A monitor, in our context, is a synchronized mechanism that controls concurrent access to an object. Monitors help prevent multiple threads from accessing a monitored object at the same time. The JVM automatically switches between three monitor implementation methods. The three implementation methods are illustrated as follows:
The initial lock of a Java object uses biased locking. That method ensures only the locking thread can lock the object. With this approach, the JVM installs a thread pointer in the Java object. When a second thread attempts to lock the Java object, the JVM switches to the basic locking monitor ...
