Spring使用JdbcTemplate操作数据库---使用RowMapperResultSetExtractor读数据篇

首先建立数据表：

CREATE TABLE `login` (
  `username` varchar(10) default NULL,
  `passwd` varchar(10) default NULL,
  `address` varchar(10) default NULL
) ENGINE=InnoDB DEFAULT CHARSET=gb2312;

 

配置文件：

 

xml version="1.0" encoding="UTF-8" ?>
DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd"  >
< beans >
  < bean  id ="dataSource"  class ="org.apache.commons.dbcp.BasicDataSource" >
    < property  name ="driverClassName" >
      < value > com.mysql.jdbc.Driver value >
    property >
    < property  name ="url" >
      < value > jdbc:mysql://localhost:3306/javaee value >
    property >
    < property  name ="username" >
      < value > root value >
    property >
    < property  name ="password" >
      < value > 1234 value >
    property >
  bean >
  < bean  id ="jdbcTemplate"  class ="org.springframework.jdbc.core.JdbcTemplate" >
    < property  name ="dataSource" >
      < ref  local ="dataSource" />
    property >
  bean >

< bean  id ="personDAO"  class ="SpringJDBCSupport.ReadData.PersonDAO" >
   < property  name ="jdbcTemplate" >
     < ref  local ="jdbcTemplate" />
   property >
bean >  
beans >

 JavaBean

 

package  SpringJDBCSupport.ReadData;
import  com.mysql.jdbc.Driver;
public   class  Person  ... {
  private String name;
  private String password;
  private String address;
  public Person()...{
      
  }
  public Person(String name,String password,String address)...{
      this.name=name;
      this.password=password;
      this.address=address;
  }
public String getAddress() ...{
    return address;
}
public void setAddress(String address) ...{
    this.address = address;
}
public String getName() ...{
    return name;
}
public void setName(String name) ...{
    this.name = name;
}
public String getPassword() ...{
    return password;
}
public void setPassword(String password) ...{
    this.password = password;
}
public String toString()...{
    return this.getName()+"-"+this.getPassword()+"-"+this.getAddress();
}
}

 

编写自定义RowMapper

 

package  SpringJDBCSupport.ReadData;

import  java.sql.ResultSet;
import  java.sql.SQLException;

import  org.springframework.jdbc.core.RowMapper;

public   class  PersonRowMapper  implements  RowMapper  ... {

    public Object mapRow(ResultSet rs, int index) throws SQLException ...{
        Person person=new Person();
        person.setName(rs.getString("username"));
        person.setPassword(rs.getString("passwd"));
        person.setAddress(rs.getString("address"));
        return person;
    }

}

 

测试代码：

 

package  SpringJDBCSupport.ReadData;

import  java.io.File;
import  java.util.ArrayList;
import  java.util.Iterator;
import  java.util.List;

import  org.springframework.beans.factory.BeanFactory;
import  org.springframework.beans.factory.xml.XmlBeanFactory;
import  org.springframework.core.io.FileSystemResource;

public   class  TestJDBCTemplate  ... {

    public static String filePath="";
    public static BeanFactory factory=null;
    public static void main(String[] args) ...{
        filePath=System.getProperty("user.dir")+File.separator+"SpringJDBCSupport"+File.separator+"ReadData"+File.separator+"hello.xml";
        factory=new XmlBeanFactory(new FileSystemResource(filePath));
        PersonDAO personDAO=(PersonDAO)factory.getBean("personDAO");
        /**//*
         * 准备数据
         */
        Person p1=new Person("test1","test1","test1");
        Person p2=new Person("test2","test2","test2");
        Person p3=new Person("test3","test3","test3");
        Person p4=new Person("test4","test4","test4");
        Person p5=new Person("test5","test5","test5");
        List persons=new ArrayList();
        persons.add(p3);
        persons.add(p4);
        persons.add(p5);
        //使用jdbcTemplate.update方式
        personDAO.insertPersonUseUpdate(p1);
        //使用jdbcTemplate.execute方式
        personDAO.insertPersonUseExecute(p2);
    //    //使用jdbcTemplate批处理方式
        personDAO.updatePersonUseBatchUpdate(persons);
        
        //使用RowCallbackHandler执行一次查询,并打印person信息
        System.out.println(personDAO.getPersonByRowCallbackHandler("test1"));
        List a=personDAO.getPersonsByMapperResultReader();
        for (Iterator iter = a.iterator(); iter.hasNext();) ...{
            System.out.println((Person)iter.next());
            
        }
    }
    
    

}

 

运行程序：输出为以下结果，红色部分为查询结果集

test1-test1-test1
test1-test1-test1
test2-test2-test2
test3-test3-test3
test4-test4-test4
test5-test5-test5

我们完全可以用这个方法代替RowCallbackHandler，用一个自定义的RowMapper结局单个查询和结果集查询两种方式，返回单个对象是，只要修改

List result=(ArrayList)this.getJdbcTemplate().query(sql,params,new RowMapperResultSetExtractor(new PersonRowMapper()));
return result.get(0);
}

即可