com.logicbus.models.servant.ServantManager Maven / Gradle / Ivy
package com.logicbus.models.servant;
import java.io.InputStream;
import java.util.Vector;
import org.apache.log4j.LogManager;
import org.apache.log4j.Logger;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import com.anysoft.util.Factory;
import com.anysoft.util.IOTools;
import com.anysoft.util.Settings;
import com.anysoft.util.XmlTools;
import com.anysoft.util.resource.ResourceFactory;
import com.logicbus.models.catalog.CatalogNode;
import com.logicbus.models.catalog.Path;
/**
* 服务规格管理器
*
*
* 服务规格管理器负责从服务目录中读取服务规格信息,可支持一到多个服务目录.配置文件地址可以从web.xml或者全局参数中读取，参数包括：
*
* - master.servant.config 配置文件URL地址,缺省为：java:///com/logicbus/models/servant/default.xml
* - secondary.servant.config 配置文件备用URL地址,缺省为:java:///com/logicbus/models/servant/default.xml
*
* 缺省的配置文件内容如下:
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
*
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
*
*
* 由于{@link ServantManager}在查找服务时是一个一个服务目录查找的,因此配置文件中的服务目录次序就很重要,如果配置在前面,将优先被搜索到.
* 例如配置了服务目录A和服务目录B，而A和B中都包含了服务/demo/logicbus/Helloworld,由于A配置在前面，将永远搜索到A提供的/demo/logicbus/Helloworld，
* 而B中提供的/demo/logicbus/Helloworld服务则永远不会被调用.
*
* @author duanyy
*
*/
public class ServantManager {
/**
* 全局唯一实例
*/
protected static ServantManager instance = null;
/**
* a logger of log4j
*/
protected static Logger logger = LogManager.getLogger(ServantManager.class);
/**
* 服务目录列表
*/
protected Vector catalogs = new Vector();
/**
* 查询指定服务的服务规格
* @param id 服务ID
* @return 服务规格
*/
public ServiceDescription get(Path id){
for (int i = 0 ; i < catalogs.size() ; i ++){
ServantCatalog __catalog = catalogs.elementAt(i);
if (__catalog == null){
continue;
}
ServiceDescription sd = __catalog.findService(id);
if (sd != null){
return sd;
}
}
return null;
}
/**
* 按路径得到目录节点
*
* @param path 目录节点的路径
* @return 目录节点
*/
public CatalogNode getCatalogNode(Path path){
for (int i = 0 ; i < catalogs.size() ; i ++){
ServantCatalog __catalog = catalogs.elementAt(i);
if (__catalog == null){
continue;
}
CatalogNode found = __catalog.getChildByPath(null, path);
if (found != null)
return found;
}
return null;
}
/**
* Class Loader
*/
protected ClassLoader classLoader = null;
/**
* Constructor
*
*/
public ServantManager(){
Document doc = null;
Settings profile = Settings.get();
String configFile = profile.GetValue("servant.config.master",
"java:///com/logicbus/models/servant/servantcatalog.default.xml#com.logicbus.backend.server.LogicBusApp");
String secondaryFile = profile.GetValue("servant.config.secondary",
"java:///com/logicbus/models/servant/servantcatalog.default.xml#com.logicbus.backend.server.LogicBusApp");
ResourceFactory rm = (ResourceFactory) profile.get("ResourceFactory");
if (null == rm){
rm = new ResourceFactory();
}
classLoader = (ClassLoader) profile.get("classLoader");
if (classLoader == null){
classLoader = ServantManager.class.getClassLoader();
}
InputStream in = null;
try {
in = rm.load(configFile,secondaryFile, null);
doc = XmlTools.loadFromInputStream(in);
loadConfig(doc);
} catch (Exception ex){
logger.error("Error occurs when load xml file,source=" + configFile, ex);
}finally {
IOTools.closeStream(in);
}
}
/**
* 读取配置信息
*
*
* 在{@link #ServantManager()}中调用.
*
* @param doc 配置文档
*
*/
private void loadConfig(Document doc) {
if (doc == null) return;
Element root = doc.getDocumentElement();
Factory factory = new Factory();
NodeList children = root.getChildNodes();
for (int i = 0; i < children.getLength() ; i++){
Node item = children.item(i);
if (item.getNodeType() != Node.ELEMENT_NODE){
continue;
}
Element e = (Element)item;
if (!e.getNodeName().equals("catalog")){
continue;
}
try {
ServantCatalog servantCatalog = factory.newInstance(e, Settings.get(), "module");
if (servantCatalog != null){
catalogs.add(servantCatalog);
}
}catch (Exception ex){
logger.error("Can not create instance of ServantCatalog.", ex);
}
}
}
/**
* 获得服务目录列表
*
* @return 服务目录列表
*/
public ServantCatalog[] getServantCatalog(){
return (ServantCatalog[]) catalogs.toArray(new ServantCatalog[0]);
}
/**
* 获取唯一实例
* @return 唯一实例
*/
public static ServantManager get(){
if (instance == null){
synchronized (ServantManager.class){
if (instance == null){
instance = new ServantManager();
}
}
}
return instance;
}
/**
* 增加监听器,在服务信息变更的时候触发
* @param watcher
*/
public void addWatcher(ServiceDescriptionWatcher watcher){
for (ServantCatalog catalog:catalogs){
if (catalog != null){
catalog.addWatcher(watcher);
}
}
}
}