Q: HTTP Status 404 – Not Found while app is running I have a problem with my spring app. While I run it, I am getting below exception:

 It had worked correctly, but app didn't see changes in .jsp files and loaded the same page every time.
I faced with this problem in the past? but unfortunately I couldn't resolve this, and recreated project. 
My project struct:

My spring-mvc-demo-servlet.xml file:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    xsi:schemaLocation="
        http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/mvc
        http://www.springframework.org/schema/mvc/spring-mvc.xsd">

    <!-- Step 3: Add support for component scanning -->
    <context:component-scan base-package="com.spring" />

    <!-- Step 4: Add support for conversion, formatting and validation support -->
    <mvc:annotation-driven/>

    <!-- Step 5: Define Spring MVC view resolver -->
    <bean
        class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/view/" />
        <property name="suffix" value=".jsp" />
    </bean>

</beans>

My web.xml:
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="http://xmlns.jcp.org/xml/ns/javaee"
    xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
    id="WebApp_ID" version="3.1">

    <display-name>spring-mvc-demo</display-name>

    <!-- Spring MVC Configs -->

    <!-- Step 1: Configure Spring MVC Dispatcher Servlet -->
    <servlet>
        <servlet-name>dispatcher</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>/spring-mvc-demo-servlet.xml</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>

    <!-- Step 2: Set up URL mapping for Spring MVC Dispatcher Servlet -->
    <servlet-mapping>
        <servlet-name>dispatcher</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>

</web-app>

Maybe there is a problem with artifacts or tomcat configuration, because I changed it while tried resolve this error. 
My pom.xml:
    <?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>com.spring</groupId>
    <artifactId>SpringgMVC</artifactId>
    <version>1.0-SNAPSHOT</version>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>
        </plugins>
    </build>

    <dependencies>
        <!-- https://mvnrepository.com/artifact/org.springframework/spring-core -->

        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.11</version>
            <scope>test</scope>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.springframework/spring-core -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>5.1.4.RELEASE</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.springframework/spring-beans -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-beans</artifactId>
            <version>5.1.4.RELEASE</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.springframework/spring-context -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>5.1.4.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>javax.annotation</groupId>
            <artifactId>javax.annotation-api</artifactId>
            <version>LATEST</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.springframework/spring-webmvc -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.1.4.RELEASE</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/javax.servlet/jsp-api -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jsp-api</artifactId>
            <version>2.0</version>
            <scope>provided</scope>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.apache.tomcat/tomcat -->
        <dependency>
            <groupId>org.apache.tomcat</groupId>
            <artifactId>tomcat</artifactId>
            <version>8.5.39</version>
            <type>pom</type>
        </dependency>

    </dependencies>


Update:::
I created a new artfacts, and received a new error:

my artifacts:

Although there are problem in web.xml.

