deduplicating lambda methods

[B. Blaser]

On 27 March 2018 at 19:33, Vicente Romero <vicente.romero at oracle.com> wrote:
>
>
> On 03/27/2018 12:58 PM, Brian Goetz wrote:
>>
>> It looks like there were no changes in the outcome, perhaps because there
>> were no within-file duplications in the JDK.  (Which I believe.)  A more
>> streams/Rx/CompletableFuture-heavy codebase would likely see an improvement.
>
>
> right, no difference :(, let's see what happens with Liam's numbers :)
>
> Vicente

I perhaps found at least one trivial lambda duplicate in the JDK (javac) here:

http://hg.openjdk.java.net/jdk/jdk/file/814bd31f8da0/src/jdk.compiler/share/classes/com/sun/tools/javac/code/Types.java#l450

I tried to reproduce it like this (is that right?):

import java.util.List;
import java.util.Set;

public class Test {
    class CaputureScanner extends SimpleVisitor {
        public Void visitClassType(Type.ClassType t, Set<Type> seen) {
            if ( t.isCompound() ) {
                directSupertypes(t).forEach(s -> visit(s, seen));
            } else {
                t.allparams().forEach(ta -> visit(ta, seen));
            }
            return null;
        }
    }
    public static class SimpleVisitor {
        public Void visit(Type t, Set<Type> seen) { return null; }
    }
    public static class Type {
        public boolean isCompound() { return false; }

        public static class ClassType extends Type {
            public List<Type> allparams() { return null; }
        }
    }
    public List<Type> directSupertypes(Type t) { return null; }
}

which is correctly de-duplicated.

But stats don't show any difference, are they missing something?

Bernard