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( ).