I use online programs also have their own experiment n times can not accept the request and response, and found that the background is always 404, can guarantee the project code no problem, now problem positioning to tomcat and web. The XML configuration files,
Tomcat startup without warning, error, this is a tomcat localhost log:

Start is successful, the log is as follows:

 "D: \ \ Program Files \ Java \ apache tomcat - 9.0.30 \ bin \ catalina bat" run 
Using CATALINA_BASE: "C: \ Users \ Pluto \. IntelliJIdea2019.3 \ system \ tomcat \ Unnamed_governmentPublic - for SpringMVC - test" 
Using the CATALINA_HOME: "D: \ \ Program Files \ Java \ apache tomcat - 9.0.30" 
Using CATALINA_TMPDIR: "D: \ \ Program Files \ Java \ apache tomcat - 9.0.30 \ " 
Using JRE_HOME: "D: \ \ Program Files \ Java \ graalvm - ce - 19.2.1" 
Using the CLASSPATH: "D: \ \ Program Files \ Java \ apache tomcat - 9.0.30 \ bin \ the bootstrap jar; D: \ \ Program Files \ Java \ apache tomcat - 9.0.30 \ bin \ tomcat - juli. Jar 
"[the 12:35:58 2020-04-08, 093] an Artifact governmentPublic - for SpringMVC - test: war exploded: Waiting for the server connection to start an Artifact deployment... 
12:35:59 - Apr 08-2020. 682 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. The log Server. The Server version: apache Tomcat/9.0.30 
12:35:59 - Apr 08-2020. 688 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. The log server build: Dec 7 2019 16:42:04 UTC 
12:35:59 - Apr 08-2020. 688 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. The log server version number (: 9.0.30.0 
12:35:59 - Apr 08-2020. 688 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. Log OS Name: Windows 10 
12:35:59 - Apr 08-2020. 688 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. Log OS. Version: 10.0 
12:35:59 - Apr 08-2020. 688 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. Log architecture: amd64 
12:35:59 - Apr 08-2020. 688 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. Log Java environment variables: D: \ \ Program Files \ Java \ graalvm - ce - 19.2.1 \ jre 
12:35:59 - Apr 08-2020. 689 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. Log the JVM version: 1.8.0 comes with _232-20191009144847. Buildslave. Jdk8u SRC - tar - b07 
12:35:59 - Apr 08-2020. 689 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. Log JVM. Suppliers: Oracle Corporation 
12:35:59 - Apr 08-2020. 689 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. Log CATALINA_BASE: C: \ Users \ Pluto \. IntelliJIdea2019.3 \ system \ tomcat \ Unnamed_governmentPublic - for SpringMVC - test 
12:35:59 - Apr 08-2020. 689 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. Log the CATALINA_HOME: D: \ \ Program Files \ Java \ apache tomcat -- 9.0.30 
12:35:59 - Apr 08-2020. 690 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. Log Command line argument: - Djava. Util. Logging.. Config file=C: \ Users \ Pluto \. IntelliJIdea2019.3 \ system \ tomcat \ Unnamed_governmentPublic - for SpringMVC - test \ conf \ logging properties 
12:35:59 - Apr 08-2020. 690 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. Log Command line argument: - Djava. Util. Logging. The manager=org. Apache. Juli. ClassLoaderLogManager 
12:35:59 - Apr 08-2020. 690 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. Log Command line argument: - Dfile. Encoding=utf-8 
12:35:59 - Apr 08-2020. 690 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. Log Command line argument: - Dcom. Sun. Management jmxremote=
12:35:59 - Apr 08-2020. 691 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. Log Command line argument: - Dcom. Sun. Management jmxremote. Port=1099 
12:35:59 - Apr 08-2020. 691 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. Log Command line argument: - Dcom. Sun. Management jmxremote. SSL=false 
12:35:59 - Apr 08-2020. 691 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. Log Command line argument: - Dcom. Sun. Management jmxremote. Password. The file=C: \ Users \ Pluto \. IntelliJIdea2019.3 \ system \ tomcat \ Unnamed_governmentPublic - for SpringMVC - test \ jmxremote password 
12:35:59 - Apr 08-2020. 691 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. Log Command line argument: - Dcom. Sun. Management jmxremote. Access the file=C: \ Users \ Pluto \. IntelliJIdea2019.3 \ system \ tomcat \ Unnamed_governmentPublic - for SpringMVC - test \ jmxremote access 
12:35:59 - Apr 08-2020. 691 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. Log Command line argument: - Djava. Rmi. Server hostname=127.0.0.1 
12:35:59 - Apr 08-2020. 691 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. Log Command line argument: - Djdk. TLS. EphemeralDHKeySize=2048 
12:35:59 - Apr 08-2020. 691 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. Log Command line argument: - Djava. Protocol. The handler. PKGS=org. Apache. Catalina. Webresources 
12:35:59 - Apr 08-2020. 692 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. Log Command line argument: - Dignore. Endorsed inside. Dirs=
12:35:59 - Apr 08-2020. 692 information [main] org. Apache. Catalina. Startup. VersionLoggerListener. Log Command line argument: - Dcatalina. Base=C: \ Users \ Pluto \. IntelliJIdea2019.3 \ system \ tomcat \ Unnamed_governmentPublic - for SpringMVC - test 
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