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My String won't trim

 
Elouise Kivineva
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I have a GUI with a JPassword field named pswrd.
When I read the entered password I save it in a String
named password and trim to get out leading and trailing
empty spaces (user pressed the space bar).

but when I print the password (using a JOptionPane)

to check that the empty spaces are gone, they never are.
Why, and what can I do about it?
Thanks!
 
Joe Pluta
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This is a standard mistake when working with Strings. Strings are immutable, meaning they do not change. The syntax "password.trim();" does nothing to the original String, it simply returns a NEW String with the spaces trimmed off. The following modification will work:
password = password.trim();
Hope this helps.
Joe
 
Ransika deSilva
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Hello,
Hope this too clarify the answer, according to the API specification of the String class,
trim()
Returns a copy of the string, with leading and trailing whitespace omitted.
Important thing to note here is that, it returns a String.
Better check the API if you get similar problems.
Cheers...........
 
Amin Rais
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String in Java is immutable. So you can't change it instead get the new trimmed String.
 
Elouise Kivineva
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Oh geez! I really should have seen that...
Thanks ya'll, Elouise
 
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