Tomcat 8.5源码 IDEA打开方式

环境

macos操作系统
idea 2020版本
apache-tomcat-8.5版本

步骤

下载tomcat 8.5

image.png

1.解压。
2.手动添加文件夹catalina-home,将conf、webapps两个文件夹复制进来,并且新建lib、logs、temp、work四个空文件夹。
3.添加pom.xml文件。

<?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</version>

    <build>
        <finalName>Tomcat8.0</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>
        <dependency>
            <groupId>javax.xml.soap</groupId>
            <artifactId>javax.xml.soap-api</artifactId>
            <version>1.4.0</version>
        </dependency>

    </dependencies>
</project>

和下面两张图结构一致即可。

image.png

用IDEA打开
在pom.xml鼠标右击选择as maven project，module构建完毕以后，java目录会变色的。

image.png

通过org.apache.catalina.startup.Bootstrap中的main方法启动。
我们在IDEA中配置Application方式启动，附带启动参数。

image.png

启动参数如下:

-Dcatalina.home/Users/niezhengyu/Downloads/apache-tomcat-8.5.55-src/catalina-home
-Dcatalina.base=/Users/niezhengyu/Downloads/apache-tomcat-8.5.55-src/catalina-home
-Djava.endorsed.dirs=/Users/niezhengyu/Downloads/apache-tomcat-8.5.55-src/catalina-home/endorsed
-Djava.io.tmpdir=/Users/niezhengyu/Downloads/apache-tomcat-8.5.55-src/catalina-home/temp
-Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager
-Djava.util.logging.config.file=/Users/niezhengyu/Downloads/apache-tomcat-8.5.55-src/catalina-home/conf/logging.properties`

路径前缀自行修改即可。
然后我们加一行代码到源码中,手动初始化jsp解析器。
在configureStart类configureStart方法中。
在webConfig()后添加

   context.addServletContainerInitializer(new JasperInitializer(), null);

参考下图注释jsp的地方。

 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();
        // jsp 
        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 (Valve valve : valves) {
                    log.debug("  " + valve.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);
        }

    }

然后启动项目，输入localhost:8080即可。

image.png