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How can this be if I can create a String, giving it a value. Then, I can simply overwrite its value like this:

String a="abc";
a="def";

How is it possible that I can change the value of a? I must be missing something here. I understand that Strings literals are used whenever creating a String object, rather than creating a new instance of String every time

Please help, thanks.

amigo21
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  • Sorry guys, this is a dumb question. I should've known now referencing works with Strings – amigo21 Jul 31 '15 at 18:03
  • No worries, but please do try googling next time (or, if you did, let us know what you searched for and why it didn't answer your question). I didn't remember the marked duplicate offhand, but a search for "java string immutable" had several highly relevant answers (including the one I marked this as a duplicate of). – yshavit Jul 31 '15 at 18:05

2 Answers2

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Your not changing its value you are creating a new String. Technically your variable changes its value (memory location its pointing to) to reference a new String object but it is pointing to the new String object not the same String object.

You aren't actually changing the value of the original String object you are just referencing a new String so while the value of your variable does change you aren't actually changing the original String object...Hope that makes sense.

brso05
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String a="abc";//creating string literal object
a="def";

You are actually changing the reference of a to a new object created by the String literal "def".

String is immutable means that you cannot change the object itself, but you can change the reference to the object. Changing an object means to use its methods to change one of its fields.

SatyaTNV
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