Question

Possible Duplicate:
Java question about autoboxing and object equality / identity

Integer i1 = 10;
Integer i2 = 10;
Integer i3 = 210;
Integer i4 = 210;

if(i1 ==i2){
      System.out.println("True");
}else{
      System.out.println("False");
}
if(i3==i4){
       System.out.println("True");
}else{
       System.out.println("False");
}
if(Integer.valueOf(10) ==Integer.valueOf(10)){
       System.out.println("True");
}else{
      System.out.println("False");
}
if(Integer.valueOf(210) ==Integer.valueOf(210)){
       System.out.println("True");
}else{
       System.out.println("False");
}

The answer is

True

False

True

False

Why it is giving false for 2 and 4 condition ?

Answer 1

Note that Integer is an object, not a primitive. You’re comparing different object instances.

For this particular example, it’s worth reading about boxing.