Arrays and Strings - Beginning Java - page 163

String string1 = "Too many ";
String string2 = "cooks";
String string3 = "Too many cooks";
// Make string1 and string3 refer to separate strings that are
identical
string1 += string2;
// Display the contents of the strings
System.out.println("Test 1");
System.out.println("string3 is now: " + string3);
System.out.println("string1 is now: " + string1);
if(string1 == string3) { // Now test for identity
System.out.println("string1 == string3 is true." +
" string1 and string3 point to the same
string");
} else {
System.out.println("string1 == string3 is false." +
" string1 and string3 do not point to the same
string");
}
// Now make string1 and string3 refer to the same string
string3 = string1;
// Display the contents of the strings
System.out.println("\n\nTest 2");
System.out.println("string3 is now: " + string3);
System.out.println("string1 is now: " + string1);
if(string1 == string3) { // Now test for identity
System.out.println("string1 == string3 is true." +
" string1 and string3 point to the same
string");
} else {
System.out.println("string1 == string3 is false." +
" string1 and string3 do not point to the same
string");
}
}
MatchStrings.java
You have created two scenarios in this example. In the first, the variables string1 and string3 refer to
separate String objects that happen to encapsulate identical strings. In the second, they both reference
the same String object. The program produces the following output:
Test 1
string3 is now: Too many cooks
string1 is now: Too many cooks
string1 == string3 is false. string1 and string3 do not point to the
same string