Java: changing the value of a String

September 6, 2011 — Alexey Ivanov

Consider this piece of code:

String s = "abc";
m(s);
System.out.println(s);

The last line prints not the expected abc but something different, for example dbc. How does m() do it?

Jose Says:
July 2, 2012 at 06:26
I give up, how do you do it? It should not be possible since String is immutable and there are no methods in String to alter it. I imagine you would have to somehow get the address location of s and have it point to a new String. Maybe you can email me the solution, I am very curious.

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- Alexey Ivanov Says:
  July 5, 2012 at 23:30
  Jose, you are right String is immutable you can’t change the value stored in it after the object is created. Yet there’s a way to do it…– it’s reflection.
  
  See the complete solution in Is it possible to change a String?.
  
  Reply
Is it possible to change a String « Programming is my life Says:
July 5, 2012 at 23:17
[…] was my answer to the question How can the value of string be changed? I was asked this question on a job […]

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