Tomcat Log
    "C:\Program Files\Apache Software Foundation\Tomcat 8.5\bin\catalina.bat" run
[2019-05-16 03:36:54,591] Artifact SpringgMVC:war exploded: Waiting for server connection to start artifact deployment...
Using CATALINA_BASE:   "C:\Users\__it\.IntelliJIdea2018.3\system\tomcat\Unnamed_SpringgMVC"
Using CATALINA_HOME:   "C:\Program Files\Apache Software Foundation\Tomcat 8.5"
Using CATALINA_TMPDIR: "C:\Program Files\Apache Software Foundation\Tomcat 8.5\temp"
Using JRE_HOME:        "C:\Program Files\Java\jdk1.8.0_151"
Using CLASSPATH:       "C:\Program Files\Apache Software Foundation\Tomcat 8.5\bin\bootstrap.jar;C:\Program Files\Apache Software Foundation\Tomcat 8.5\bin\tomcat-juli.jar"
16-May-2019 15:36:55.256 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Server version:        Apache Tomcat/8.5.39
16-May-2019 15:36:55.257 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Server built:          Mar 14 2019 11:24:26 UTC
16-May-2019 15:36:55.257 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Server number:         8.5.39.0
16-May-2019 15:36:55.257 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log OS Name:               Windows 10
16-May-2019 15:36:55.257 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log OS Version:            10.0
16-May-2019 15:36:55.257 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Architecture:          amd64
16-May-2019 15:36:55.257 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Java Home:             C:\Program Files\Java\jdk1.8.0_151\jre
16-May-2019 15:36:55.257 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log JVM Version:           1.8.0_151-b12
16-May-2019 15:36:55.258 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log JVM Vendor:            Oracle Corporation
16-May-2019 15:36:55.258 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log CATALINA_BASE:         C:\Users\__it\.IntelliJIdea2018.3\system\tomcat\Unnamed_SpringgMVC
16-May-2019 15:36:55.258 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log CATALINA_HOME:         C:\Program Files\Apache Software Foundation\Tomcat 8.5
16-May-2019 15:36:55.258 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.util.logging.config.file=C:\Users\__it\.IntelliJIdea2018.3\system\tomcat\Unnamed_SpringgMVC\conf\logging.properties
16-May-2019 15:36:55.258 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager
16-May-2019 15:36:55.258 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcom.sun.management.jmxremote=
16-May-2019 15:36:55.258 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcom.sun.management.jmxremote.port=1099
16-May-2019 15:36:55.258 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcom.sun.management.jmxremote.ssl=false
16-May-2019 15:36:55.258 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcom.sun.management.jmxremote.authenticate=false
16-May-2019 15:36:55.258 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.rmi.server.hostname=127.0.0.1
16-May-2019 15:36:55.258 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djdk.tls.ephemeralDHKeySize=2048
16-May-2019 15:36:55.258 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.protocol.handler.pkgs=org.apache.catalina.webresources
16-May-2019 15:36:55.258 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dignore.endorsed.dirs=
16-May-2019 15:36:55.258 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcatalina.base=C:\Users\__it\.IntelliJIdea2018.3\system\tomcat\Unnamed_SpringgMVC
16-May-2019 15:36:55.258 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Dcatalina.home=C:\Program Files\Apache Software Foundation\Tomcat 8.5
16-May-2019 15:36:55.259 INFO [main] org.apache.catalina.startup.VersionLoggerListener.log Command line argument: -Djava.io.tmpdir=C:\Program Files\Apache Software Foundation\Tomcat 8.5\temp
16-May-2019 15:36:55.259 INFO [main] org.apache.catalina.core.AprLifecycleListener.lifecycleEvent The APR based Apache Tomcat Native library which allows optimal performance in production environments was not found on the java.library.path: [C:\Program Files\Java\jdk1.8.0_151\bin;C:\WINDOWS\Sun\Java\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\Program Files (x86)\Common Files\Oracle\Java\javapath;C:\ProgramData\Oracle\Java\javapath;C:\ProgramData\Boxstarter;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\WINDOWS\System32\WindowsPowerShell\v1.0\;C:\Program Files\Git\cmd;C:\ProgramData\chocolatey\bin;C:\Program Files (x86)\Yarn\bin;C:\Program Files\dotnet\;C:\Program Files\Calibre2\;C:\WINDOWS\System32\OpenSSH\;C:\Program Files (x86)\Microsoft VS Code\bin;C:\Program Files\TortoiseGit\bin;C:\Python27\gnuplot\binary;C:\Program Files\Microsoft SQL Server\Client SDK\ODBC\130\Tools\Binn\;C:\Program Files (x86)\Microsoft SQL Server\140\Tools\Binn\;C:\Program Files\Microsoft SQL Server\140\Tools\Binn\;C:\Program Files\Microsoft SQL Server\140\DTS\Binn\;C:\Program Files (x86)\Microsoft SQL Server\Client SDK\ODBC\130\Tools\Binn\;C:\Program Files (x86)\Microsoft SQL Server\140\DTS\Binn\;C:\Program Files (x86)\Microsoft SQL Server\140\Tools\Binn\ManagementStudio\;C:\Program Files (x86)\Microsoft VS Code\bin;C:\Users\__it\AppData\Local\Microsoft\WindowsApps;C:\Users\__it\AppData\Local\Yarn\.bin;C:\Program Files\MongoDB\Server\3.4\bin;c:\Program Files\PhantomJS 2.1.1\bin;C:\ProgramData\Oracle\Java\javapath;;D:\PyCharm Community Edition 2018.3.5\bin;;.]
16-May-2019 15:36:55.334 INFO [main] org.apache.coyote.AbstractProtocol.init Initializing ProtocolHandler ["http-nio-8080"]
16-May-2019 15:36:55.343 INFO [main] org.apache.tomcat.util.net.NioSelectorPool.getSharedSelector Using a shared selector for servlet write/read
16-May-2019 15:36:55.355 INFO [main] org.apache.coyote.AbstractProtocol.init Initializing ProtocolHandler ["ajp-nio-8009"]
16-May-2019 15:36:55.357 INFO [main] org.apache.tomcat.util.net.NioSelectorPool.getSharedSelector Using a shared selector for servlet write/read
16-May-2019 15:36:55.357 INFO [main] org.apache.catalina.startup.Catalina.load Initialization processed in 381 ms
16-May-2019 15:36:55.372 INFO [main] org.apache.catalina.core.StandardService.startInternal Starting service [Catalina]
16-May-2019 15:36:55.372 INFO [main] org.apache.catalina.core.StandardEngine.startInternal Starting Servlet Engine: Apache Tomcat/8.5.39
16-May-2019 15:36:55.378 INFO [main] org.apache.coyote.AbstractProtocol.start Starting ProtocolHandler ["http-nio-8080"]
16-May-2019 15:36:55.384 INFO [main] org.apache.coyote.AbstractProtocol.start Starting ProtocolHandler ["ajp-nio-8009"]
16-May-2019 15:36:55.384 INFO [main] org.apache.catalina.startup.Catalina.start Server startup in 27 ms
Connected to server
[2019-05-16 03:36:55,667] Artifact SpringgMVC:war exploded: Artifact is being deployed, please wait...
16-May-2019 15:36:57.032 INFO [RMI TCP Connection(3)-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.
[2019-05-16 03:36:57,076] Artifact SpringgMVC:war exploded: Artifact is deployed successfully
[2019-05-16 03:36:57,077] Artifact SpringgMVC:war exploded: Deploy took 1 410 milliseconds
16-May-2019 15:37:05.382 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory [C:\Program Files\Apache Software Foundation\Tomcat 8.5\webapps\manager]
16-May-2019 15:37:05.442 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory [C:\Program Files\Apache Software Foundation\Tomcat 8.5\webapps\manager] has finished in [60] ms


Error is: Can not resolve servlet 'dispatcher'.

Pom.xml updated too above.

A: You can try maven tomcat plugin
<plugin>
   <groupId>org.apache.tomcat.maven</groupId>
   <artifactId>tomcat7-maven-plugin</artifactId>
    <version>2.2</version>
    <configuration>
         <port>9000</port>   //Configure port number
         <path>/spring5-webmvc-demo</path>   //Configure application root URL
    </configuration>
  </plugin>

Then you can do a build mvn clean install and then mvn tomcat7:run

A: At least I resolved my problem. As told M. Deinum I have moved an web.xml, view, and spring-mvc-demo-servlet.xml to WEB-INF, because I have:
<bean
        class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/view/" />
        <property name="suffix" value=".jsp" />
    </bean>

Then I regenerated an Artifacts.
