Deadlock in Java is a situation that can occur in multithreading when two or more threads are blocked forever, waiting for each other. This happens when a thread is waiting for an object lock that is acquired by another thread, and the second thread is waiting for an object lock that is acquired by the first thread. Since both threads are waiting for each other to release the lock, the condition is called deadlock.
Deadlock can occur when multiple threads need the same locks but obtain them in different orders. A Java multithreaded program may suffer from the deadlock condition because the synchronized keyword causes the executing thread to block while waiting for the lock, or monitor, associated with the specified object.
To avoid deadlock, it is important to ensure that threads do not wait indefinitely for each other to finish. One way to do this is to avoid cyclic dependencies for resources between threads. Another way is to use a timeout when waiting for a lock.
In summary, deadlock in Java is a situation where two or more threads are blocked forever, waiting for each other due to a cyclic dependency for resources between threads. It can be avoided by ensuring that threads do not wait indefinitely for each other to finish and by avoiding cyclic dependencies for resources between threads.
