How do I get direct superclass and interfaces of a class?

Java reflection also dealing with inheritance concepts. You can get the direct interfaces and direct superclass of a class by using method getInterfaces() and getSuperclass() of java.lang.Class object.

  • getInterfaces() will returns an array of Class objects that represent the direct super interfaces of the target Class object
  • getSuperclass() will returns the Class object representing the direct super class of the target Class object or null if the target represents Object class, an interface, a primitive type, or void.

 

package org.kodejava.example.lang.reflect;

import javax.swing.*;
import java.util.Date;

public class GetSuperClassDemo {
    public static void main(String[] args) {
        GetSuperClassDemo.get(String.class);
        GetSuperClassDemo.get(Date.class);
        GetSuperClassDemo.get(JButton.class);
        GetSuperClassDemo.get(Timer.class);
    }

    public static void get(Class clazz) {
        //
        // Gets array of direct interface of clazz object
        //
        Class[] interfaces = clazz.getInterfaces();

        System.out.format("Direct Interfaces of %s:%n",
                clazz.getName());
        for (Class clz : interfaces) {
            System.out.println(clz.getName());
        }

        //
        // Gets direct superclass of clazz object
        //
        Class superclz = clazz.getSuperclass();
        System.out.format("Direct Superclass of %s: is %s %n",
                clazz.getName(), superclz.getName());
        System.out.println("====================================");
    }
}

Here is the result of the code snippet:

Direct Interfaces of java.lang.String:
java.io.Serializable
java.lang.Comparable
java.lang.CharSequence
Direct Superclass of java.lang.String: is java.lang.Object 
====================================
Direct Interfaces of java.util.Date:
java.io.Serializable
java.lang.Cloneable
java.lang.Comparable
Direct Superclass of java.util.Date: is java.lang.Object 
====================================
Direct Interfaces of javax.swing.JButton:
javax.accessibility.Accessible
Direct Superclass of javax.swing.JButton: is javax.swing.AbstractButton 
====================================
Direct Interfaces of javax.swing.Timer:
java.io.Serializable
Direct Superclass of javax.swing.Timer: is java.lang.Object 
====================================

Wayan

Programmer, runner, recreational diver, live in the island of Bali, Indonesia. Mostly programming in Java, Spring Framework, Hibernate / JPA. Support me by donating.

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