/**
* JBoss, Home of Professional Open Source
* Copyright 2011, Red Hat, Inc. and individual contributors
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.arquillian.ajocado.command;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.util.Collections;
import java.util.HashSet;
import java.util.LinkedHashMap;
import java.util.LinkedHashSet;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import com.thoughtworks.selenium.CommandProcessor;
/**
* <p>
* The proxy for command processor which instead of direct executing of given command triggers logic of all associated
* interceptors.
* </p>
*
* @author <a href="mailto:lfryc@redhat.com">Lukas Fryc</a>
* @version $Revision$
*/
public final class CommandInterceptorProxyImpl implements CommandInterceptorProxy, java.lang.reflect.InvocationHandler {
/**
* The list of intercepted method names
*/
@SuppressWarnings("serial")
private Set<String> interceptedMethods = Collections.unmodifiableSet(new HashSet<String>() {
{
add("doCommand");
add("getString");
add("getBoolean");
add("getNumber");
add("getStringArray");
add("getBooleanArray");
add("getNumberArray");
}
});
private CommandProcessor commandProcessor;
/**
* The map of associated interceptors with keys of it's class
*/
private Map<Class<? extends CommandInterceptor>, CommandInterceptor> interceptors = new LinkedHashMap<Class<? extends CommandInterceptor>, CommandInterceptor>();
/**
* Constructs new proxy with associated command processor
*
* @param commandProcessor to associate with this proxy
*/
public CommandInterceptorProxyImpl(CommandProcessor commandProcessor) {
this.commandProcessor = commandProcessor;
}
/**
* Returns the command processor proxied with functionality of all associated interceptors.
*
* @return the command processor proxied with functionality of all associated interceptors
*/
public CommandProcessor getCommandProcessorProxy() {
return (CommandProcessor) Proxy.newProxyInstance(commandProcessor.getClass().getClassLoader(), commandProcessor
.getClass().getInterfaces(), this);
}
/**
* <p>
* Proxies all the request on associated command processor.
* </p>
*
* <p>
* In case of {@link CommandProcessor#doCommand(String, String[])} method, it also executes all associated interceptors
* before performing the actual invocation of method.
* </p>
*/
@Override
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
Object result;
try {
if (interceptedMethods.contains(method.getName())) {
String commandName = (String) args[0];
String[] arguments = (String[]) args[1];
CommandContextImpl context = new CommandContextImpl(commandName, arguments, commandProcessor, method,
interceptors.values());
try {
result = context.invoke();
} catch (CommandInterceptorException e) {
throw new IllegalStateException("There was at least one interceptor which didn't call invoke()");
} catch (Exception e) {
throw new InvocationTargetException(e);
}
} else {
result = method.invoke(commandProcessor, args);
}
} catch (InvocationTargetException e) {
throw e.getCause();
} catch (Exception e) {
throw new RuntimeException("unexpected invocation exception: " + e.getMessage());
}
return result;
}
/**
* Registers the interceptor, only one interceptor can be registered for given class of interceptor.
*
* @param interceptor the interceptor implementation
*/
@Override
public void registerInterceptor(CommandInterceptor interceptor) {
interceptors.put(interceptor.getClass(), interceptor);
}
/**
* Removes and returns the interceptor instance, or null, if such instance isn't registered.
*
* @param interceptor the instance of interceptor to remove
* @return removed interceptor or null, if such interceptor ins't registered
*/
@Override
public CommandInterceptor unregisterInterceptor(CommandInterceptor interceptor) {
Class<? extends CommandInterceptor> typeToRemove = null;
for (Entry<Class<? extends CommandInterceptor>, CommandInterceptor> entry : interceptors.entrySet()) {
if (entry.getValue().equals(interceptor)) {
typeToRemove = entry.getKey();
break;
}
}
return interceptors.remove(typeToRemove);
}
/**
* Removes and returns all associated interceptors which of given type.
*
* @param type of interceptors which we want to unregister from this command processor
* @return the removed interceptors
*/
@Override
public Set<CommandInterceptor> unregisterInterceptorType(Class<? extends CommandInterceptor> type) {
Set<Class<? extends CommandInterceptor>> typesToRemove = new LinkedHashSet<Class<? extends CommandInterceptor>>();
for (Class<? extends CommandInterceptor> entryType : interceptors.keySet()) {
if (entryType.isInstance(type)) {
typesToRemove.add(entryType);
}
}
Set<CommandInterceptor> removedInterceptors = new LinkedHashSet<CommandInterceptor>();
for (Class<? extends CommandInterceptor> typeToRemove : typesToRemove) {
removedInterceptors.add(interceptors.remove(typeToRemove));
}
return removedInterceptors;
}
/**
* Creates immutable copy of this command processor with all interceptors registered.
*
* @return the immutable copy of this command processor
*/
public CommandInterceptorProxyImpl immutableCopy() {
CommandInterceptorProxyImpl copy = new CommandInterceptorProxyImpl(commandProcessor);
copy.interceptors.putAll(this.interceptors);
return copy;
}
}