启动信息：

D:\javatool\javaee\apache-tomcat-8.5.37\bin\catalina.bat run

[2019-03-20 11:54:41,246] Artifact JDBCMessageBoard:war exploded: Waiting for server connection to start artifact deployment...

Using CATALINA_BASE:   "C:\Users\asus\.IntelliJIdea2018.3\system\tomcat\_JDBCMessageBoard"

Using CATALINA_HOME:   "D:\javatool\javaee\apache-tomcat-8.5.37"

Using CATALINA_TMPDIR: "D:\javatool\javaee\apache-tomcat-8.5.37\temp"

Using JRE_HOME:        "C:\Program Files\Java\jdk1.8.0_191"

Using CLASSPATH:       "D:\javatool\javaee\apache-tomcat-8.5.37\bin\bootstrap.jar;D:\javatool\javaee\apache-tomcat-8.5.37\bin\tomcat-juli.jar"

Connected to the target VM, address: '127.0.0.1:1625', transport: 'socket'

20-Mar-2019 11:54:54.755 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Server version:        Apache Tomcat/8.5.37

20-Mar-2019 11:54:54.773 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Server built:          Dec 12 2018 12:07:02 UTC

20-Mar-2019 11:54:54.774 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Server number:         8.5.37.0

20-Mar-2019 11:54:54.774 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log OS Name:               Windows 10

20-Mar-2019 11:54:54.774 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log OS Version:            10.0

20-Mar-2019 11:54:54.774 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Architecture:          amd64

20-Mar-2019 11:54:54.774 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Java Home:             C:\Program Files\Java\jdk1.8.0_191\jre

20-Mar-2019 11:54:54.775 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log JVM Version:           1.8.0_191-b12

20-Mar-2019 11:54:54.775 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log JVM Vendor:            Oracle Corporation

20-Mar-2019 11:54:54.775 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log CATALINA_BASE:         C:\Users\asus\.IntelliJIdea2018.3\system\tomcat\_JDBCMessageBoard

20-Mar-2019 11:54:54.775 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log CATALINA_HOME:         D:\javatool\javaee\apache-tomcat-8.5.37

20-Mar-2019 11:54:54.776 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.util.logging.config.file=C:\Users\asus\.IntelliJIdea2018.3\system\tomcat\_JDBCMessageBoard\conf\logging.properties

20-Mar-2019 11:54:54.776 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager

20-Mar-2019 11:54:54.776 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -agentlib:jdwp=transport=dt_socket,address=127.0.0.1:1625,suspend=y,server=n

20-Mar-2019 11:54:54.776 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -javaagent:C:\Users\asus\.IntelliJIdea2018.3\system\captureAgent\debugger-agent.jar

20-Mar-2019 11:54:54.776 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcom.sun.management.jmxremote=

20-Mar-2019 11:54:54.776 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcom.sun.management.jmxremote.port=1099

20-Mar-2019 11:54:54.776 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcom.sun.management.jmxremote.ssl=false

20-Mar-2019 11:54:54.776 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcom.sun.management.jmxremote.authenticate=false

20-Mar-2019 11:54:54.776 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.rmi.server.hostname=127.0.0.1

20-Mar-2019 11:54:54.777 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djdk.tls.ephemeralDHKeySize=2048

20-Mar-2019 11:54:54.777 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.protocol.handler.pkgs=org.apache.catalina.webresources

20-Mar-2019 11:54:54.777 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dignore.endorsed.dirs=

20-Mar-2019 11:54:54.777 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcatalina.base=C:\Users\asus\.IntelliJIdea2018.3\system\tomcat\_JDBCMessageBoard

20-Mar-2019 11:54:54.777 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcatalina.home=D:\javatool\javaee\apache-tomcat-8.5.37

20-Mar-2019 11:54:54.777 淇℃伅 [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.io.tmpdir=D:\javatool\javaee\apache-tomcat-8.5.37\temp

20-Mar-2019 11:54:54.778 淇℃伅 [main] org.apache.catalina.core.AprLifecycleListener.lifecycleEvent Loaded APR based Apache Tomcat Native library [1.2.19] using APR version [1.6.5].

