/*
* Copyright (c) 2002-2012 Alibaba Group Holding Limited.
* 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 com.alibaba.citrus.service.moduleloader.impl;
import static com.alibaba.citrus.util.Assert.*;
import static com.alibaba.citrus.util.CollectionUtil.*;
import java.util.Map;
import java.util.Set;
import com.alibaba.citrus.service.AbstractService;
import com.alibaba.citrus.service.configuration.ProductionModeAware;
import com.alibaba.citrus.service.moduleloader.Module;
import com.alibaba.citrus.service.moduleloader.ModuleAdapterFactory;
import com.alibaba.citrus.service.moduleloader.ModuleFactory;
import com.alibaba.citrus.service.moduleloader.ModuleLoaderException;
import com.alibaba.citrus.service.moduleloader.ModuleLoaderService;
import com.alibaba.citrus.service.moduleloader.ModuleNotFoundException;
import com.alibaba.citrus.service.moduleloader.UnadaptableModuleException;
import com.alibaba.citrus.util.ToStringBuilder;
import com.alibaba.citrus.util.ToStringBuilder.MapBuilder;
/**
* 实现<code>ModuleLoaderService</code>。
*
* @author Michael Zhou
*/
public class ModuleLoaderServiceImpl extends AbstractService<ModuleLoaderService> implements ModuleLoaderService,
ProductionModeAware {
private Map<ModuleKey, Module> moduleCache = createConcurrentHashMap();
private boolean productionMode = true;
private Boolean cacheEnabled;
private ModuleFactory[] factories;
private ModuleAdapterFactory[] adapters;
public void setFactories(ModuleFactory[] factories) {
this.factories = factories;
}
public void setAdapters(ModuleAdapterFactory[] adapters) {
this.adapters = adapters;
}
public Boolean isCacheEnabled() {
return cacheEnabled;
}
public void setCacheEnabled(Boolean cacheEnabled) {
this.cacheEnabled = cacheEnabled;
}
public boolean isProductionMode() {
return productionMode;
}
public void setProductionMode(boolean productionMode) {
this.productionMode = productionMode;
}
@Override
protected void init() {
assertNotNull(factories, "factories");
assertNotNull(adapters, "adapters");
if (cacheEnabled == null) {
cacheEnabled = productionMode; // 如果未指定cacheEnabled，则默认当productionMode时，打开cache。
}
getLogger().debug("Initialized {}", this);
}
public Set<String> getModuleTypes() {
Set<String> types = createTreeSet();
for (ModuleFactory factory : factories) {
types.addAll(factory.getModuleTypes());
}
return types;
}
public Set<String> getModuleNames(String moduleType) {
Set<String> names = createTreeSet();
for (ModuleFactory factory : factories) {
names.addAll(factory.getModuleNames(moduleType));
}
return names;
}
public Module getModule(String moduleType, String moduleName)
throws ModuleLoaderException, ModuleNotFoundException {
Module module = getModuleQuiet(moduleType, moduleName);
if (module == null) {
throw new ModuleNotFoundException("Module not found: type=" + moduleType + ", name=" + moduleName);
}
return module;
}
public Module getModuleQuiet(String moduleType, String moduleName) throws ModuleLoaderException {
ModuleKey moduleKey = new ModuleKey(moduleType, moduleName);
moduleType = moduleKey.getModuleType();
moduleName = moduleKey.getModuleName();
// 先检查cache
if (cacheEnabled) {
Module module = moduleCache.get(moduleKey);
if (module != null) {
return module;
}
}
// 从factory中装载
Object moduleObject = null;
Module module = null;
for (ModuleFactory factory : factories) {
moduleObject = factory.getModule(moduleType, moduleName);
if (moduleObject != null) {
break;
}
}
// 通过适配器转换接口
if (moduleObject != null) {
if (moduleObject instanceof Module) {
module = (Module) moduleObject; // 假如moduleObject直接实现了接口
} else {
for (ModuleAdapterFactory adapter : adapters) {
module = adapter.adapt(moduleType, moduleName, moduleObject);
if (module != null) {
break;
}
}
}
}
if (module == null) {
if (moduleObject != null) {
throw new UnadaptableModuleException("Could not adapt object to module: type=" + moduleType + ", name="
+ moduleName + ", class=" + moduleObject.getClass());
}
}
// 保存到cache。
if (cacheEnabled && module != null) {
moduleCache.put(moduleKey, module);
}
return module;
}
@Override
public String toString() {
MapBuilder mb = new MapBuilder();
mb.append("factories", factories);
mb.append("adapters", adapters);
return new ToStringBuilder().append(getBeanDescription()).append(mb).toString();
}
}