
前提环境,安装和配置好java1.8+环境,maven,IDEA
1.下载Tomcat源代码:https://tomcat.apache.org/download-80.cgi#8.5.35
2.创建pom.xml
需要通过Maven组织文件,因此需要在apache-tomcat-8.5.35-src根目录下创建目录中新建catalina-home目录和pom.xml文件,如下,
<?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>Tomcat8.5</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>
apache-tomcat-8.0.53-src目录中的conf和webapps文件夹复制到catalina-home目录中
三、配置IDEA运行项目
Main class设置为org.apache.catalina.startup.Bootstrap
添加VM options
-Dcatalina.home=catalina-home
-Dcatalina.base=catalina-home
-Djava.endorsed.dirs=catalina-home/endorsed
-Djava.io.tmpdir=catalina-home/temp
-Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager
-Djava.util.logging.config.file=catalina-home/conf/logging.properties
说明:如果编译build的时候出现Test测试代码报错,注释该代码即可。本文中的Tomcat源码util.TestCookieFilter类会报错,将其注释即可
运行项目,访问http://localhost:8080,得到结果:
原因是我们直接启动org.apache.catalina.startup.Bootstrap的时候没有加载org.apache.jasper.servlet.JasperInitializer,从而无法编译JSP。解决办法是在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:
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(); context.addServletContainerInitializer(new JasperInitializer(), null); if (!context.getIgnoreAnnotations()) {
applicationAnnotationsConfig();
}
if (ok) {
validateSecurityRoles();
} // Configure an authenticator if we need one
if (ok) {
authenticatorConfig();
} // Dump the contents of this pipeline if requested
if (log.isDebugEnabled()) {
log.debug("Pipeline Configuration:");
Pipeline pipeline = context.getPipeline();
Valve valves[] = null;
if (pipeline != null) {
valves = pipeline.getValves();
}
if (valves != null) {
for (int i = 0; i < valves.length; i++) {
log.debug(" " + valves[i].getClass().getName());
}
}
log.debug("======================");
} // Make our application available if no problems were encountered
if (ok) {
context.setConfigured(true);
} else {
log.error(sm.getString("contextConfig.unavailable"));
context.setConfigured(false);
} }
修改完后,项目再启动,我们再在浏览器访问http://localhost:8080/ ,就可以看到我们所熟悉的经典欢迎页面了