String is an immutable object.
Then how can the following code be justified.
String s1 = ?ABC?;
String s1 = s1+?XYZ?;
s.o.p(s1);
The output is ABCXYZ, which is the value of s1 ?
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Answer Posted / amr
actually its a compiler error , variable already defined ..
but i'll answer the other part ,
String is immutable but does it make sense to write
String S1= abc;
S1=s1+"def";
YEAH its immutable and what happens behind the scene :
a new temporary String is created and using StringBuffer
which mutable class then appending then returning the
temporary string , thats the meaning of String is immutable
but StringBuffer is mutable , so if u r gonna use intensive
String manipulation u better go for StringBuffer because
String concatenation will result in more lines of code in
the byte code file generated when we compile .
this is a very frequent interview question .
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