Skip to main content

Interface-3

Example6:-    A.java

interface A
{
void disp();
}

Output:-
C:\JAVATECH>javac A.java
C:\JAVATECH>javap A
Compiled from "A.java"
interface A {
  public abstract void disp();
}
Explanation: - Interface contains only abstract methods only and all interface methods are by default public and abstract.

Example7:-    A.java

interface A
{
public abstract void disp();
}

Output:-
C:\JAVATECH>javac A.java
C:\JAVATECH>javap A
Compiled from "A.java"
interface A {
  public abstract void disp();
}

Example8:-    A.java

interface A
{
abstract public void disp();
}

Output:-
C:\JAVATECH>javac A.java
C:\JAVATECH>javap A
Compiled from "A.java"
interface A {
  public abstract void disp();
}

Example9:-    A.java

interface A
{
  void disp();
  int set();
}

Output:-
C:\JAVATECH>javac A.java
C:\JAVATECH>javap A
Compiled from "A.java"
interface A {
  public abstract void disp();
  public abstract int set();
}

Example10:-    A.java

interface A
{
void disp()
{
System.out.println("This is concrete method");
}
}

Output:-
C:\JAVATECH>javac A.java
A.java:4: error: interface abstract methods cannot have body
{
^
1 error
Explanation: - Interface contains only abstract methods, cannot contains concrete methods.


Comments

Popular posts from this blog

Inheritance-4

Example10:- class Student { Student() { System.out.println("This is super class Zero argument constructor"); } Student(String s) { System.out.println("This is super class One argument constructor"); } } class Test extends Student { Test() { super(null); System.out.println("This is sub class Zero argument constructor"); } public static void main(String[]args) { Test t=new Test(); } } Output:- C:\JAVATECH>javac Test.java C:\JAVATECH>java Test This is super class One argument constructor This is sub class Zero argument constructor Example11:- class Student { Student() { System.out.println("This is super class Zero argument constructor"); } Student(String s) { System.out.println("This is super class One argument constructor"); } } class Test extends Student { Test() { super(); super(null); System.out.println("This is su...

Regarding class files

Class files:- Regarding class file or dot class file also known as byte code of class, in a java programming language we can use any number of classes in our program. After compilation all classes convert into individual   .class   file. Example:- class A { } class B { } class C { } class Student { public static void main(String[]args) { System.out.println("Well-come to my java blog"); } } We can save above program to any   classname.java   or we can use any other   name.java,   there is no compulsion for java file name. But recommended to save by that class name which having main method. I saved the above file to   Student.java   name .   Before compilation my   C:\JAVATECH   folder contain only one java file. Student.java For  compilation. C:\JAVATECH>javac  Student.java After compilation   my   C:\JAVATECH   folder contains five files, on...

inheritance

INHERITANCE:- Inheritance is the process of code re-usability, using this property software or applications can develop in less time or can develop rapidly. Inheritance increases the readability of code and decrease redundancy or repetition of code or reduces size of code. Use of previously developed code in future any number of times is called inheritance. Through inheritance variables and methods of class can inherited. Types of Inheritance:- 1)         Single or Single level inheritance 2)         Multilevel inheritance 3)         Hierarchical inheritance Java does not support to multiple inheritance. Single or single level inheritance:- In a single inheritance a class is inherited by a single class. In a single or single level inheritance a sub class having only one super class directly or indirectly. Syntax: -        class Subclass ex...