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An application to get controlled access to private members of Java classes

There is a newer version: 0.2.7

package com.almondtools.picklock;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.util.HashMap;
import java.util.Map;

/**
 * ObjectAccess is a Decorator for any object that should get a new public interface. Usage:
 * 
 * InterfaceOfTheDecorator unlocked = ObjectAccess.unlock(object).features(InterfaceOfTheDecorator.class);
 * 
 * 
After that the variable unlocked contains an object of type InterfaceOfTheDecorator, where each method is mapped according to the picklock conventions:
 * 
 *  * 
 * * 
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 *   
 Method Maps to 
void setProperty([sometype] t) void setProperty([sometype] t) if exists
property = t; if there is a property [sometype] property;
[sometype] getProperty() [sometype] getProperty() if exists
return property; if there is a property [sometype] property;
[booleantype] isProperty() [booleantype] getProperty() if exists
return property; if there is a property [booleantype] property;
[return type] methodname([signature]) [return type] methodname([signature]) 
 * 
 * @author Stefan Mandel
 */
public class ObjectAccess extends InvocationResolver implements InvocationHandler {

	private Map methods;
	private Object object;

	public ObjectAccess(Object object) {
		super(object.getClass());
		this.methods = new HashMap();
		this.object = object;
	}
	
	public Object getObject() {
		return object;
	}

	/**
	 * wraps the given object. The result of this method will be decoratable with the new interface
	 * 
	 * @param type
	 *            the class to unlock/decorate
	 * @return the wrapped object
	 */
	public static ObjectAccess unlock(Object object) {
		return new ObjectAccess(object);
	}

	/**
	 * wraps the given class. The result of this method is a {@link ObjectSnoop} object which enables the user to check if a wrapped object (of the given class)
	 * could be target of a mapping from a specific interface. Note that a class (not an object) is wrapped, but the result will check the instance interface of this class
	 * (all non-static methods without constructors) not the static interface. static interfaces could be checked with {@link com.almondtools.picklock.ClassAccess#check(Class)}. 
	 * 
	 * @param type
	 *            the target class to check
	 * @return the wrapped class
	 */
	public static ObjectSnoop check(Class clazz) {
		return new ObjectSnoop(clazz);
	}

	/**
	 * maps the given interface to the wrapped object
	 * 
	 * @param interfaceClass
	 *            the given interface class (defining the type of the result)
	 * @return an object of the type of interfaceClass (mapped to the members of the wrapped object)
	 * @throws NoSuchMethodException
	 *             if a method of the interface class could not be mapped according to the upper rules
	 */
	@SuppressWarnings("unchecked")
	public  T features(Class interfaceClass) throws NoSuchMethodException {
		for (Method method : interfaceClass.getDeclaredMethods()) {
			methods.put(method, findInvocationHandler(method));
		}
		return (T) Proxy.newProxyInstance(interfaceClass.getClassLoader(), new Class[] { interfaceClass }, this);
	}

	@Override
	public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
		MethodInvocationHandler handler = methods.get(method);
		return handler.invoke(object, args);
	}

}

Method	Maps to
`void setProperty([sometype] t)`	`void setProperty([sometype] t)`	if exists
	`property = t;`	if there is a property `[sometype] property;`
`[sometype] getProperty()`	`[sometype] getProperty()`	if exists
	`return property;`	if there is a property `[sometype] property;`
`[booleantype] isProperty()`	`[booleantype] getProperty()`	if exists
	`return property;`	if there is a property `[booleantype] property;`
`[return type] methodname([signature])`	`[return type] methodname([signature])`