String concatenation optimization reverted to old way

Name: rlT66838 Date: 05/17/2000


I was looking at bytecode generated by javac and noticed a curious difference
between jdk1.2.2 and jdk1.3 final

javac 1.2.2 had a revised code generation for concatenation such that

  aString = string1 + string2;

generates

  aString = new StringBuffer(String.valueOf(string1)).append(string2);

But, javac 1.3 generates

  aString = new StringBuffer().append(string1).append(string2);

The 1.3 code generation is the same as that generated by older javac versions
(sometime prior to 1.2.2). Is that intentional? Either the 1.3 writers failed
to incorporate a late improvement from the 1.2.2 branch, or someone decided
that the 1.2.2 method wasn't such a good idea.

I'm just calling this to your attention in case it's an oversight.
(Review ID: 105010)
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