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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.


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