Superclass of all classes:
- Object is the implicit superclass of all classes in Java.
- All classes inherit from Object, so a reference variable of type Object can reference any object or array.
Methods defined in the Object class:
- The following are the main methods provided by the Object class:
- Object clone(): Creates a new object identical to the original object.
- boolean equals(Object object): Checks whether two objects are equal.
- void finalize(): Called before an unused object is recycled (garbage collected).
- Class> getClass(): Returns the object's class at run time.
- int hashCode(): Returns the hash code associated with the object.
- void notify(): Resumes the execution of a thread that is waiting on the object.
- void notifyAll(): Resumes the execution of all threads waiting on the object.
- String toString(): Returns a string that describes the object.
- void wait() / void wait(long milliseconds) / void wait(long milliseconds, int nanoseconds): Makes the object wait until another thread notifies.
Final methods:
The getClass(), notify(), notifyAll() and wait() methods are declared final and cannot be overridden.
Frequently overwritten methods:
equals(Object object): Compares two objects and returns true if they are equivalent.
toString(): Returns a textual description of the object. Automatically called when printing an object with println().
Use of generics in the getClass() method:
- The return syntax of the getClass() method uses generic types, which allow the data type of a class or method to be parameterized.
- The Object class offers a set of essential methods that can be used or overridden in any Java class, allowing the basic behavior of any object.
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