org.apache.tapestry5.plastic
Interface MethodInvocation

All Superinterfaces:

AnnotationAccess, MethodInvocationResult

All Known Implementing Classes:

AbstractMethodInvocation

public interface MethodInvocation
extends MethodInvocationResult, AnnotationAccess

A representation of the invocation of a method that allows the behavior of the method to be advised: either by changing parameter values, or by changing the return value, or by catch or throwing different exceptions. Provides access to annotations on the advised method.

See Also:

MethodAdvice

Method Summary

Object	getInstance() The instance on which the method was originally invoked.
InstanceContext	getInstanceContext()
Method	getMethod() Returns the method being invoked.
Object	getParameter(int index) Returns the parameter at the given index.
MethodInvocation	proceed() Proceed with the method invocation, either chaining into the next MethodAdvice added to the method, or ultimately into the actual method implementation.
MethodInvocation	setCheckedException(Exception exception) Sets the checked exception; this can be used to indicate failure for the method, or to cancel the thrown exception (by setting the exception to null).
MethodInvocation	setParameter(int index, Object newValue) Changes a parameter value.
MethodInvocation	setReturnValue(Object returnValue) Overrides the return value of the method.

Methods inherited from interface org.apache.tapestry5.plastic.MethodInvocationResult

didThrowCheckedException, getCheckedException, getReturnValue, rethrow

Methods inherited from interface org.apache.tapestry5.plastic.AnnotationAccess

getAnnotation, hasAnnotation

Method Detail

getInstance

Object getInstance()

The instance on which the method was originally invoked.

getInstanceContext

InstanceContext getInstanceContext()

proceed

MethodInvocation proceed()

Proceed with the method invocation, either chaining into the next MethodAdvice added to the method, or ultimately into the actual method implementation. The method may throw a checked exception, which will be caught and be reported as MethodInvocationResult.didThrowCheckedException().

Returns:

this method invocation, for a fluent API

setReturnValue

MethodInvocation setReturnValue(Object returnValue)

Overrides the return value of the method. The value provided will be cast to the actual return type (or, if the return type is a primitive value, the value will be cast to the corresponding wrapper type and then converted to a primitive).

Overriding the return value clears any checked exception.

Parameters:

returnValue -

Returns:

this method invocation, for a fluent API

Throws:

NullPointerException - if the method's return type is a primitive and null is provided

getParameter

Object getParameter(int index)

Returns the parameter at the given index. Primitive types will be wrapped as they are returned.

Parameters:

index - of parameter to access

Returns:

parameter value

setParameter

MethodInvocation setParameter(int index,
                              Object newValue)

Changes a parameter value. The value will be cast to the parameter's type. For primitive types, the value will be cast to the corresponding wrapper type.

Parameters:

index - index of parameter to modify

newValue - new value for parameter

Returns:

this method invocation, for a fluent API

setCheckedException

MethodInvocation setCheckedException(Exception exception)

Sets the checked exception; this can be used to indicate failure for the method, or to cancel the thrown exception (by setting the exception to null).

Parameters:

exception - new checked exception, or null

Returns:

this method invocation, for a fluent API

getMethod

Method getMethod()

Returns the method being invoked.