Steps to Reproduce

extend GenericForwardComposer

public class MyGenericForwardComposer extends GenericForwardComposer { 
}

apply the composer to any zk component

 <div apply="MyGenericForwardComposer"/>

Start in debug mode, and set an ExceptionBreakpoint for java.lang.NoSuchFieldException

Current Result

The exception break point is triggered 64 times even for this very simple scenario (the same fields are queried multiple times)
This happens everytime the page is refreshed. For every user.

The effect multiplies with deeper class hierarchies, and multiple composers in a single page.

Expected Result

Caching results to avoid recurring exceptions.

Debug Info

Root Cause

Classes#getAnyField
https://github.com/zkoss/zk/blob/master/zcommon/src/org/zkoss/lang/Classes.java#L1214-L1225
same with Classes#getAnyMethod
https://github.com/zkoss/zk/blob/master/zcommon/src/org/zkoss/lang/Classes.java#L1176-L1194

Workaround

SelectorComposer which uses Annotations scanning instead of naming conventions doesn't have this problem.