HTTP 状态 500 - 实例化 servlet 类 org.springframework.web.servlet.DispatcherServlet 时出错

Question

Please don't flag this post as a duplicate one because I didn't find any good resource in the relevant question.

Technologies used :- Spring MVC 4.3.3.RELEASE Gradle 3.1 Tomcat 9.0

I created a dynamic web project and when I run it, I get the following error

HTTP Status 500 - Error instantiating servlet class org.springframework.web.servlet.DispatcherServlet

type Exception report

message Error instantiating servlet class org.springframework.web.servlet.DispatcherServlet

description The server encountered an internal error that prevented it from fulfilling this request.

exception

javax.servlet.ServletException: Error instantiating servlet class org.springframework.web.servlet.DispatcherServlet
    org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:522)
    org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
    org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:620)
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:349)
    org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:1102)
    org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
    org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:788)
    org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1485)
    java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    java.lang.Thread.run(Thread.java:745)
root cause

java.lang.ClassNotFoundException: org.springframework.web.servlet.DispatcherServlet
    org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1299)
    org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1133)
    org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:522)
    org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
    org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:620)
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:349)
    org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:1102)
    org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
    org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:788)
    org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1485)
    java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    java.lang.Thread.run(Thread.java:745)

It is saying that it could not find the dispatcher servlet class but when I ctrl + click the dispatcher servlet path in the spring-dispatcher-servlet , It lands to the spring Dispatcher Servlet class. I could not get the root cause of this problem.

Here are my web.xml and spring-dispatcher-servlet.xml files

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>MenuOrder</display-name>

  <welcome-file-list>
    <welcome-file>index.jsp</welcome-file>
  </welcome-file-list>

  <servlet>
    <servlet-name>spring-dispatcher</servlet-name>
    <servlet-class>
        org.springframework.web.servlet.DispatcherServlet
    </servlet-class>
  </servlet>

  <servlet-mapping>
    <servlet-name>spring-dispatcher</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>

</web>

spring-dispatcher-servlet.xml

<?xml version="1.0" encoding="UTF-8"?>

<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.springframework.org/schema/beans 
    http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">

    <bean id = "HandlerMapping" class = "org.springframework.web.servlet.handler.BeanNameUrlHandlerMapping"/>

    <bean id = "viewResolver" 
        class = "org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name = "prefix">
            <value>/WEB-INF/</value>
        </property>

        <property name = "sufix">
            <value>.jsp</value>
        </property>
        </bean>

</beans>

Project directory

My gradle.build file

allprojects{
apply plugin: 'java'
apply plugin: 'eclipse-wtp'
group = 'com'
version = '0.0.1-SNAPSHOT'
}

subprojects{
    tasks.withType(JavaCompile){
    options.encoding = 'UTF-8'
    }
}



allprojects {
    task hello { task -> println "I'm $task.project.name" }
}


allprojects{

repositories {
    mavenLocal()
    jcenter()
    mavenCentral()

}


    dependencies {

        // The production code uses the SLF4J logging API at compile time
    //    compile 'org.slf4j:slf4j-api:1.7.21'


        //spring web
        compile group: 'org.springframework', name: 'spring-webmvc', version: '4.3.3.RELEASE'

        // spring core
        compile group: 'org.springframework', name: 'spring-core', version: '4.3.3.RELEASE'

        // spring context support
        compile group: 'org.springframework', name: 'spring-context-support', version: '4.3.3.RELEASE'


        // ORM dependencies

        // spring jpa
        compile group: 'org.springframework.data', name: 'spring-data-jpa', version: '1.10.4.RELEASE'

        // hibernate-entity manager
        compile group: 'org.hibernate', name: 'hibernate-entitymanager', version: '5.2.2.Final'

        // End of ORM dependencies

        // postgres connector
        compile group: 'org.postgresql', name: 'postgresql', version: '9.4-1200-jdbc41'

        // Junit
        compile group: 'junit', name: 'junit', version: '4.12'

        // servlet
        compile group: 'javax.servlet', name: 'javax.servlet-api', version: '4.0.0-b01'

        compile group: 'javax.el', name: 'javax.el-api', version: '2.2.1'

        compile group: 'org.springframework', name: 'spring', version: '3.2.0.RC1'

        }
        }

The whole project code can be found in https://github.com/viper-pranish/menu-order

Dependencies inside the project structure

Answer 1

you can simply add tag under tag of web.xml, It will work.

Answer 2

as @Denium pointed out you should not mix the spring versions

remove compile group: 'org.springframework', name: 'spring', version: '3.2.0.RC1' from gradle.build and add

apply plugin: 'war'

and you may to provide your controller url mapping as well

<bean name="/index"
            class="com.mkyong.common.controller.IndexController" />

Answer 3

确保您已在两个位置添加了所有必需的 Spring jar：在构建路径以及 WEB-INF/lib 文件夹中

Answer 4

<dependencies>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>4.1.7.RELEASE</version>
            <exclusions>
                <exclusion>
                    <artifactId>commons-logging</artifactId>
                    <groupId>commons-logging</groupId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
            <version>1.2</version>
        </dependency>


        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>

        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>jcl-over-slf4j</artifactId>
            <version>1.7.12</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-web</artifactId>
            <version>4.0.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-config</artifactId>
            <version>4.0.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-taglibs</artifactId>
            <version>4.0.2.RELEASE</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.springframework/spring-web -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>4.1.7.RELEASE</version>
        </dependency>

    </dependencies>

1. Add slf4j dependencies. The problem will resolve. My pom.xml dependencies it resolved the problem.

2. After adding slf4j if the problem is not resolved, then add Maven Dependency in Deployment Assembly.

Answer 5

Most probably the necessary Spring MVC related jar files are not loaded and deployed on tomcat startup. But note: these files are in your classpath and hence you are not getting any error in Eclipse IDE during development time. Happens only during runtime. to fix this:- 1)Right-click on project 2)Click on Properties 3)Click on Deployment Assembly Tab 4)Click Add 5)Click on Java Build Path Entries 6)Click on Maven Dependencies 7)Click Finish 8)Redeploy Spring MVC application to Tomcat again 9)Restart Tomcat