The Object.wait() method is used to temporarily cede possession of a lock so that another requesting thread can proceed. It must always be used inside a synchronized block or method. To let the waiting thread resume, the requesting thread must notify it. Furthermore, the wait() method should be invoked in a loop that checks if a condition predicate holds. Note that a condition predicate is not the same as the condition expression in the loop. For example, the condition predicate for removing an element from a vector is !isEmpty() whereas the condition expression for the while loop condition is isEmpty(). The correct way to invoke wait() is shown below.
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