如何debug tomcat源码

1. 下载tomcat 以及对应源码包

   
   

解压

2. 使用idea打开tomcat源码，添加pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>org.apache.tomcat</groupId>
    <artifactId>tomcat8</artifactId>
    <name>tomcat8</name>
    <version>8.0</version>
    <build>
        <finalName>tomcat8</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>3.5.1</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>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>4.6.1</version>
        </dependency>
        <dependency>
            <groupId>org.easymock</groupId>
            <artifactId>easymock</artifactId>
            <version>3.4</version>
            <scope>test</scope>
        </dependency>

    </dependencies>
</project>

一些常规操作，配置jvm，导入maven...

3.运行
找到Bootstrap类的main方法点击运行，你会发现失败了，如下

修改下启动配置

把红框处从源码路径改为发行版本路径。

再次点击运行就ok了。

4. 验证
   打开 localhost:8080 如果出现以下界面，代表启动成功，然后你就可以debug了。