net.drgnome.nbtlib

Class ClassProxy

java.lang.Object

net.drgnome.nbtlib.ClassProxy

public class ClassProxy
extends Object

A util which allows you to create class proxies.

This means if you specify a class A, then a class B which extends A will be created and, depending on the given MethodFilter, some or all non-static non-final methods which are public or protected will be overridden and dispatched to a provided InvocationHandler.

Examples:

Since:

0.3

Method Summary

Methods

Modifier and Type	Method and Description
static Object	callSuper(Object proxy, Method method, Object... args) Calls the method that has been overridden by a proxy method.
static Class	getClass(Class superClass, boolean createIfNotExists) Creates a proxy class for a given super class.
static Class	getClass(Class superClass, MethodFilter filter, boolean createIfNotExists) Creates a proxy class for a given super class.
static boolean	isProxy(Class clazz) Returns true if the given Class object is a proxy class generated by the ClassProxy class.
static <T> T	newInstance(Class<T> superClass, InvocationHandler handler, Class[] paramTypes, Object... params) Creates a proxy class for a given super class and instantiates it.
static <T> T	newInstance(Class<T> superClass, MethodFilter filter, InvocationHandler handler, Class[] paramTypes, Object... params) Creates a proxy class for a given super class and instantiates it.

Methods inherited from class java.lang.Object

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

Method Detail

isProxy

public static boolean isProxy(Class clazz)

Returns true if the given Class object is a proxy class generated by the ClassProxy class.

Parameters:

clazz - The Class object to be checked.

Returns:

true if the given Class object is a proxy class, false otherwise.

callSuper

public static Object callSuper(Object proxy,
               Method method,
               Object... args)
                        throws Throwable

Calls the method that has been overridden by a proxy method.

Parameters:

proxy - The proxy instance.

method - The method you want to call.

args - The argument to pass to the method.

Returns:

Whatever the super method returns.

Throws:

NoSuchMethodException - If the super method cannot be found.

SecurityException - If the super method cannot be accessed.

Throwable - If the super method throws anything.

newInstance

public static <T> T newInstance(Class<T> superClass,
                InvocationHandler handler,
                Class[] paramTypes,
                Object... params)
                     throws IllegalArgumentException

Creates a proxy class for a given super class and instantiates it.

This basically just calls newInstance(superClass, null, handler, paramTypes, params).

Parameters:

superClass - The class on which you wish to create a proxy.

handler - The InvocationHandler to which public and protected method calls will be redirected.

paramTypes - An array of Classes to identify the constructor of the super class you wish to invoke.

params - An array or arguments to pass to the constructor of the super class.

Returns:

An new proxy instance.

Throws:

IllegalArgumentException - If the proxy class has not yet been created: See getClass().

newInstance

public static <T> T newInstance(Class<T> superClass,
                MethodFilter filter,
                InvocationHandler handler,
                Class[] paramTypes,
                Object... params)
                     throws IllegalArgumentException

Creates a proxy class for a given super class and instantiates it.

Parameters:

superClass - The class on which you wish to create a proxy.

filter - The MethodFilter to use on superClass.

handler - The InvocationHandler to which public and protected method calls will be redirected.

paramTypes - An array of Classes to identify the constructor of the super class you wish to invoke.

params - An array or arguments to pass to the constructor of the super class.

Returns:

An new proxy instance.

Throws:

IllegalArgumentException - If the proxy class has not yet been created: See getClass().

getClass

public static Class getClass(Class superClass,
             boolean createIfNotExists)
                      throws IllegalArgumentException

Creates a proxy class for a given super class.

Creates a new Class which extends a given super class which redirects all calls to public and protected methods which are non-final and non-static to a given InvocationHandler.
Abstract methods will be defined and redirected to the InvocationHandler as well.
For every public and protected constructor the super class has, this class will have the same constructor with an InvocationHandler as additional first parameter.

Parameters:

superClass - The class on which you wish to create a proxy. Has to be public and not final, primitive, an array or an interface.

createIfNotExists - Whether or not to create a proxy class if none exists.

Returns:

The new class. May be null if createIfNotExists == false.

Throws:

IllegalArgumentException - If createIfNotExists is true, the class does not exist yet and no valid bytecode can be generated.

getClass

public static Class getClass(Class superClass,
             MethodFilter filter,
             boolean createIfNotExists)
                      throws IllegalArgumentException

Creates a proxy class for a given super class.

Creates a new Class which extends a given super class which redirects all calls to public and protected methods which are non-final and non-static, on which filter.filterMethod() returns true, to a given InvocationHandler.
Abstract methods will be defined and redirected to the InvocationHandler as well.
For every public and protected constructor the super class has, this class will have the same constructor with an InvocationHandler as additional first parameter.

Parameters:

superClass - The class on which you wish to create a proxy. Has to be public and not final, primitive, an array or an interface.

filter - The MethodFilter to use on superClass.

createIfNotExists - Whether or not to create a proxy class if none exists.

Returns:

The new class. May be null if createIfNotExists == false.

Throws:

IllegalArgumentException - If createIfNotExists is true, the class does not exist yet and no valid bytecode can be generated.