Tomcat 源码下载 以及 启动 运行
首先我们下载Tomcat源码
源码下载地址: https://tomcat.apache.org/download-80.cgi
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解压以及创建必要目录和配置
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建立POM文件
需要通过Maven组织文件,因此需要在根目录下创建目录中新建pom.xml文件:
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pom.xml 文件详情:
<?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>
<!-- https://mvnrepository.com/artifact/javax.xml/jaxrpc -->
<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>
配置IDEA运行项目
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配置maven自动导包
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项目构建好后,请先clean然后install 保证项目没有问题。
缺少jar可以在maven的阿里仓库下载
启动
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Tomcat启动的目录为一个main方法类:org.apache.catalina.startup.Bootstrap
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如果启动或者编译过程中出现Test测试代码报错,注释该代码即可。Tomcat源码util.TestCookieFilter类会报错,将其注释即可
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如果出现下面错误:
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在直接启动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:
添加代码:context.addServletContainerInitializer(new JasperInitializer(), null);
添加位置如下图:
代码在720多行
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修改完后,项目再启动,端口冲突可以在conf文件中的server.xml中修改
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启动项目,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
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如果出现java lang ClassNotFoundException listeners ContextListener的错误
我们可以删除webapps中的文件
然后在webapps中加入war包,也就是我们部署的项目
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启动项目后,会加载我们的项目
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启动完成后,我们访问页面:
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maven依赖可下载:
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