Question About MethodHandles.findSpecial

[John Rose]

On May 5, 2009, at 10:48 PM, Fredrik Öhrström wrote:

> So my question was, and still is, :-) , why would you
> call a constructor through a MethodHandle?

It would let you emulate the super(...) call in a language which needs  
to make a subclass of some Java class with a non-trivial constructor,  
without forcing the language to generate bytecodes for that subclass's  
constructor call.  It's a pretty small use-case, and the workaround is  
pretty reasonable:  just generate the bytecodes containing the  
invokespecial call.  After all, the number of superclass constructors  
is much smaller, usually, than the number of overrideable and callable  
superclass methods.  (Generating bytecodes is a  burden on very small  
JVMs, but not elsewhere.)

BTW, I just pushed out the first big bundle of Java code changes for  
the 292 RI, into OpenJDK proper.  The latest version of findSpecial  
may be viewed here:
   http://hg.openjdk.java.net/jdk7/tl/jdk/file/tip/src/share/classes/java/dyn/MethodHandles.java

-- John