net.bytebuddy.instrumentation.method.bytecode.bind.annotation

Annotation Type Origin

@Documented
 @Retention(value=RUNTIME)
 @Target(value=PARAMETER)
public @interface Origin

The origin annotation provides some meta information about the source method that is bound to this method where the binding is dependant of the parameter's type:

1. If the annotated parameter is of type Method, the parameter is assigned a reference to the method it intercepts.
2. If the annotated parameter is of type Class, the parameter is assigned a reference of the type of the instrumented type.
3. If the annotated parameter is of type String, the parameter is assigned a string describing a unique method signature of the method it intercepts. This string is a concatenation of:
   • The method's name
   • The ( symbol
   • A list of the method's parameters' descriptors
   • The ) symbol
   • The descriptor of the method's return type
   This unique signature allows the unambiguous identification of a particular class's methods while avoid the rather expensive creation of a Method instance.
4. If the annotated type is MethodHandle, a handle of the intercepted method is injected. A MethodHandle is stored in a class's constant pool and does therefore not face the same runtime performance limitations as a Method reference. Method handles are only supported for byte code versions starting from Java 7.
5. If the annotated type is MethodType, a description of the intercepted method's type is injected. Method type descriptions are only supported for byte code versions starting from Java 7.

Any other parameter type will cause an IllegalStateException.

See Also:

MethodDelegation, TargetMethodAnnotationDrivenBinder

Optional Element Summary

Optional Elements

Modifier and Type	Optional Element and Description
boolean	cacheMethod If this value is set to true and the annotated parameter is a Method type, the value that is assigned to this parameter is cached in a static field.

Element Detail

cacheMethod

public abstract boolean cacheMethod

If this value is set to true and the annotated parameter is a Method type, the value that is assigned to this parameter is cached in a static field. Otherwise, the instance is looked up from its defining Class on every invocation of the intercepted method.

Method look-ups are normally cached by its defining Class what makes a repeated look-up of a method little expensive. However, because Method instances are mutable by their AccessibleObject contact, any looked-up instance needs to be copied by its defining Class before exposing it. This can cause performance deficits when a method is for example called repeatedly in a loop. By enabling the method cache, this performance penalty can be avoided by caching a single Method instance for any intercepted method as a static field in the instrumented type.

Returns:

true if the annotated Method parameter should be assigned a cached instance. For any other parameter type, this value is ignored.

Default:

false