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Interface-2

Example1:-    A.java

interface A
{
int a;
}

Output:-
C:\JAVATECH>javac A.java
A.java:3: error: = expected
int a;
     ^
1 error
Explanation: - Interface variable must initialize at declaration time because by default interface variables are public static and final.

Example2:-    A.java

interface A
{
int a=100;
}

Output:-
C:\JAVATECH>javac A.java
C:\JAVATECH>javap A
Compiled from "A.java"
interface A {
  public static final int a;
}
 Explanation: - by default interface variables are public static and final.

Example3:-    A.java

interface A
{
public static final int a=100;
}

Output:-
C:\JAVATECH>javac A.java
C:\JAVATECH>javap A
Compiled from "A.java"
interface A {
  public static final int a;
}

Example4:-    A.java

interface A
{
static public final int a=100;
}
Output:-

C:\JAVATECH>javac A.java
C:\JAVATECH>javap A
Compiled from "A.java"
interface A {
  public static final int a;
}
Explanation: - Here public, static and final all are modifiers, and order of modifiers can interchange.

Example5:-    A.java
interface A
{
final  static public int a=100;
}
Output:-
C:\JAVATECH>javac A.java
C:\JAVATECH>javap A
Compiled from "A.java"
interface A {
 public static final int a;   

}

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