Tomcat架构图
tomcat架构图.png
源码流程如下
###找到启动类
org.apache.catalina.startup.Bootstrap.main()
->org.apache.catalina.startup.Bootstrap.init()
->org.apache.catalina.startup.Catalina.load()
->org.apache.catalina.startup.Catalina.createStartDigester() 解析xml文件
->org.apache.catalina.startup.Catalina.getServer()
->org.apache.catalina.util.LifecycleBase.init()
->org.apache.catalina.core.StandardServer.initInternal() 备注,这里的是StandardServer
// Initialize our defined Services
for (int i = 0; i < services.length; i++) {
services[i].init();
}
->org.apache.catalina.util.LifecycleBase.init()
->org.apache.catalina.core.StandardService.initInternal() 备注,这里的是StandardService
->engine.init();
->executor.init(); 在for循环里面初始化,即executor有多个
->mapperListener.init();
->connector.init(); 在for循环里面初始化 即connector有多个
->org.apache.catalina.connector.Connector.initInternal()
->protocolHandler.init();
->org.apache.coyote.AbstractProtocol.init()
->org.apache.tomcat.util.net.AbstractEndpoint.init()
->org.apache.tomcat.util.net.AbstractEndpoint.bindWithCleanup()
->org.apache.tomcat.util.net.NioEndpoint.bind()
->org.apache.tomcat.util.net.NioEndpoint.initServerSocket()
->serverSock.socket().bind(addr,getAcceptCount()); 调用socket.bind()
整个启动流程图如下:
Tomcat启动流程图.png
结构图如下
Tomcat结构图.png
小结
我们常用的如下
public class LoginServlet extends MyServlet {
@Override
void service(MyTomcat.Request request, MyTomcat.Response response) {
}
}
那么Tomcat容器到底是什么?
伪代码如下
public class MyTomcat {
//1.网络连接
ServerSocket serverSocket = new ServerSocket(8080);
Socket accept = serverSocket.accept();
List<MyServlet> list = new ArrayList<>();
//2.根据连接获取输入输出
InputStream in = accept.getInputStream();
Request request = new Request(in);
OutputStream out = accept.getOutputStream();
Response response = new Response(out);
//解析xml文件 添加servlet
//LoginServlet loginServlet = new LoginServlet();
list.add(loginServlet);
}
将请求和响应封装,提供统一的抽象方法
public abstract class MyServlet {
abstract void service(MyTomcat.Request request, MyTomcat.Response response);
}
网友评论