Question

首先，这是我第一次尝试春天。使用spring的JDBC模板连接到数据库时遇到问题

这是我的AddEmployee Servlet代码：

package com.lftechnology.spring.jdbctemplate.controller;

import java.io.IOException;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.lftechnology.spring.jdbctemplate.model.dao.EmployeeDAO;
import com.lftechnology.spring.jdbctemplate.model.dao.EmployeeDAOImpl;
import com.lftechnology.spring.jdbctemplate.model.dao.mysql.EmployeeMySql;
import com.lftechnology.spring.jdbctemplate.model.dto.Employee;

@WebServlet("/AddEmployee")
public class AddEmployee extends HttpServlet 
{
    private static final long serialVersionUID = 1L;


    Employee employee;


    public AddEmployee() {
        super();

    }


    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException 
    {

        RequestDispatcher dispatcher=request.getRequestDispatcher("addemployee.jsp");
        dispatcher.forward(request, response);
    }


    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException 
    {

        ApplicationContext context=new ClassPathXmlApplicationContext("spring.xml");

        EmployeeDAO employeeDAO= (EmployeeDAO) context.getBean("employeeDAO");

       employee=new Employee();
       String name=(String) request.getAttribute("name");
       String designation=(String) request.getAttribute("designation");

       employee.setName(name);
       employee.setDesignation(designation);

       employeeDAO.insert(employee);

       RequestDispatcher dispatcher =request.getRequestDispatcher("success.jsp");
       dispatcher.forward(request,response);

    }

}

用于JDBC连接的名为EmployeeMySql的对应类是

package com.lftechnology.spring.jdbctemplate.model.dao.mysql;

import java.sql.SQLException;

import javax.sql.DataSource;

import org.springframework.jdbc.core.JdbcTemplate;

import com.lftechnology.spring.jdbctemplate.model.dao.EmployeeDAO;
import com.lftechnology.spring.jdbctemplate.model.dto.Employee;

public class EmployeeMySql extends JdbcTemplate implements EmployeeDAO
{

    private DataSource dataSource;




    public void setDataSource(DataSource dataSource) 
    {
        System.out.println("Datasource here"+dataSource.toString());
        try {
            System.out.println("Datasource here"+dataSource.getLoginTimeout());
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        this.dataSource = dataSource;
    }

    public void insert(Employee employee)
    {
        String query_sql;
        query_sql="INSERT INTO EMPLOYEE (name,designation) VALUES (?,?,?)";

        update(query_sql,new Object[]{employee.getName(),employee.getDesignation()});
    }

    @Override
    public Employee retrieveAllData() {
        // TODO Auto-generated method stub
        return null;
    }



}

类似地，我的spring bean配置是spring.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:aop="http://www.springframework.org/schema/aop"

xmlns:tx="http://www.springframework.org/schema/tx"

xsi:schemaLocation="http://www.springframework.org/schema/beans

                           http://www.springframework.org/schema/beans/spring-beans-2.0.xsd

                           http://www.springframework.org/schema/tx

                           http://www.springframework.org/schema/tx/spring-tx-2.0.xsd

                           http://www.springframework.org/schema/aop

                           http://www.springframework.org/schema/aop/spring-aop-2.0.xsd">


<bean id="dataSourcee" 
         class="org.springframework.jdbc.datasource.DriverManagerDataSource">

        <property name="driverClassName" value="com.mysql.jdbc.Driver" />
        <property name="url" value="jdbc:mysql://localhost:3306/spring" />
        <property name="username" value="root" />
        <property name="password" value="" />
    </bean>

<bean id="employeeDAO" class="com.lftechnology.spring.jdbctemplate.model.dao.mysql.EmployeeMySql">
   <property name="dataSource" ref="dataSourcee"/>
</bean>
<!-- import resource="Spring-Datasource.xml" />
    <import resource="Spring-Customer.xml" /-->


</beans>

然而，我总是最终得到一个我根本无法弄清楚的错误。我得到的错误是

HTTP Status 500 - Error creating bean with name 'employeeDAO' defined in class path resource [spring.xml]: Invocation of init method failed; nested exception is java.lang.IllegalArgumentException: Property 'dataSource' is required

type Exception report

message Error creating bean with name 'employeeDAO' defined in class path resource [spring.xml]: Invocation of init method failed; nested exception is java.lang.IllegalArgumentException: Property 'dataSource' is required

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

exception

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'employeeDAO' defined in class path resource [spring.xml]: Invocation of init method failed; nested exception is java.lang.IllegalArgumentException: Property 'dataSource' is required
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1455)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:519)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456)
    org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:294)
    org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:225)
    org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:291)
    org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193)
    org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:605)
    org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:925)
    org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:472)
    org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:139)
    org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:83)
    com.lftechnology.spring.jdbctemplate.controller.AddEmployee.doPost(AddEmployee.java:46)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:647)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:728)

root cause

java.lang.IllegalArgumentException: Property 'dataSource' is required
    org.springframework.jdbc.support.JdbcAccessor.afterPropertiesSet(JdbcAccessor.java:134)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1514)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1452)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:519)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456)
    org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:294)
    org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:225)
    org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:291)
    org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193)
    org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:605)
    org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:925)
    org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:472)
    org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:139)
    org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:83)
    com.lftechnology.spring.jdbctemplate.controller.AddEmployee.doPost(AddEmployee.java:46)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:647)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:728)

有人能告诉我错误是什么吗？非常感谢帮助。

Answer 1

在setDataSource方法中，调用super.setDataSource。您有自己的dataSource变量，但是，基类也使用给定的dataSource实例进行一些初始化，这就是错过的。

使用spring连接数据库时出错

1 个答案: