1.源码下载

下载链接：https://tomcat.apache.org/download-80.cgi#8.5.35

2.源码构建

2.1配置

• 解压缩： 首先idea编译器创建空项目tomcat_original，然后将源代码压缩包解答到该项目当前目录中;
  
• 配置：

1. 进入解压缩文件目录下即D:JetBrainsworksapcetomcat_original，创建文件夹home，并将conf,wappers目录移到该文件夹中；
   
2. 在tomcat源码目录下即D:JetBrainsworksapcetomcat_originalapache-tomcat-8.5.55-src，创建 pom.xml文件，引入tomcat依赖；
3. pom文件中具体内容如下：注意改变artifactId标签的值

<?xml version="1.0" encoding="UTF-8"?> <project xmlns="https://maven.apache.org/POM/4.0.0"          xmlns:xsi="https://www.w3.org/2001/XMLSchema-instance"          xsi:schemaLocation="https://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">       <modelVersion>4.0.0</modelVersion>     <groupId>org.apache.tomcat</groupId>     <artifactId>apache-tomcat-8.5.55-src</artifactId>     <name>Tomcat8.5</name>     <version>8.5</version>       <build>         <finalName>Tomcat8.5</finalName>         <sourceDirectory>java</sourceDirectory>         <!-- <testSourceDirectory>test</testSourceDirectory> -->         <resources>             <resource>                 <directory>java</directory>             </resource>         </resources>         <!-- <testResources>            <testResource>                 <directory>test</directory>            </testResource>         </testResources>-->         <plugins>             <plugin>                 <groupId>org.apache.maven.plugins</groupId>                 <artifactId>maven-compiler-plugin</artifactId>                 <version>2.3</version>                 <configuration>                     <encoding>UTF-8</encoding>                     <source>1.8</source>                     <target>1.8</target>                 </configuration>             </plugin>         </plugins>     </build>       <dependencies>         <dependency>             <groupId>junit</groupId>             <artifactId>junit</artifactId>             <version>4.12</version>             <scope>test</scope>         </dependency>         <dependency>             <groupId>org.easymock</groupId>             <artifactId>easymock</artifactId>             <version>3.4</version>         </dependency>         <dependency>             <groupId>ant</groupId>             <artifactId>ant</artifactId>             <version>1.7.0</version>         </dependency>         <dependency>             <groupId>wsdl4j</groupId>             <artifactId>wsdl4j</artifactId>             <version>1.6.2</version>         </dependency>         <dependency>             <groupId>javax.xml</groupId>             <artifactId>jaxrpc</artifactId>             <version>1.1</version>         </dependency>         <dependency>             <groupId>org.eclipse.jdt.core.compiler</groupId>             <artifactId>ecj</artifactId>             <version>4.5.1</version>         </dependency>             </dependencies> </project> 

2.2源码导入

2.3启动源码

• 主启动类即main方法，路径：tomcat_originalapache-tomcat-8.5.55-srcjavaorgapachecatalinastartupBootstrap.java
  
• 配置启动类：
  
• Vm options参数配置

-Dcatalina.home=D:/JetBrains/worksapce/tomcat_original/apache-tomcat-8.5.55-src/home -Dcatalina.base=D:/JetBrains/worksapce/tomcat_original/apache-tomcat-8.5.55-src/home -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager -Djava.util.logging.config.file=D:/JetBrains/worksapce/tomcat_original/apache-tomcat-8.5.55-src/home/conf/logging.properties 

• 启动过程中如果控制台日志存在乱码现象，则VM options中加入以下配置：

-Duser.language=en -Duser.region=US -Dfile.encoding=UTF-8 

• 配置org.apache.jasper.servlet.JasperInitializer：
  在tomcat的源码org.apache.catalina.startup.ContextConfig中的configureStart函数中手动将JSP解析器初始化：
  context.addServletContainerInitializer(new JasperInitializer(), null);

 protected synchronized void configureStart() {         // Called from StandardContext.start()          if (log.isDebugEnabled()) {             log.debug(sm.getString("contextConfig.start"));         }          if (log.isDebugEnabled()) {             log.debug(sm.getString("contextConfig.xmlSettings",                     context.getName(),                     Boolean.valueOf(context.getXmlValidation()),                     Boolean.valueOf(context.getXmlNamespaceAware())));         }          webConfig();                  //初始化，引入下面一行代码         context.addServletContainerInitializer(new JasperInitializer(), null);          if (!context.getIgnoreAnnotations()) {             applicationAnnotationsConfig();         }         if (ok) {             validateSecurityRoles();         }         。。。。         } 

运行

将源码构建运行后，在浏览器输入https://localhost:8080，则成功进入tomcat的欢迎页面。