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How to check string for equality?

package com.javacoderanch.example.lang;

public class StringEquals
{
    public static void main(String[] args)
    {
        String s1 = "Hello World";
        String s2 = new String("Hello World");

        //
        // To compare string for equality we must use the equals method of
        // the string object. This ensure that the string content is compared
        // and not the object reference of the both string. This process will
        // return true as s1 and s2 have the same value.
        //
        if (s1.equals(s2))
        {
            System.out.println("String is equal");
        }
        else
        {
            System.out.println("String is unequal");
        }

        //
        // Do not use the == operator to compare string for it's content, the ==
        // operator check return true only if the object has the same reference. This
        // process will return false as the string references to a different object.
        //
        if (s1 == s2)
        {
            System.out.println("String is equal");
        }
        else
        {
            System.out.println("String is unequal");
        }
    }
}