What is the best way to do string concatenation?

[Franco Finstad]

What is the best way to do string concatenation? I read that using "+" on a string object uses StringBuffer behind the scenes so it seems that using StringBuffer explicitly is unecessary.
So, should I do:
myString + "foo" + "bar";
or
myStringBuffer.append("foo").append("bar");
Any help is appreciated.

[Cindy Glass]

If you do the first you will end up with a String object that is immutable.
If you do the second you will end up with a StringBuffer object that is mutable.
Which do you WANT?

[Arvind Dua]

Besides what Cindy said another criteria for deciding whether to use a StringBuffer or String concatenation is the number of String Objects you need to concatenate. If it is only 2 both are equal in terms of performance . But if the number of Strings you want to concatenate is more, I will certainly prefer StringBuffer because everytime I concatenate two Strings a new Object is created( because String objects are immutable and cannot be modified) but if its a StringBuffer, the same Object is modified to hold the concatenated String and no new Objects are created.
Hope this helps !!
[ May 22, 2003: Message edited by: Arvind Dua ]

[Junilu Lacar]

You might want to consider readability before trying to second guess the compiler's optimization capabilities. A succession of append()s to a StringBuffer would probably throw another programmer off at first glance. Try to write clear code first; use a profiler to find bottlenecks.
[ May 22, 2003: Message edited by: Junilu Lacar ]