server.xml

• 首先要看下server.xml中Service的配置，这样你便知道了需要了解的4个部分

xml

<!--
    每个Service元素只能有一个Engine元素.元素处理在同一个<Service>中所有<Connector>元素接收到的客户请求
-->

<Service name="Catalina">
<!-- 1. 属性说明
	name:Service的名称
-->

    <!--2. 一个或多个excecutors -->
    <!--
    <Executor name="tomcatThreadPool" namePrefix="catalina-exec-"
        maxThreads="150" minSpareThreads="4"/>
    -->

    <!--
		3.Connector元素:
			由Connector接口定义.<Connector>元素代表与客户程序实际交互的组件,它负责接收客户请求,以及向客户返回响应结果.
    -->
    <Connector port="80" maxHttpHeaderSize="8192"
               maxThreads="150" minSpareThreads="25" maxSpareThreads="75"
               enableLookups="false" redirectPort="8443" acceptCount="100"
               connectionTimeout="20000" disableUploadTimeout="true" />
    <!-- 属性说明
		port:服务器连接器的端口号,该连接器将在指定端口侦听来自客户端的请求。
		enableLookups:如果为true，则可以通过调用request.getRemoteHost()进行DNS查询来得到远程客户端的实际主机名；
					若为false则不进行DNS查询，而是返回其ip地址。
		redirectPort:服务器正在处理http请求时收到了一个SSL传输请求后重定向的端口号。
		acceptCount:当所有可以使用的处理请求的线程都被用光时,可以放到处理队列中的请求数,超过这个数的请求将不予处理，而返回Connection refused错误。
		connectionTimeout:等待超时的时间数（以毫秒为单位）。
		maxThreads:设定在监听端口的线程的最大数目,这个值也决定了服务器可以同时响应客户请求的最大数目.默认值为200。
		protocol:必须设定为AJP/1.3协议。
		address:如果服务器有两个以上IP地址,该属性可以设定端口监听的IP地址,默认情况下,端口会监听服务器上所有IP地址。
		minProcessors:服务器启动时创建的处理请求的线程数，每个请求由一个线程负责。
		maxProcessors:最多可以创建的处理请求的线程数。
		minSpareThreads:最小备用线程 。
		maxSpareThreads:最大备用线程。
		debug:日志等级。
		disableUploadTimeout:禁用上传超时,主要用于大数据上传时。
    -->


    <Connector port="8009" enableLookups="false" redirectPort="8443" protocol="AJP/1.3" />
    <!-- 负责和其他HTTP服务器建立连接。在把Tomcat与其他HTTP服务器集成时就需要用到这个连接器。 -->
	
    <!--
		4. Engine
    -->
    <Engine name="Catalina" defaultHost="localhost">
    
    </Engine>
  </Service>

Service中的接口设计

• 公共属性, name等

java

/**
  * @return the name of this Service.
  */
public String getName();

/**
  * Set the name of this Service.
  *
  * @param name The new service name
  */
public void setName(String name);

• 父Server相关

java

/**
  * @return the <code>Server</code> with which we are associated (if any).
  */
public Server getServer();

/**
  * Set the <code>Server</code> with which we are associated (if any).
  *
  * @param server The server that owns this Service
  */
public void setServer(Server server);

/**
  * @return the parent class loader for this component. If not set, return
  * {@link #getServer()} {@link Server#getParentClassLoader()}. If no server
  * has been set, return the system class loader.
  */
public ClassLoader getParentClassLoader();

/**
  * Set the parent class loader for this service.
  *
  * @param parent The new parent class loader
  */
public void setParentClassLoader(ClassLoader parent);

/**
  * @return the domain under which this container will be / has been
  * registered.
  */
public String getDomain();

• Connector相关

java

/**
  * Add a new Connector to the set of defined Connectors, and associate it
  * with this Service's Container.
  *
  * @param connector The Connector to be added
  */
public void addConnector(Connector connector);

/**
  * Find and return the set of Connectors associated with this Service.
  *
  * @return the set of associated Connectors
  */
public Connector[] findConnectors();

/**
  * Remove the specified Connector from the set associated from this
  * Service.  The removed Connector will also be disassociated from our
  * Container.
  *
  * @param connector The Connector to be removed
  */
public void removeConnector(Connector connector);

• Engine

java

/**
  * @return the <code>Engine</code> that handles requests for all
  * <code>Connectors</code> associated with this Service.
  */
public Engine getContainer();

/**
  * Set the <code>Engine</code> that handles requests for all
  * <code>Connectors</code> associated with this Service.
  *
  * @param engine The new Engine
  */
public void setContainer(Engine engine);

• Excutor相关

java

/**
  * Adds a named executor to the service
  * @param ex Executor
  */
public void addExecutor(Executor ex);

/**
  * Retrieves all executors
  * @return Executor[]
  */
public Executor[] findExecutors();

/**
  * Retrieves executor by name, null if not found
  * @param name String
  * @return Executor
  */
public Executor getExecutor(String name);

/**
  * Removes an executor from the service
  * @param ex Executor
  */
public void removeExecutor(Executor ex);

StandardService的实现

属性和父Server相关比较简单，这里主要看下其它的方法：

Engine相关

java

private Engine engine = null;

@Override
public Engine getContainer() {
    return engine;
}

@Override
public void setContainer(Engine engine) {
    Engine oldEngine = this.engine;
    if (oldEngine != null) {
        oldEngine.setService(null);
    }
    this.engine = engine;
    if (this.engine != null) {
        this.engine.setService(this);
    }
    if (getState().isAvailable()) {
        if (this.engine != null) {