20-Mar-2019 11:54:54.778 淇℃伅 [main] org.apache.catalina.core.AprLifecycleListener.lifecycleEvent APR capabilities: IPv6 [true], sendfile [true], accept filters [false], random [true].

20-Mar-2019 11:54:54.778 淇℃伅 [main] org.apache.catalina.core.AprLifecycleListener.lifecycleEvent APR/OpenSSL configuration: useAprConnector [false], useOpenSSL [true]

20-Mar-2019 11:54:54.787 淇℃伅 [main] org.apache.catalina.core.AprLifecycleListener.initializeSSL OpenSSL successfully initialized [OpenSSL 1.1.1a  20 Nov 2018]

20-Mar-2019 11:54:56.942 淇℃伅 [main] org.apache.coyote.AbstractProtocol.init Initializing ProtocolHandler ["http-nio-8080"]

20-Mar-2019 11:54:57.014 淇℃伅 [main] org.apache.tomcat.util.net.NioSelectorPool.getSharedSelector Using a shared selector for servlet write/read

20-Mar-2019 11:54:57.061 淇℃伅 [main] org.apache.coyote.AbstractProtocol.init Initializing ProtocolHandler ["ajp-nio-8009"]

20-Mar-2019 11:54:57.066 淇℃伅 [main] org.apache.tomcat.util.net.NioSelectorPool.getSharedSelector Using a shared selector for servlet write/read

20-Mar-2019 11:54:57.068 淇℃伅 [main] org.apache.catalina.startup.Catalina.load Initialization processed in 4815 ms

20-Mar-2019 11:54:57.227 淇℃伅 [main] org.apache.catalina.core.StandardService.startInternal Starting service [Catalina]

20-Mar-2019 11:54:57.227 淇℃伅 [main] org.apache.catalina.core.StandardEngine.startInternal Starting Servlet Engine: Apache Tomcat/8.5.37

20-Mar-2019 11:54:57.351 淇℃伅 [main] org.apache.coyote.AbstractProtocol.start Starting ProtocolHandler ["http-nio-8080"]

20-Mar-2019 11:54:57.384 淇℃伅 [main] org.apache.coyote.AbstractProtocol.start Starting ProtocolHandler ["ajp-nio-8009"]

20-Mar-2019 11:54:57.410 淇℃伅 [main] org.apache.catalina.startup.Catalina.start Server startup in 342 ms

Connected to server

[2019-03-20 11:54:57,849] Artifact JDBCMessageBoard:war exploded: Artifact is being deployed, please wait...

20-Mar-2019 11:55:00.081 璀﹀憡 [RMI TCP Connection(5)-127.0.0.1] org.apache.tomcat.util.descriptor.web.WebXml.setVersion Unknown version string [4.0]. Default version will be used.

20-Mar-2019 11:55:02.729 淇℃伅 [RMI TCP Connection(5)-127.0.0.1] org.apache.jasper.servlet.TldScanner.scanJars At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.

[2019-03-20 11:55:03,154] Artifact JDBCMessageBoard:war exploded: Artifact is deployed successfully

[2019-03-20 11:55:03,155] Artifact JDBCMessageBoard:war exploded: Deploy took 5,306 milliseconds

20-Mar-2019 11:55:07.595 淇℃伅 [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory [D:\javatool\javaee\apache-tomcat-8.5.37\webapps\manager]

20-Mar-2019 11:55:08.346 淇℃伅 [localhost-startStop-1] org.apache.jasper.servlet.TldScanner.scanJars At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.

20-Mar-2019 11:55:08.363 淇℃伅 [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory [D:\javatool\javaee\apache-tomcat-8.5.37\webapps\manager] has finished in [766] ms

index.jsp

MessageBoard

MessageListServlet:

请求重定向：request.getRequestDispatcher("/WEB-INF/views/biz/message_list.jsp").forward(request, response);

web.xml:

MessageListServlet

com.imooc.jdbc.servlet.MessageListServlet

MessageListServlet

/message/list.do

/index.jsp

老师，看一下问题出在哪儿？为什么页面也没有跳转？