Hey,
I'm new to the OpenJDK and not sure (yet) how the procedure especially for
new bugs/enhancement is. So I apologise upfront if I made any mistakes.
I'm working mostly with the Spring-Framework/Spring-Boot in my current
projects. In these frameworks a lot of dynamic proxying can happen.
Recently, I noticed that the JDK in versions 8 up to the current snapshots
produces some allocations coming from
sun.reflect.annotation.AnnotationInvocationHandler.invoke() we could avoid
in the majority of cases. Only the check for equality needs the actual
parameter types - all other cases only need the parameter count which JDK 8
luckily provides with Method.getParameterCount().
What about changing the current behaviour to something like my attached
proposal? I'd be happy if someone is willing to sponsor this change. Again -
if I made any mistakes here, please let me know for the next time.
Cheers,
Christoph Dreis
================================
Reduce allocations in
sun.reflect.annotation.AnnotationInvocationHandler.invoke()
diff -r ba70dcd8de76 -r 86bbc5442c1d
src/java.base/share/classes/sun/reflect/annotation/AnnotationInvocationHandl
er.java
---
a/src/java.base/share/classes/sun/reflect/annotation/AnnotationInvocationHan
dler.java Fri Nov 11 13:11:27 2016 +0000
+++
b/src/java.base/share/classes/sun/reflect/annotation/AnnotationInvocationHan
dler.java Mon Nov 14 19:04:33 2016 +0100
@@ -57,13 +57,13 @@
public Object invoke(Object proxy, Method method, Object[] args) {
String member = method.getName();
- Class<?>[] paramTypes = method.getParameterTypes();
+ int parameterCount = method.getParameterCount();
// Handle Object and Annotation methods
- if (member.equals("equals") && paramTypes.length == 1 &&
- paramTypes[0] == Object.class)
+ if (member.equals("equals") && parameterCount == 1 &&
+ method.getParameterTypes()[0] == Object.class)
return equalsImpl(proxy, args[0]);
- if (paramTypes.length != 0)
+ if (parameterCount != 0)
throw new AssertionError("Too many parameters for an annotation
method");
switch(member) {
