Java String.intern()

The method intern() creates an exact copy of a String object in the heap memory and stores it in the String constant pool.

Note that, if another String with the same contents exists in the String constant pool, then a new object won’t be created and the new reference will point to the other String.

Available Signatures


public String intern()



public void whenIntern_thenCorrect() {
    String s1 = "abc";
    String s2 = new String("abc");
    String s3 = new String("foo");
    String s4 = s1.intern();
    String s5 = s2.intern();

    assertFalse(s3 == s4);
    assertTrue(s1 == s5);