ComponentContainer load 流程
/*
1 : 前言
ContainerLoader.java文件首先把ofbiz -
container.xml定义的container读入到了.ContainerConfig
2 : 加载
*/
private Container loadContainer(String classname, String configFileLocation) throws
StartupException {
// load the component container class
ClassLoader loader = Thread.currentThread().getContextClassLoader();
if (loader == null) {
Debug.logWarning("Unable to get context classloader; using system", module);
loader = ClassLoader.getSystemClassLoader();
}
Class componentClass = null;
try {
componentClass = loader.loadClass(classname);
}
catch (ClassNotFoundException e) {
throw new StartupException("Cannot locate container class", e);
}
if (componentClass == null) {
throw new StartupException("Component container class not loaded");
}
Container componentObj = null;
try {
componentObj = (Container) componentClass.newInstance();
////通过classname生成实例
}
catch (InstantiationException e) {
throw new StartupException(e);
}
catch (IllegalAccessException e) {
throw new StartupException(e);
}
catch (ClassCastException e) {
throw new StartupException(e);
}
if (componentObj == null) {
throw new StartupException(
"Unable to create instance of component container");
}
try {
componentObj.start(configFileLocation); //容器初始化
}
catch (ContainerException e) {
throw new StartupException(e);
}
return componentObj;
}
3 : ComponentContainer加载
ComponentContainer.java类
/*
loadConfig参数是Components配置文件名,如果没有，将自动取系统自定义的
Component-Load.xml,如果需要定义，可以
<container
name="component-container" class="org.ofbiz.base.container.ComponentContainer">
<propterty name="load-config" value="xxx.xml"/>
</container>
updateClasspath:加载完后是否重新设置classpath
*/
public synchronized void loadComponents(String loaderConfig,
boolean updateClasspath) throws
AlreadyLoadedException, ComponentException {
// 设置load list,如果失败，抛出Already Loaded Exception
if (loadedComponents == null) {
loadedComponents = new LinkedList(); //用Linklist保存将要加载的Components
}
else {
throw new AlreadyLoadedException("Components already loaded, cannot start");
}
/*
ComponentLoader将读取Component-Load.xml, 存储所有的组件,
components存储的实例名是ComponentDef,它对应于:
<load-component component-location="${ofbiz.home}/components/minerva"/>
*/
List components = ComponentLoaderConfig.getComponentsToLoad(loaderConfig);
/*
加载每一个Components
*/
if (components != null) {
Iterator ci = components.iterator();
while (ci.hasNext()) {
ComponentLoaderConfig.ComponentDef def = (ComponentLoaderConfig.
ComponentDef) ci.next();
if (def.type == ComponentLoaderConfig.SINGLE_COMPONENT) {
ComponentConfig config = null;
try {
/*在这里将要读取每个组件下的 ofbiz-component.xml文件
比如：
/components/minerva/ofbiz-component.xml
/components/entity/ofbiz-component.xml
ComponentConfig用一个静态的HashMap存储系统中所在的Component.
每个ComponentConfig对应于一个ofbiz-component.xml文件.
*/
config = ComponentConfig.getComponentConfig(def.name, def.location);
if (UtilValidate.isEmpty(def.name)) {
def.name = config.getGlobalName();
}
}
catch (ComponentException e) {
Debug.logError("Cannot load component : " + def.name + " @ " +
def.location + " : " + e.getMessage(), module);
}
if (config == null) {
Debug.logError("Cannot load component : " + def.name + " @ " +
def.location, module);
}
else {
/*
主要作要就是把当前Components用到的jar放入classpath中
*/
loadComponent(config);
}
}
else if (def.type == ComponentLoaderConfig.COMPONENT_DIRECTORY) {
loadComponentDirectory(def.location);
}
}
}
// set the new classloader/classpath on the current thread
if (updateClasspath) {
System.setProperty("java.class.path", classPath.toString());
ClassLoader cl = classPath.getClassLoader();
Thread.currentThread().setContextClassLoader(cl);
}
Debug.logInfo("All components loaded", module);
}
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