使用Hibernate在Spring MVC中未將流發送到控制器

Question

這是emp-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"  
    xmlns:p="http://www.springframework.org/schema/p"  
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    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">  
   <context:component-scan base-package="com.cgi.controller"/>  
   <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
      <property name="prefix" value="/WEB-INF/JSPS/" />
      <property name="suffix" value=".jsp" />
   </bean>                  
   <bean id="ds" class="org.springframework.jdbc.datasource.DriverManagerDataSource">  
     <property name="driverClassName" value="com.mysql.jdbc.Driver" />  
     <property name="url" value="jdbc:mysql://localhost:3306/tutorial" />  
     <property name="username" value="root" />  
     <property name="password" value="tiger" />  
   </bean>  
   <bean id="mysessionFactory"  class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">  
     <property name="dataSource" ref="ds"></property>  
     <property name="mappingResources">  
       <list><value>Employee.hbm.xml</value></list>  
     </property>  
     <property name="hibernateProperties">  
       <props>  
         <prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop>  
         <prop key="hibernate.hbm2ddl.auto">update</prop>  
         <prop key="hibernate.show_sql">true</prop>     
       </props>  
     </property>  
    </bean> 
    <bean id="hibernateTemplate" class="org.springframework.orm.hibernate3.HibernateTemplate"> 
      <property name="sessionFactory" ref="mysessionFactory"/>
    </bean>
    <bean id="LoginDao" class="com.cgi.dao.LoginDaoImpl">  
       <property name="ht" ref="hibernateTemplate"></property>  
    </bean>  
</beans>  

這是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>Login Example</display-name>
  <welcome-file-list>
    <welcome-file>Login-Form.jsp</welcome-file>
  </welcome-file-list>
  <servlet>
    <servlet-name>emp</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>/WEB-INF/Controller-servlet.xml</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
  </servlet>
  <servlet-mapping>
    <servlet-name>emp</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>
  <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>/WEB-INF/emp-servlet.xml</param-value>
  </context-param>
  <listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
  </listener>
</web-app>

這是我的控制器包com.cgi.controller ;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.servlet.ModelAndView;

import com.cgi.beans.Employee;
import com.cgi.dao.LoginDaoImpl;

import java.util.*;

@Controller
public class EmployeeController
{
    LoginDaoImpl d;

    @RequestMapping(value="/Check", method=RequestMethod.POST)
    public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response) throws Exception 
    {
        String name=request.getParameter("username");
        String password=request.getParameter("pass");
        List<Employee> b=(List<Employee>) d.checkuser(name, password);
        System.out.println("Hello");
        Map m=new HashMap();
        m.put("msg", "Hello"+name);

        if(b.size()>0)
        {
            return new ModelAndView("Success",m);
        }
        else
        {
            return new ModelAndView("Fail");
        }
    }

    @RequestMapping(value="/GetAll", method = RequestMethod.POST)
    public ModelAndView getAll(HttpServletRequest request, HttpServletResponse response) throws Exception 
    {
        List<Employee> l=d.getall();

        Map m=new HashMap();
        m.put("msg", l);
        return new ModelAndView("AllUsers",m);
    }

    @RequestMapping("/Register.htm")
    public ModelAndView register(HttpServletRequest req, HttpServletResponse resp) throws Exception
    {
        ApplicationContext ax=new ClassPathXmlApplicationContext("emp-servlet.xml");

        Employee e=(Employee)ax.getBean("d");  
        d.save(e);

        return new ModelAndView("AllUsers");
    }
}

這是jsp文件

<%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Login Form</title>

</head>
<body>

<form method="post" action="/emp/Check"> 
<center>
<pre>

User-Name: <input id="name" type="text" name="username" required ><br>
Password:  <input id="pswd" type="password" name="pass" required><br>

<input type="submit" value="Submit"><br>

</pre>
</center>
</form> 
</body>
</html>

問題是，盡管我在web.xml具有正確的映射方案，但從jsp到我的控制器也沒有。 我檢查了我的網站，但它們都顯示相同的內容。 如果有人可以在其系統上運行它並進行檢查，請..請盡快還原。

