I'm newbie to java.
class Demo{
    public static void main(String[] args) {
        String s1=new String("abc"); 
        String s2=new String("abc"); 
        String s3="xyz";
        String s4="xyz";
        System.out.println(s1==s2); //line 7
        System.out.println(s3==s4); //line 8
    }
}
I just don't understand why line 7 got false and line 8 got true.
I would be so grateful if someone explain me this.
