public class TestStr { public static void main(String[] args) { test1(); } public static void test1(){ String a=new String("abc"); a.intern(); String b="abc"; System.out.println(b==a.intern()); System.out.println(a==b); } public static void test2(){ String a=new String("abc")+new String("d"); a.intern(); //System.out.println(a==a.intern()); String b="abcd"; //System.out.println(b==b.intern()); System.out.println(a==b); } }