Java Examples - instanceOf Keyword Usage

Java Examples

instanceof Java is a binary operator, similar to ==,>, <, etc. operator.

instanceof is Java reserved keywords. Its role is to test whether it is the left object is an instance of the class to its right to return boolean data types.

The following example creates displayObjectClass () method to demonstrate Java instanceOf keyword usage:

/*
 author by w3cschool.cc
 Main.java
 */
import java.util.ArrayList;
import java.util.Vector;

public class Main {

public static void main(String[] args) {
   Object testObject = new ArrayList();
      displayObjectClass(testObject);
   }
   public static void displayObjectClass(Object o) {
      if (o instanceof Vector)
      System.out.println("对象是 java.util.Vector 类的实例");
      else if (o instanceof ArrayList)
      System.out.println("对象是 java.util.ArrayList 类的实例");
      else
      System.out.println("对象是 " + o.getClass() + " 类的实例");
   }
}

The above code is run output is:

对象是 java.util.ArrayList 类的实例

Java Examples