Class Object : Class Object « Class Definition « Java Tutorial






  1. All the classes defined are subclasses by default.
  2. Object is a superclass of every class.
  3. The inheritance happens automatically.
  4. Your classes will inherit members from the class Object.
MethodPurpose
toString()returns a string describing the current object
equals()compares two objects
getClass()returns a Class that identifies the class of the current object.
hashCode()calculates a hashcode for an object
notify()wakes up a thread associated with the current object.
notifyAll()wakes up all threads associated with the current object.
wait()causes a thread to wait


class Dog{
  public Dog(String aType){
  }
}
public class MainClass{
  public static void main(String[] a){
    Dog d = new Dog("a");
    Class objectType = d.getClass();             
    System.out.println(objectType.getName());      
  }
}
Dog








5.17.Class Object
5.17.1.Getting java.lang.Class: Information about your object
5.17.2.Comparing Objects
5.17.3.Class Object
5.17.4.Storing a reference to the String object as type Object
5.17.5.The 'Class' class also brings the possibility of creating an object without using the new keyword.
5.17.6.Assignment with objects is a bit tricky.
5.17.7.Demonstrate Run-Time Type Information.