Java: Can someone explain this code please.

Question

hello why this conditions is not true

String a =new String("hello world");

if(a=="hello world")
{
System.out.println(1);
}
else{
System.out.println(0);
}

is It related to objects? because Ive just started with objects I dont have much knowledge about it

Answer 1

Change the "if" part to:

if(a.equals("hello world"))

String comparison must use equals method, the == operator returns true only if you compare two objects that refer to the same thing. e.g.

String a = "Hello, world";
String b = a;
System.out.println(b == a);

Hth, cmiiw

Answer 2

It would also work with the ==, if you change the first line to

String a = "hello world" ;

Because string literals are interned in a special memory area. By calling new String you told the JVM to put your String on the heap like a normal object.

Answer 3

thank you guys, I got it now.

Answer 4

@1of3 can you suggest me where can I learn more about it.