Confusion about string objects

[Roger Fed]

Can anyone explain the meaning that string objects is immutable?

[Hussein Baghdadi]

Basically it means that once you created a String, you can't change it (one of its characters for example).
Any operation like swapping a character, upper casing it and others is going to create a new String.

[Rob Spoor]

Note that you can't change the String object, but changing the String reference is possible (if the variable isn't final):

String s1 = "Hello World";
String s2 = s1; // both refer to the same "Hello World" object
s2 = s2.substring(0, 5);
// s2 is the new "Hello" String, s1 is still the original "Hello World" String

[Sunny Bhandari]

Hi Roger, you can see the source code of String API methods to research more on this topic....

It will give you more knowledge and confidence on this popular question...