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0152 The Object Class

Object is a superclass of all other classes. Therefore, Object can refer to an object of any other class. Also, a variable of type Object can also refer to any array. Object defines the following methods, which means that they are available in every object. Return Method Purpose Object clone( ) Creates a new object that is the same as the object being cloned. boolean equals(Object object) Determines whether one object is equal to another. void finalize( ) Called before an unused object is recycled. Class getClass( ) Obtains the class of an object at run time. int hashCode( ) Returns the hash code associated with the invoking object. void notify( ) Resumes execution of a thread waiting on the invoking object. void notifyAll( ) Resumes execution of all threads waiting on the invoking object. String toString( ) Returns a string that describes the object. void wait( ) Waits on another thread of execution. void wait(long milliseconds) Waits on another thread of execution. void wait(long milliseconds, int nanoseconds) Waits on another thread of execution. getClass( ), notify( ), notifyAll( ), and wait( ) are final. The equals( ) method compares the contents of two objects. It returns true if the objects are equivalent, and false otherwise. The toString( ) method returns a string that contains a description of the object. toString( ) method is automatically called when an object is output using println( ).