我曾尝试使用下面的命令创建了一个示例Maven项目:无法实例化一个servlet,让类未发现异常
MVN原型:产生-DgroupId = com.rohit -DartifactId = RohitLoginApp -DarchetypeArtifactId = Maven的原型-webapp -DinteractiveMode =假
下面是项目结构的Eclipse中的图像的链接:
Maven project structure in eclipse
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/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.rohit</groupId>
<artifactId>RohitLoginApp</artifactId>
<packaging>war</packaging>
<version>1.0-SNAPSHOT</version>
<name>RohitLoginApp Maven Webapp</name>
<url>http://maven.apache.org</url>
<dependencies>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.0.1</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<finalName>RohitLoginApp</finalName>
</build>
</project>
的web.xml:
<!DOCTYPE web-app PUBLIC
"-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
"http://java.sun.com/dtd/web-app_2_3.dtd" >
<web-app>
<display-name>Archetype Created Web Application</display-name>
<servlet>
<servlet-name>RohitTestServlet</servlet-name>
<display-name>RohitTestServlet</display-name>
<description></description>
<servlet-class>com.company.rohit.RohitTestServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>RohitTestServlet</servlet-name>
<url-pattern>/RohitTestServlet</url-pattern>
</servlet-mapping>
</web-app>
RohitTestServlet.java
package com.company.rohit;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* Servlet implementation class RohitTestServlet
*/
public class RohitTestServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#HttpServlet()
*/
public RohitTestServlet() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
String userId = request.getParametker("userName");
String pwd = request.getParametker("psw");
response.getWriter().write("User ID and password are received");
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
}
}
的index.jsp
<html>
<body>
<h2>Login Page</h2>
<form action="RohitTestServlet">
User Name<br>
<input type="text" name="userName">
<br>
Password<br>
<input type="password" name="psw">
<br><br>
<input type="submit" value="Submit">
</form>
</body>
</html>
当我在tomcat上部署此应用程序时,它首先加载欢迎屏幕,我在其中输入用户名和密码,然后单击提交按钮。然后它重定向到servlet url,即http://localhost:8080/RohitLoginApp/RohitTestServlet?userName=“xyz”& psw =“www”。然而它无法击中servlet并获得响应。下面是错误:
严重:分配例外的servlet RohitTestServlet 抛出java.lang.ClassNotFoundException:com.company.rohit.RohitTestServlet 在org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1856 ) at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1705) at org.apache.catalina.core.DefaultInstanceManager.loadClass(DefaultInstanceManager.java:506) at org.apache.catalina.core .DefaultInstanceManager.loadClassMaybePrivileged(DefaultInstanceManager.java:488) at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:115) at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1148) at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:864) at org.apache.catalina.core。 StandardWrapperValve.invoke(StandardWrapperValve.java:134) 在org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122) 在org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:505) 在org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169) 在org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) 在org.apache.catalina.valves。 AccessLogValve.invoke(AccessLogValve.java:956) at org.apache.catalina.core.StandardEngineValve.invo科(StandardEngineValve.java:116) 在org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:423) 在org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1079) 在org.apache.coyote.AbstractProtocol $ AbstractConnectionHandler.process(AbstractProtocol.java:625) at org.apache.tomcat.util.net.JIoEndpoint $ SocketProcessor.run(JIoEndpoint.java:318) at java.util.concurrent。的ThreadPoolExecutor。runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor $ Worker.run(ThreadPoolExecutor.java:615) at org.apache.tomcat.util.threads.TaskThread $ WrappingRunnable.run(TaskThread.java: (Thread.java:745)
它无法加载类。我已经做了很多次,但仍然无法加载servlet。
您在'request.getParametker()'中有一个拼写错误' – Krzysiek
您是否尝试过在包资源管理器中右键单击项目并选择Maven - > Update Project(Alt + F5)? 然后转到服务器选项卡,展开Tomcat实例并从那里删除您的项目。之后,点击运行.. - >在服务器上运行 – Krzysiek