二、Tomcat目录

tomcat
|---bin Tomcat：存放启动和关闭tomcat脚本；

|---conf Tomcat：存放不同的配置文件（server.xml和web.xml）；
|---doc：存放Tomcat文档；
|---lib/japser/common：存放Tomcat运行需要的库文件（JARS）；
|---logs：存放Tomcat执行时的LOG文件；
|---src：存放Tomcat的源代码；
|---webapps：Tomcat的主要Web发布目录（包括应用程序示例）；
|---work：存放jsp编译后产生的class文件；

三、Tomcat类加载

    Bootstrap($JAVA_HOME/jre/lib/ext/*.jar)
System($CLASSPATH/*.class和指定的jar)
Common($CATALINA_HOME/common 下的classes,lib,endores三个子目录)
Catalina ($CATALINA_HOME/server/下的classes和lib目录仅对Tomcat可见)
&Shared($CATALINA_HOME/shared/下的classes和lib目录以及$CATALINA_HOME/lib目录)仅对Web应用程序可见,对Tomcat不可见WebApp($WEBAPP/Web-INF/*仅对该WEB应用可见classes/*.class lib/*.jar)

加载类和资源的顺序为：
1、/Web-INF/classes

2、/Web-INF/lib/*.jar

3、Bootstrap

4、System

5、$CATALINA_HOME/common/classes
6、$CATALINA_HOME/common/endores/*.jar

7、$CATALINA_HOME/common/lib/*.jar

8、$CATALINA_HOME/shared/classes
9、$CATALINA_HOME/shared/lib/*.jar

四、server.xml配置简介：

下面讲述这个文件中的基本配置信息，更具体的配置信息请参考tomcat的文档：
    server:
          1、port 指定一个端口，这个端口负责监听关闭tomcat的请求
          2、shutdown 指定向端口发送的命令字符串
    service:
          1、name 指定service的名字
    Connector (表示客户端和service之间的连接)：
          1、port 指定服务器端要创建的端口号，并在这个断口监听来自客户端的请求
          2、minProcessors 服务器启动时创建的处理请求的线程数
          3、maxProcessors 最大可以创建的处理请求的线程数
          4、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
          5、redirectPort 指定服务器正在处理http请求时收到了一个SSL传输请求后重定向的

端口号
          6、acceptCount 指定当所有可以使用的处理请求的线程数都被使用时，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
          7、connectionTimeout 指定超时的时间数(以毫秒为单位)
    Engine (表示指定service中的请求处理机，接收和处理来自Connector的请求)：
          1、defaultHost 指定缺省的处理请求的主机名，它至少与其中的一个host元素的name

属性值是一样的 

在Eclipse方面使用Ｔｏｍｃａｔ的插件

Plugin features

• Starting and stopping Tomcat 4.x, 5.x and 6.x

• Registering Tomcat process to Eclipse debugger

• Creating a WAR project (wizard can update server.xml file)

• Adding Java Projects to Tomcat classpath

• Setting Tomcat JVM parameters, classpath and bootclasspath

• Exporting a Tomcat project to a WAR File

• Capability to use a custom Tomcat classloader to load classes in several java projects at the same classloader level than classes in a Tomcat project, see readmeDevLoader.html (Thanks Martin Kahr)

Support and contributions

Contact plugintomcat@sysdeo.fr

Download

This plugin is free and open-source

Tomcat 4.x patch for JSP debugging (Thanks to Johan Compagner)

To install this patch, unzip the file in <%TOMCAT_HOME%>/classes for tomcat 4.0x, or in <%TOMCAT_HOME%>/common/classes for Tomcat 4.1.x

Installation

• This plugin does not contain Tomcat.
  (Download and install Tomcat before using this plugin).
  This is a design choice not to include Tomcat in the plugin distribution, this way the same plugin version can works with any Tomcat version.
  

• Download tomcatPluginVxxx.zip

• Unzip it in your_Eclipse_Home/plugins

• Plugin activation for Eclipse 3.x :
  - launch eclipse once using this option : -clean
  - if Tomcat icons are not shown in toolbar : select menu 'Window>Customize Perspective...>Commands', and check 'Tomcat' in 'Available command groups'
  

• Set Tomcat version and Tomcat home : Workbench -> Preferences, select Tomcat and set Tomcat version and Tomcat home (Tomcat version and Tomcat home are the only required fields, other settings are there for advanced configuration).

• This plugin launches Tomcat using the default JRE checked in Eclipe preferences window.
  To set a JDK as default JRE for Eclipse open the preference window : Window -> Preferences -> Java -> Installed JREs.
  This JRE must be a JDK (This is a Tomcat prerequisite).
  

• The plugin sets itself Tomcat classpath and bootclasspath. Use Preferences -> Tomcat ->JVM Settings, only if you need specific settings.

Documentation and tutorials

Official documation (french) : http://www.eclipsetotale.com/articles/tomcat/tomcatPluginDocFR.html

Tutorials (english) :

• The Power of Three - Eclipse, Tomcat, and Struts

• Tomcat Tutorial: HelloWorld for Complete Fools

Troubleshooting

• In some case, despite it is correctly unzipped in Eclipse 3 'plugins' directory, the plugin is not loaded : run Eclipse with the -clean option to solve the problem.

