/***
* Copyright (c) 2009 Caelum - www.caelum.com.br/opensource All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy of
* the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
*/
package br.com.caelum.vraptor.view;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import javax.servlet.ServletContext;
import net.vidageek.mirror.dsl.Mirror;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import br.com.caelum.vraptor.http.route.Router;
import com.google.common.collect.ForwardingMap;
/**
* View helper for generating uris
* @author Lucas Cavalcanti
* @since 3.4.0
*
*/
public class LinkToHandler extends ForwardingMap<Class<?>, Object> {
private static final Logger logger = LoggerFactory.getLogger(LinkToHandler.class);
private final ServletContext context;
private final Router router;
public LinkToHandler(ServletContext context, Router router) {
this.context = context;
this.router = router;
}
public void start() {
logger.info("Registering linkTo component");
context.setAttribute("linkTo", this);
}
@Override
protected Map<Class<?>, Object> delegate() {
return Collections.emptyMap();
}
@Override
public LinkMethod get(Object key) {
return new LinkMethod((Class<?>) key);
}
class LinkMethod extends ForwardingMap<String, Linker> {
private final Class<?> controller;
public LinkMethod(Class<?> controller) {
this.controller = controller;
}
@Override
protected Map<String, Linker> delegate() {
return Collections.emptyMap();
}
@Override
public Linker get(Object key) {
return new Linker(controller, key.toString());
}
@Override
public String toString() {
throw new IllegalArgumentException("uncomplete linkTo[" + controller.getSimpleName() + "]. You must specify the method.");
}
}
class Linker extends ForwardingMap<Object, Linker> {
private final List<Object> args;
private final String methodName;
private final Class<?> controller;
public Linker(Class<?> controller, String methodName) {
this(controller, methodName, new ArrayList<Object>());
}
public Linker(Class<?> controller, String methodName, List<Object> args) {
this.controller = controller;
this.methodName = methodName;
this.args = args;
}
@Override
public Linker get(Object key) {
List<Object> newArgs = new ArrayList<Object>(args);
newArgs.add(key);
return new Linker(controller, methodName, newArgs);
}
@Override
protected Map<Object, Linker> delegate() {
return Collections.emptyMap();
}
@Override
public String toString() {
Method method = null;
if(getMethodsAmountWithSameName() > 1 && args.size() > 0) {
method = new Mirror().on(controller).reflect().method(methodName).withArgs(getClasses(args));
} else {
method = findMethodWithName(controller, methodName);
}
if(method == null)
throw new IllegalArgumentException("There are no methods on " + controller + " named " + methodName);
return context.getContextPath() + router.urlFor(controller, method, args.toArray());
}
private Method findMethodWithName(Class<?> type, String name) {
for (Method method : type.getDeclaredMethods()) {
if (!method.isBridge() && method.getName().equals(name)) {
return method;
}
}
if (type.getSuperclass().equals(Object.class)) {
return null;
}
return findMethodWithName(type.getSuperclass(), name);
}
private int getMethodsAmountWithSameName() {
int amount = 0;
for (Method method : controller.getDeclaredMethods()) {
if (!method.isBridge() && method.getName().equals(methodName)) {
amount++;
}
}
return amount;
}
private Class<?>[] getClasses(List<Object> params) {
Class<?>[] classes = new Class<?>[params.size()];
for(int i = 0; i < params.size(); i ++) {
classes[i] = params.get(i).getClass();
}
return classes;
}
}
}