Logo Questions Linux Laravel Mysql Ubuntu Git Menu
 

Getting strange output when printing result of a string comparison

Tags:

java

string

I am facing a problem with this line (commented below):

System.out.println("Using == ::"+s3==s4)

which outputs false.

However, System.out.println(s3==s4) outputs true.

Now, I am not able to understand why I am getting this result:

public class string {
    public static void main(String[] args){
        String s3="Shantanu";
        String s4=s3;
        String s1=new String("java");
        String s2=new String("javaDeveloper");

        System.out.println("Using Equals Method::"+s1.equals(s2));
        System.out.println("Using Equals Method::"+s3.equals(s4));
        System.out.println("Using == ::"+s3==s4);//Problem is here in this line
        System.out.println(s1+"Directly printing the s2 value which is autocasted from superclass to string subclass ");
        System.out.println("Directly printing the s1 value which is autocasted from superclass to string subclass "+s2);
        System.out.println(s3);
    }
}
Output-Using Equals Method::false
Using Equals Method::true
Using == ::false
java Directly printing the s2 value which is autocasted from superclass to string subclass
Directly printing the s1 value which is autocasted from superclass to string subclass javaDeveloper
like image 541
Shantanu Nandan Avatar asked Aug 14 '13 17:08

Shantanu Nandan


1 Answers

You're missing a set of brackets:

System.out.println("Using == ::" + (s3==s4));

In your version, "Using == ::" + s3 is being compared via == to s4, which isn't what you want.

In general, + has a higher precedence than ==, which is why "Using == ::" + s3==s4 is being evaluated as ("Using == ::" + s3) == s4.

like image 167
arshajii Avatar answered Sep 23 '22 04:09

arshajii