com.gargoylesoftware.base.gui

Class ReflectedAction

java.lang.Object

javax.swing.AbstractAction

com.gargoylesoftware.base.gui.ReflectedAction

All Implemented Interfaces:

java.awt.event.ActionListener, java.io.Serializable, java.lang.Cloneable, java.util.EventListener, javax.swing.Action

public class ReflectedAction
extends javax.swing.AbstractAction

A swing "action" that uses reflection to find and invoke a given target method.

ReflectedAction is a Swing "action" that uses reflection to call a specific target method when the action is fired. Actions are often implemented using inner classes which can be very inefficient in terms of performance and deployment size. This action is a tiny bit slower when it is actually fired but is smaller and generally faster otherwise due to the fact that those inner classes are no longer needed.

 Action searchAction = new ReflectedAction(this, "performSearch");
 

Version:

$Revision: 1.4 $

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
private java.lang.String	methodName_
private java.lang.Object	object_
private static long	serialVersionUID

Fields inherited from class javax.swing.AbstractAction

changeSupport, enabled

Fields inherited from interface javax.swing.Action

ACCELERATOR_KEY, ACTION_COMMAND_KEY, DEFAULT, DISPLAYED_MNEMONIC_INDEX_KEY, LARGE_ICON_KEY, LONG_DESCRIPTION, MNEMONIC_KEY, NAME, SELECTED_KEY, SHORT_DESCRIPTION, SMALL_ICON

Constructor Summary

Constructors

Constructor and Description
ReflectedAction(java.lang.Object object, java.lang.String methodName) Create a reflected action with an object and the name of the method that will be invoked on that object when the action is fired.

Method Summary

Modifier and Type	Method and Description
void	actionPerformed(java.awt.event.ActionEvent event) The action has been fired so now we use reflection to invoke the method that was specified previously.
protected void	assertNotNull(java.lang.String fieldName, java.lang.Object object) Throw an exception if the specified object is null
protected void	exceptionThrown(java.lang.Exception exception) Callback that will be invoked if an exception is thrown during the reflected method call.
private java.lang.reflect.Method	findMethodOnObject(java.lang.Object object, java.lang.String methodName) Return the Method object that corresponds to the specified method name.

Methods inherited from class javax.swing.AbstractAction

addPropertyChangeListener, clone, firePropertyChange, getKeys, getPropertyChangeListeners, getValue, isEnabled, putValue, removePropertyChangeListener, setEnabled

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

serialVersionUID

private static final long serialVersionUID

See Also:

Constant Field Values

object_

private final java.lang.Object object_

methodName_

private final java.lang.String methodName_

Constructor Detail

ReflectedAction

public ReflectedAction(java.lang.Object object,
                       java.lang.String methodName)
                throws java.lang.IllegalArgumentException

Create a reflected action with an object and the name of the method that will be invoked on that object when the action is fired.

Parameters:

object - The object upon which we will invoke a method when the action is fired

methodName - The name of the method that we will invoke. This method must take either no parameters or one parameter which is an ActionEvent.

Throws:

java.lang.IllegalArgumentException - if there are no matching methods.

Method Detail

actionPerformed

public void actionPerformed(java.awt.event.ActionEvent event)

The action has been fired so now we use reflection to invoke the method that was specified previously.

Parameters:

event - The ActionEvent

findMethodOnObject

private java.lang.reflect.Method findMethodOnObject(java.lang.Object object,
                                                    java.lang.String methodName)

Return the Method object that corresponds to the specified method name. The method may take either no arguments or may take an ActionEvent.

Parameters:

object - The object that contains the method

methodName - The name of the method that we're looking for

Returns:

The method that matches the specified name.

Throws:

java.lang.IllegalArgumentException - If there aren't any methods that match.

java.lang.SecurityException - If we do not have access to this method.

exceptionThrown

protected void exceptionThrown(java.lang.Exception exception)

Callback that will be invoked if an exception is thrown during the reflected method call.

Override this to provide custom error handling. Default behaviour is to print a stack trace.

Parameters:

exception - The exception

assertNotNull

protected final void assertNotNull(java.lang.String fieldName,
                                   java.lang.Object object)

Throw an exception if the specified object is null

Parameters:

fieldName - The name of the paremeter we are checking

object - The value of the parameter we are checking