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

Question

请不要将此帖子标记为重复，因为我在相关问题中没有找到任何好的资源。

使用的技术：- Spring MVC 4.3.3.RELEASE Gradle 3.1 Tomcat 9.0

我创建了一个动态 Web 项目，当我运行它时，出现以下错误

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)

据说它找不到调度程序 servlet 类，但是当我ctrl + click spring-dispatcher-servlet的调度程序 servlet 路径时，它会到达 spring Dispatcher Servlet 类。 我无法找到这个问题的根本原因。

这是我的web.xml和spring-dispatcher-servlet.xml文件

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

我的gradle.build文件

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'

        }
        }

整个项目代码可以在https://github.com/viper-pranish/menu-order找到

项目结构内的依赖关系

Answer 1

你可以简单地在 web.xml 的标签下添加标签，它会起作用。

Answer 2

正如@Denium 指出的，你不应该混合使用 spring 版本

从 gradle.build 中删除compile group: 'org.springframework', name: 'spring', version: '3.2.0.RC1'并添加

apply plugin: 'war'

你也可以提供你的控制器 url 映射

<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. 添加 slf4j 依赖项。 问题将得到解决。 我的 pom.xml 依赖项解决了这个问题。

2. 添加slf4j后如果问题没有解决，再在Deployment Assembly中添加Maven Dependency。

Answer 5

很可能在 tomcat 启动时没有加载和部署必要的 Spring MVC 相关 jar 文件。 但请注意：这些文件位于您的类路径中，因此您在开发期间不会在 Eclipse IDE 中收到任何错误。 仅在运行时发生。 解决这个问题：- 1）右键单击项目 2）单击属性 3）单击部署程序集选项卡 4）单击添加 5）单击 Java 构建路径条目 6）单击 Maven 依赖项 7）单击完成 8）重新部署 Spring MVC 再次应用到 Tomcat 9)重启 Tomcat