/*
* Copyright 1999-2011 Alibaba Group.
*
* 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 com.alibaba.dubbo.rpc.cluster.support;
import java.util.ArrayList;
import java.util.List;
import com.alibaba.dubbo.common.Constants;
import com.alibaba.dubbo.common.ExtensionLoader;
import com.alibaba.dubbo.common.URL;
import com.alibaba.dubbo.rpc.Invocation;
import com.alibaba.dubbo.rpc.Invoker;
import com.alibaba.dubbo.rpc.RpcException;
import com.alibaba.dubbo.rpc.cluster.Directory;
import com.alibaba.dubbo.rpc.cluster.Router;
import com.alibaba.dubbo.rpc.cluster.RouterFactory;
/**
* 增加router的Directory
* @author chao.liuc
*/
public abstract class AbstractDirectory<T> implements Directory<T> {
private final URL url ;
protected volatile boolean destroyed = false;
private List<Router> routers = new ArrayList<Router>();
public AbstractDirectory(URL url) {
this(url, null);
}
public AbstractDirectory(URL url, List<Router> routers) {
if (url == null)
throw new IllegalArgumentException("url == null");
if (routers == null){
routers = new ArrayList<Router>();
}
this.url = url;
String routerkey = url.getParameter(Constants.ROUTER_KEY);
if (routerkey != null && routerkey.length()>0 ){
RouterFactory routerFactory = ExtensionLoader.getExtensionLoader(RouterFactory.class).getExtension(routerkey);
routers.add(routerFactory.getRouter(url));
}
if (routers != null) {
setRouters(routers);
}
}
public List<Invoker<T>> list(Invocation invocation) throws RpcException {
if (destroyed){
throw new RpcException("Directory already destroyed .url: "+ getUrl());
}
List<Invoker<T>> invokers = doList(invocation);
for (Router router: routers){
invokers = router.route(invokers, invocation);
}
return invokers;
}
public URL getUrl() {
return url;
}
public List<Router> getRouters(){
return routers;
}
protected abstract List<Invoker<T>> doList(Invocation invocation) throws RpcException ;
protected void setRouters(List<Router> r){
routers = r;
}
public void destroy(){
destroyed = true;
}
}