait() notifyall()
4. It is used for interthread communication It is implemented in Object class as final methods

Why wait () notify () and notifyAll () must be called from synchronized block or method in Java?

Calling notify() or notifyAll() methods issues a notification to a single or multiple threads that a condition has changed and once the notification thread leaves the synchronized block, all the threads which are waiting for fight for object lock on which they are waiting and lucky thread returns from wait() method …

Why wait () notify () and notifyAll () methods have to be called from synchronized method or block?

How do you fix InterruptedException?

Let’s take a look at them.

  1. 4.1. Propagate the InterruptedException. We can allow the InterruptedException to propagate up the call stack, for example, by adding a throws clause to each method in turn and letting the caller determine how to handle the interrupt.
  2. 4.2. Restore the Interrupt.
  3. 4.3. Custom Exception Handling.