JavaWeb网上图书商城完整项目-数据库操作工具类2-MapHandle的高级用法

1、现在在上面一章的基础上,我们引入一个address表,该表记录person类的地址,address表的格式如下所示

现在person类要和address表想关联,得到当前联系人的住宅地址,我们应该在person表中增加一个aid的字段,aid的值来自于address中

 现在我们执行下面的操作:

我们如何通过代码把上面的结果集选择出来了。

可以使用MapHandle类来实现

我们来看下面的代码:

package com.weiyuan.test;

public class Address {
    private int aid;
    private String province;
    private String city;
    private String district;
    private String street;
    public int getAid() {
        return aid;
    }
    public void setAid(int aid) {
        this.aid = aid;
    }
    public String getProvince() {
        return province;
    }
    public void setProvince(String province) {
        this.province = province;
    }
    public String getCity() {
        return city;
    }
    public void setCity(String city) {
        this.city = city;
    }
    public String getDistrict() {
        return district;
    }
    public void setDistrict(String district) {
        this.district = district;
    }
    public String getStreet() {
        return street;
    }
    public void setStreet(String street) {
        this.street = street;
    }
    @Override
    public String toString() {
        return "Address [aid=" + aid + ", province=" + province + ", city="
                + city + ", district=" + district + ", street=" + street + "]";
    }
    
    
    

}
package com.weiyuan.test;

public class Person {
    private String pid;
    private String pname;
    private int age;
    private String sex;
    private Address address;
    public String getPid() {
        return pid;
    }
    public void setPid(String pid) {
        this.pid = pid;
    }
    public String getPname() {
        return pname;
    }
    public void setPname(String pname) {
        this.pname = pname;
    }
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
package com.weiyuan.test;

import java.sql.SQLException;
import java.util.List;
import java.util.Map;

import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanHandler;
import org.apache.commons.dbutils.handlers.BeanListHandler;
import org.apache.commons.dbutils.handlers.MapHandler;
import org.apache.commons.dbutils.handlers.MapListHandler;
import org.apache.commons.dbutils.handlers.ScalarHandler;
import org.junit.Test;
import org.junit.runner.RunWith;

import cn.itcast.commons.CommonUtils;
import cn.itcast.jdbc.JdbcUtils;
import cn.itcast.jdbc.TxQueryRunner;

/**
 * 对数据库操作类的测试
 * */
public class TxRunnerTest {

    
    
    @Test
    public void testQuery6() throws SQLException{
        /*
         * map ={sex=男, street=肖家河街道6号, age=20, province=四川省, pname=张三, pid=2, aid=1, district=武侯区, city=成都市}
         * */
        QueryRunner run = new TxQueryRunner();
        String sql = "select * from person p, address a where p.aid=a.aid and p.pid = ?";
        Map<String,Object> map= run.query(sql,new MapHandler(),"2");
        Person p = CommonUtils.toBean(map, Person.class);
        Address address = CommonUtils.toBean(map, Address.class);
        p.setAddress(address);
        System.out.println(map);
        
    }
}


this.age = age;
    }
    public String getSex() {
        return sex;
    }
    public void setSex(String sex) {
        this.sex = sex;
    }
    @Override
    public String toString() {
        return "Person [pid=" + pid + ", pname=" + pname + ", age=" + age
                + ", sex=" + sex + ", address=" + address + "]";
    }
    public Address getAddress() {
        return address;
    }
    public void setAddress(Address address) {
        this.address = address;
    }
    
    
    
    

}
原文地址:https://www.cnblogs.com/kebibuluan/p/6779477.html