1、启动类介绍
二、代码分析
/**
* Main method, used for testing only.
*
* @param args Command line arguments to be processed
*/
public static void main(String args[]) {
if (daemon == null) {
daemon = new Bootstrap();
try {
daemon.init();
} catch (Throwable t) {
t.printStackTrace();
return;
}
}
try {
String command = "start";
if (args.length > 0) {
command = args[args.length - 1];
}
if (command.equals("startd")) {
args[0] = "start";
daemon.load(args);
daemon.start();
} else if (command.equals("stopd")) {
args[0] = "stop";
daemon.stop();
} else if (command.equals("start")) {
daemon.setAwait(true);
daemon.load(args);
daemon.start();
} else if (command.equals("stop")) {
daemon.stopServer(args);
} else {
log.warn("Bootstrap: command \"" + command + "\" does not exist.");
}
} catch (Throwable t) {
t.printStackTrace();
}
}
/**
* Initialize daemon.
*/
public void init()
throws Exception
{
// Set Catalina path
setCatalinaHome();
setCatalinaBase();
initClassLoaders();
Thread.currentThread().setContextClassLoader(catalinaLoader);
SecurityClassLoad.securityClassLoad(catalinaLoader);
// Load our startup class and call its process() method
if (log.isDebugEnabled())
log.debug("Loading startup class");
Class startupClass =
catalinaLoader.loadClass
("org.apache.catalina.startup.Catalina");
Object startupInstance = startupClass.newInstance();
// Set the shared extensions class loader
if (log.isDebugEnabled())
log.debug("Setting startup class properties");
String methodName = "setParentClassLoader";
Class paramTypes[] = new Class[1];
paramTypes[0] = Class.forName("java.lang.ClassLoader");
Object paramValues[] = new Object[1];
paramValues[0] = sharedLoader;
Method method =
startupInstance.getClass().getMethod(methodName, paramTypes);
method.invoke(startupInstance, paramValues);
catalinaDaemon = startupInstance;
}
init方法总结:
init方法总计做了6件主要的事情
设置了系统变量CATALINA_HOME。
设置了系统变量CATALINA_BASE。
创建了3个类加载器commonloader,catalinaLoader,sharedLoader。
将当前启动线程的类加载器设置为catalinaLoader。
创建类Catalina的实例,并且调用setParentClassLoader方法,将Catalina类的父类加载器设置为catalinaLoader。
将第五条创建的Catalina类实例赋值给catalinaDaemon变量。