intern() behaving differently in Java 6 and Java 7

Question

class Test {
    public static void main(String...args) {
        String s1 = \"Good\";
        s1 = s1 + \"morning\";
        System.out.println(s1.intern());
              


        

Answer 1

In jdk6: String s1="Good"; creates a String object "Good" in constant pool.

s1=s1+"morning"; creates another String object "morning" in constant pool but this time actually JVM do: s1=new StringBuffer().append(s1).append("morning").toString();.

Now as the new operator creates an object in heap therefore the reference in s1 is of heap not constant pool and the String s2="Goodmorning"; creates a String object "Goodmorning" in constant pool whose reference is stored in s2.

Therefore, if(s1==s2) condition is false.

But what happens in jdk7?