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Null pointer not found

Swamy Nathan
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Joined: May 16, 2004
Posts: 187
Ok somebody explain this-

output:
john von
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Joined: Apr 13, 2004
Posts: 49
explain what?
Swamy Nathan
Ranch Hand

Joined: May 16, 2004
Posts: 187
If the following throws java.lang.NullPointerException
s=null;
s=s.concat("a");

How come this
("1"+null+2) does not?

And also in other places.

Am I correct in thinking this is because internally a StringBuffer is used in all cases and stringBuffer.append(null) just adds the text null.
Anyway I thought it was interesting because I was expecting a nullpointer to be thrown and it was not.
 
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subject: Null pointer not found