[Tomcat6.0源码]组件的初始化

1.Bootstrap.main()做的几件事：

1）daemon.init();创建Catalina对象

2）daemon.load(args);调用Catalina.load();通过解析server.xml对相关组件的实例化和初始化

3）daemon.start();调用Catalina.start()依次启动各组件

前面已经了解Catalina.load()用Digester实例化各组件的过程。接着看看各组件的初始化：

if (getServer() instanceof Lifecycle) {
try {
getServer().initialize();
} catch (LifecycleException e) {
if (Boolean.getBoolean("org.apache.catalina.startup.EXIT_ON_INIT_FAILURE"))
throw new java.lang.Error(e);
else
log.error("Catalina.start", e);

}
}

2.getServer().initialize();调用StandardServer.initialize():

/**
* Invoke a pre-startup initialization. This is used to allow connectors
* to bind to restricted ports under Unix operating environments.
*/
public void initialize()
throws LifecycleException
{
if (initialized) {
log.info(sm.getString("standardServer.initialize.initialized"));
return;
}
lifecycle.fireLifecycleEvent(INIT_EVENT, null);
initialized = true;

if( oname==null ) {
try {
oname=new ObjectName( "Catalina:type=Server");
Registry.getRegistry(null, null)
.registerComponent(this, oname, null );
} catch (Exception e) {
log.error("Error registering ",e);
}
}

// Register global String cache
try {
ObjectName oname2 =
new ObjectName(oname.getDomain() + ":type=StringCache");
Registry.getRegistry(null, null)
.registerComponent(new StringCache(), oname2, null );
} catch (Exception e) {
log.error("Error registering ",e);
}

// Initialize our defined Services
for (int i = 0; i < services.length; i++) {
services[i].initialize();
}
}

3.循环执行services[i].initialize();即调用与其相关的所有StandardService.initialize()：

/**
* Invoke a pre-startup initialization. This is used to allow connectors
* to bind to restricted ports under Unix operating environments.
*/
public void initialize()
throws LifecycleException
{
// Service shouldn't be used with embeded, so it doesn't matter
if (initialized) {
if(log.isInfoEnabled())
log.info(sm.getString("standardService.initialize.initialized"));
return;
}
initialized = true;

if( oname==null ) {
try {
// Hack - Server should be deprecated...
Container engine=this.getContainer();
domain=engine.getName();
oname=new ObjectName(domain + ":type=Service,serviceName="+name);
this.controller=oname;
Registry.getRegistry(null, null)
.registerComponent(this, oname, null);

Executor[] executors = findExecutors();
for (int i = 0; i < executors.length; i++) {
ObjectName executorObjectName =
new ObjectName(domain + ":type=Executor,name=" + executors[i].getName());
Registry.getRegistry(null, null)
.registerComponent(executors[i], executorObjectName, null);
}

} catch (Exception e) {
log.error(sm.getString("standardService.register.failed",domain),e);
}

}
if( server==null ) {
// Register with the server
// HACK: ServerFactory should be removed...

ServerFactory.getServer().addService(this);
}

// Initialize our defined Connectors
synchronized (connectors) {
for (int i = 0; i < connectors.length; i++) {
try {
connectors[i].initialize();
} catch (Exception e) {
String message = sm.getString(
"standardService.connector.initFailed",
connectors[i]);
log.error(message, e);

if (Boolean.getBoolean("org.apache.catalina.startup.EXIT_ON_INIT_FAILURE"))
throw new LifecycleException(message);
}
}
}
}

4.循环执行connectors[i].initialize();即调用与其相关的所有Connector.initialize()：

/**
* Initialize this connector (create ServerSocket here!)
*/
public void initialize()
throws LifecycleException
{
if (initialized) {
if(log.isInfoEnabled())
log.info(sm.getString("coyoteConnector.alreadyInitialized"));
return;
}

this.initialized = true;

if( oname == null && (container instanceof StandardEngine)) {
try {
// we are loaded directly, via API - and no name was given to us
StandardEngine cb=(StandardEngine)container;
oname = createObjectName(cb.getName(), "Connector");
Registry.getRegistry(null, null)
.registerComponent(this, oname, null);
controller=oname;
} catch (Exception e) {
log.error( "Error registering connector ", e);
}
if(log.isDebugEnabled())
log.debug("Creating name for connector " + oname);
}

// Initializa adapter
adapter = new CoyoteAdapter(this);
protocolHandler.setAdapter(adapter);

IntrospectionUtils.setProperty(protocolHandler, "jkHome",
System.getProperty("catalina.base"));

try {
protocolHandler.init();
} catch (Exception e) {
throw new LifecycleException
(sm.getString
("coyoteConnector.protocolHandlerInitializationFailed", e));
}
}

5.protocolHandler.init();调用Http11Protocol.init();

public void init() throws Exception {
endpoint.setName(getName());
endpoint.setHandler(cHandler);

// Verify the validity of the configured socket factory
try {
if (isSSLEnabled()) {
sslImplementation =
SSLImplementation.getInstance(sslImplementationName);
socketFactory = sslImplementation.getServerSocketFactory();
endpoint.setServerSocketFactory(socketFactory);
} else if (socketFactoryName != null) {
socketFactory = (ServerSocketFactory) Class.forName(socketFactoryName).newInstance();
endpoint.setServerSocketFactory(socketFactory);
}
} catch (Exception ex) {
log.error(sm.getString("http11protocol.socketfactory.initerror"),
ex);
throw ex;
}

if (socketFactory!=null) {
Iterator<String> attE = attributes.keySet().iterator();
while( attE.hasNext() ) {
String key = attE.next();
Object v=attributes.get(key);
socketFactory.setAttribute(key, v);
}
}

try {
endpoint.init();
} catch (Exception ex) {
log.error(sm.getString("http11protocol.endpoint.initerror"), ex);
throw ex;
}
if (log.isInfoEnabled())
log.info(sm.getString("http11protocol.init", getName()));

}

6.endpoint.init();（endpoint对象是在Http11Protocol的属性中直接new出来的和之前用Digester解析配置不一样）。调用JIoEndpoint.init()：

public void init()
throws Exception {

if (initialized)
return;

// Initialize thread count defaults for acceptor
if (acceptorThreadCount == 0) {
acceptorThreadCount = 1;
}
if (serverSocketFactory == null) {
serverSocketFactory = ServerSocketFactory.getDefault();
}
if (serverSocket == null) {
try {
if (address == null) {
serverSocket = serverSocketFactory.createSocket(port, backlog);
} else {
serverSocket = serverSocketFactory.createSocket(port, backlog, address);
}
} catch (BindException orig) {
String msg;
if (address == null)
msg = orig.getMessage() + " <null>:" + port;
else
msg = orig.getMessage() + " " +
address.toString() + ":" + port;
BindException be = new BindException(msg);
be.initCause(orig);
throw be;
}
}
//if( serverTimeout >= 0 )
//    serverSocket.setSoTimeout( serverTimeout );

initialized = true;

}

7.serverSocketFactory.createSocket()创建ServerSocket占用地址、端口开始监听请求。

初始化过程其实是初始化Connector这边的组件。StandardEngine的并没有初始化。