錯誤報告 。

嚴重：路徑為[/ Employee_Management_Tool]的上下文中Servlet [emp]的Servlet.service（）拋出異常[請求處理失敗； 嵌套異常是java.lang.NullPointerException]，其根本原因是com.cgi.controller.EmployeeController.handleRequest（EmployeeController.java:28）處在com.cgi.controller.EmployeeController.handleRequest（EmployeeController.java:28）處，在sun.reflect處發生了java.lang.NullPointerException org.springframework.web.bind.annotation.support.HandlerMethodInvoker.doInvokeMethod上的java.lang.reflect.Method.invoke上的.NativeMethodAccessorImpl.invoke（未知源） （org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod（HandlerMethodInvoker.java:167）在org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod（AnnotationMethodHandlerAdapter.java ：414），位於org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle（AnnotationMethodHandlerAdapter.java:402），位於org.springframework.web.servlet.DispatcherServlet.doDispatc org.springframework.web.servlet.DispatcherServlet.doService（DispatcherServlet.java:716）處的org.springframework.web.servlet.FrameworkServlet.processRequest（FrameworkServlet.java:647）處的h（DispatcherServlet.java:771） .web.servlet.FrameworkServlet.doPost（FrameworkServlet.java:563）位於javax.servlet.http.HttpServlet.service（HttpServlet.java:648）位於javax.servlet.http.HttpServlet.service（HttpServlet.java:729）位於org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:206）上的org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:291）在org.apache.tomcat.websocket.server.WsFilter。 org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:239）處的doFilter（WsFilter.java:52）org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:206）處的org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:239） org.apache.catalina上的.catalina.core.StandardWrapperValve.invoke（StandardWrapperValve.java:212） org.apache.catalina.authenticator.AuthenticatorBase.invoke（AuthenticatorBase.java:502）上的.core.StandardContextValve.invoke（StandardContextValve.java:106）在org.apache.catalina.core.StandardHostValve.invoke（StandardHostValve.java:141上） ）的org.apache.catalina.valves.AbstractAccessLogValve.invoke（AbstractAccessLogValve.java:616）的org.apache.catalina.valves.AbstractAccessLogValve.invoke（AbstractAccessLogValve.java:616）的org.apache.catalina.core.StandardEngineValve。在org.apache處的org.apache.catalina.connector.CoyoteAdapter.service（CoyoteAdapter.java:521）處的invoke（StandardEngineValve.java:88）在org.apache.coyote.http11.AbstractHttp11Processor.process（AbstractHttp11Processor.java:1096）處.org.apache.tomcat.util.net.NioEndpoint的.coyote.AbstractProtocol $ AbstractConnectionHandler.process（AbstractProtocol.java:674）在org.apache.tomcat.util.net.NioEndpoint的$ SocketProcessor.doRun（NioEndpoint.java:1500） java.util.concurrent.ThreadPoolExecutor.runWorker上的$ SocketProcessor.run（NioEndpoint.java:1456）（未知S 在org.apache.tomcat.util.threads.TaskThread $ WrappingRunnable.run（TaskThread.java:61）處java.util.concurrent.ThreadPoolExecutor $ Worker.run（unknown Source）處（java.lang.Thread.run（來源不明）

Answer 1

1. 檢查您的jsp文件是否位於“ / WEB-INF / JSPS /”文件夾中。

2. 檢查您的web.xml，其中兩次提到“ contextConfigLocation”。 見下文

    <servlet> <servlet-name>emp</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>/WEB-INF/Controller-servlet.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> 

並再次具有另一個價值

  <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>/WEB-INF/emp-servlet.xml</param-value>
  </context-param>

我認為您應該刪除第二個，並用值“ /WEB-INF/emp-servlet.xml”更正第一個。

3. 在jsp'action =“ / emp / Check'中檢查您的操作，應該像'action = Check'