Spring 4中的錯誤| java.lang.ClassNotFoundException：org.springframework.web.servlet.DispatcherServlet

Question

我在執行spring 4應用程序時遇到錯誤，請您能幫我嗎？

java.lang.ClassNotFoundException：org.apache.catalina.loader.WebappClassLoader.loadClass（WebappClassLoader.java處的org.apache.catalina.loader.WebappClassLoader.loadClass（WebappClassLoader.java:1324）的org.springframework.web.servlet.DispatcherServlet ：1177），位於org.apache.catalina.core.DefaultInstanceManager.loadClassMaybePrivileged（DefaultInstanceManager.java:531），位於org.apache.catalina.core.DefaultInstanceManager.loadClass（DefaultInstanceManager.java:531），位於org.apache.catalina.core。 org的org.apache.catalina.core.StandardWrapper.loadServlet（StandardWrapper.java:1105）的DefaultInstanceManager.newInstance（DefaultInstanceManager.java:150）org的org.apache.catalina.core.StandardWrapper.load（StandardWrapper.java:1041） org.apache.catalina.core.StandardContext.startInternal（StandardContext.java:5218）（位於org.apache.catalina.util.LifecycleBase.start（LifecycleBase）處的.apache.catalina.core.StandardContext.loadOnStartup（StandardContext.java:4932） .java：150），位於org.apache.catalina.core.ContainerBase $ org.apache.catalina.core.ContainerBase $ StartChild.call（ContainerBase.java:1386）（位於java.util.concurrent.FutureTask.run（未知源）處的StartChild.call（ContainerBase.java:1396））。 java.util.concurrent中的current.ThreadPoolExecutor.runWorker（未知源）java.lang.Thread.run中的Thread.PoolExecutor $ Worker.run（未知源）

這是我的pom.xml

<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.anandc.webmvc</groupId>
    <artifactId>MVC_Test</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>war</packaging>
    <name>Spring4MVCWebApp</name>
    <url>http://maven.apache.org</url>
    <properties>
        <spring.version>4.0.5.RELEASE</spring.version>
        <freemarker.version>2.3.20</freemarker.version>
        <spring.security.version>3.2.3.RELEASE</spring.security.version>
        <spring.security.taglib.version>3.0.5.RELEASE</spring.security.taglib.version>
        <spring.jdbc.version>4.0.2.RELEASE</spring.jdbc.version>
        <common.logging.version>1.1.1</common.logging.version>
        <servlet.api.version>3.0.1</servlet.api.version>
        <jstl.version>1.2</jstl.version>        
    </properties>

    <dependencies>

        <!-- JUnit dependencies Start -->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>3.8.1</version>
            <scope>test</scope>
        </dependency>
        <!-- JUnit dependencies End -->

        <!-- FTL dependencies Start -->
        <dependency>
            <groupId>org.freemarker</groupId>
            <artifactId>freemarker</artifactId>
            <version>${freemarker.version}</version>
        </dependency>
        <!-- FTL dependencies End -->

        <!-- Spring dependencies Start -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context-support</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <!-- Spring dependencies End -->
        <!-- Spring Security Artifacts - START -->
        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-web</artifactId>
            <version>${spring.security.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-config</artifactId>
            <version>${spring.security.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-taglibs</artifactId>
            <version>${spring.security.taglib.version}</version>
        </dependency>
        <!-- Spring Security Artifacts - END -->

        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
            <version>${jstl.version}</version>
            <scope>compile</scope>
        </dependency>       
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>${servlet.api.version}</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>commons-logging</groupId>
            <artifactId>commons-logging</artifactId>
            <version>${common.logging.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>${spring.jdbc.version}</version>
        </dependency>

    </dependencies>

    <build>
        <sourceDirectory>src</sourceDirectory>
        <finalName>Spring4MVCWebApp</finalName>
        <plugins>
            <plugin>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.1</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>
            <plugin>
                <artifactId>maven-war-plugin</artifactId>
                <version>2.4</version>
                <configuration>
                    <warSourceDirectory>WebContent</warSourceDirectory>
                    <failOnMissingWebXml>false</failOnMissingWebXml>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

這就是我的web.xml的樣子

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xmlns="http://java.sun.com/xml/ns/javaee"
        xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
        xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
        id="WebApp_ID" version="3.0">

  <display-name>Freemarker_SpringMVC_example</display-name>
  <welcome-file-list>
    <welcome-file>index.html</welcome-file>
    <welcome-file>index.jsp</welcome-file>
  </welcome-file-list>

  <servlet>
        <servlet-name>spring</servlet-name>
        <servlet-class>
            org.springframework.web.servlet.DispatcherServlet
        </servlet-class>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>spring</servlet-name>
        <url-pattern>*.html</url-pattern>
    </servlet-mapping>
</web-app>

這就是我的spring-servlet.xml的樣子，

<?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:p="http://www.springframework.org/schema/p"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd                http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd">

    <!-- freemarker config -->
    <bean id="freemarkerConfig" class="org.springframework.web.servlet.view.freemarker.FreeMarkerConfigurer">
      <property name="templateLoaderPath" value="/WEB-INF/ftl/"/>
    </bean>

    <!--
      View resolvers can also be configured with ResourceBundles or XML files. If you need
      different view resolving based on Locale, you have to use the resource bundle resolver.
    -->
    <bean id="viewResolver" class="org.springframework.web.servlet.view.freemarker.FreeMarkerViewResolver">
      <property name="cache" value="true"/>
      <property name="prefix" value=""/>
      <property name="suffix" value=".ftl"/>
    </bean>

    <context:component-scan
        base-package="com.anandc" />

</beans>

另外，請提出在使用Spring 4時是否需要在POM中進行任何清理的建議。

先感謝您 ！

請注意-我已經解決了現有的類似問題，但是這些都無濟於事。

問候，
阿南德·查萬（Anand Chavan）

Answer 1

您可以嘗試：
1，更改spring-servlet.xml：

FROM    

<bean id="viewResolver" class="org.springframework.web.servlet.view.freemarker.FreeMarkerViewResolver">
  <property name="cache" value="true"/>
  <property name="prefix" value=""/>
  <property name="suffix" value=".ftl"/>
</bean>

TO <property name="prefix" value="/"/>

2，如果將jar放在庫中 ，則嘗試將這些jar放到WEB-INF / lib

我通過上面的方法解決了這個問題。
但是我真的不知道為什么。

Answer 2

嘗試以下技巧，每次都對我有用：

1. 選擇項目，然后轉到屬性>部署程序集
2. 點擊添加
3. 選擇Java構建路徑條目
4. 如果其中存在任何Maven依賴關系，請全選（Ctrl + A）並單擊“ 完成”。
5. 清理並刷新您的項目

發布並嘗試立即啟動服務器，

希望對您有幫助，最好的問候，