• ClassNotFound when using DevLoader and launching Tomcat 5.5.12 and above
  Workaround : set context definition mode (Preferences->Tomcat) to 'Context files'.
  Explanations :
  This problem is due to a change in Tomcat 5.5.12 and above (see http://issues.apache.org/bugzilla/show_bug.cgi?id=37302 ,
  We hope this bug will be fix but it seems that Tomcat developers don't care about it because it happens when a context containing its own loader is defined in server.xml file and since Tomcat 5 defining context in server.xml is not recommended)
  

• ClassNotFoundException on javac/Main when accessing JSP : Tomcat is started with a JRE instead of a JDK.

• If you have a problem with the plugin check eclipse log file (<%Your_Workspace_dir%>/.metadata/.log)

If you have any problem with this plugin send an email to plugintomcat@sysdeo.fr .
(Select this button : Preferences->Tomcat->JVM Settings->Dump configuration to .log file, and include in your email the corresponding lines of your .log file, it is in <%Your_Workspace_dir%>/.metadata)

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd" version="2.4">
  <display-name>myweb</display-name><!--站点名称-->
  <description>这里是站点描述</description>
  <icon>
    <small-icon>/images/small.gif</small-icon><!--小图标的路径16*16,必须为gif jpge格式-->
    <large-icon>/images/large.gif</large-icon><!--大图标的路径32*32,必须为gif jpge格式-->
  </icon>
  <!--如果存在<distributable/>则代表该站点能在多个JSP Container之间分散执行(分布式)-->
  <distributable/>




  <context-param><!--环境参数,设置常量,取得常量  this.getInitParameter("context");-->
    <param-name>context</param-name>
    <param-value>10000</param-value>
  </context-param>
  <filter><!--声明filter-->

    <filter-name>filterName</filter-name>
    <filter-class>filter.filterName</filter-class>
    <init-param>
      <param-name>encoding</param-name>
      <param-value>UTF-8</param-value>
    </init-param>
  </filter>
  <filter-mapping><!--定义filter所对应的URL-->
    <filter-name>filterName</filter-name>
    <url-pattern>/filterName</url-pattern>
    <dispatcher>REQUEST|INCLUDE|FORWARD|ERROR</dispatcher><!--filter对应的请求方式,有4种方式,默认REQUEST-->
  </filter-mapping>
  <listener><!--设定Listener接口-->
    <listener-class>listener.ListenerClassName</listener-class>
  </listener>
  <servlet><!--声明servlet的数据-->
    <servlet-name>servletName</servlet-name>
    <servlet-class>servlet.servletName</servlet-class>
    <init-param><!--初始化参数,可以在init()中使用ServletConfig().getInitParamenter("name")取得-->
      <param-name>name</param-name>
      <param-value>123</param-value>
    </init-param>
    <load-on-startup>n</load-on-startup><!--站点启动时,此servlet会被自动加载执行,1表示最早,2,3...-->

  </servlet>
  <servlet-mapping><!--定义servlet所对应的URL-->

    <servlet-name>name</servlet-name>
    <url-pattern>/name</url-pattern>
  </servlet-mapping>
  <session-config><!--设置session超时时间（20分钟）默认按服务器配置-->
    <session-timeout>20</session-timeout>
  </session-config>
  <mime-mapping><!--定义某个扩展名和某个MIME Type做映射-->
    <extension>doc</extension>
    <mime-type>application/vnd.ms-word</mime-type>
  </mime-mapping>
  <welcome-file-list><!--设置首页列表-->
    <welcome-file>index.jsp</welcome-file>
  </welcome-file-list>
  <error-page><!--将错误代码对应到WEB站点的资源路径-->
    <error-code>错误代码</error-code>Exception
    <location>/路径/</location>

  </error-page>
  <error-page><!--将异常的种类对应到WEB站点的资源路径-->
    <exception-type>Exception</exception-type>
    <location>/路径/</location>

  </error-page>

  <jsp-config><!--JSP的相关配置-->
    <taglib><!--JSP所用到的Tag Library-->
      <taglib-uri>URI</taglib-uri>
      <taglib-location>/WEB-INF/lib/xxx.tld</taglib-location>
    </taglib>
    <jsp-property-group>
      <description>此设定的说明</description>
      <display-name>Name</display-name>
      <url-pattern>URL</url-pattern><!--此设定影响的范围-->
      <el-ignored>true|false</el-ignored><!--true表示不支持EL语法-->
      <scripting-invalid>encoding</scripting-invalid><!--jsp的编码-->
      <include-coda>...jspf</include-coda><!--JSP的结尾,扩展名.jspf-->
    </jsp-property-group>
  </jsp-config>
  <resource-ref><!--利用JNDI取得站点可利用的资源-->
    <description>资源说明</description>
    <res-ref-name>资源名称</res-ref-name>
    <res-type>资源种类</res-type>
    <res-auth>Application|Container</res-auth><!--资源经由什么许可-->
    <res-sharing-scope>Shareable|Unshareable</res-sharing-scope><!--资源是否可以共享,默认为Shareable-->
  </resource-ref>
</web-app>