Invocation (Method method) { Invocation invocation = myAccessorInvocations.get(method); if (invocation != null) return invocation; invocation = myInvocationCache.getInvocation(method); if (invocation != null) return invocation; invocation = createAccessorInvocation(method); myAccessorInvocations = myAccessorInvocations.plus(method, invocation); return invocation; }