JDBC_apache的DBUtils核心代码

//domain层javaBean

package cn.code.dbUtils;

public class Stu {
    private String number;
    private String name;
    private int age;
    private String gender;
    public Stu() {
        super();
        // TODO Auto-generated constructor stub
    }
    public Stu(String number, String name, int age, String agender) {
        super();
        this.number = number;
        this.name = name;
        this.age = age;
        this.gender = agender;
    }
    public String getNumber() {
        return number;
    }
    public void setNumber(String number) {
        this.number = number;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }
    public String getGender() {
        return gender;
    }
    public void setGender(String agender) {
        this.gender = agender;
    }
    @Override
    public String toString() {
        return "Stu [number=" + number + ", name=" + name + ", age=" + age
                + ", gender=" + gender + "]";
    }
}

//工具类DBUtils

package cn.code.dbUtils;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import javax.sql.DataSource;


public class DBUtilsDemo {
    DataSource datasource;
    
    public DBUtilsDemo(DataSource datasource) {
        super();
        this.datasource = datasource;
    }
    public DBUtilsDemo() {
        super();
        // TODO Auto-generated constructor stub
    }
    public int update(String sql,Object...params){
        Connection con=null;
        PreparedStatement ps=null;
        try{
            //得到链接
            con= datasource.getConnection();
            //得到执行sql语句对象
            ps = con.prepareStatement(sql);
            //给sql语句传参赋值
            initparams(ps,params);
            //返回执行语句影响行数
            return ps.executeUpdate();
        }catch(Exception e){
            throw new RuntimeException(e);
        }finally{
            try{
                if(ps!=null)ps.close();
                if(con!=null)con.close();
            }catch(Exception e){
                throw new RuntimeException(e);
            }
                
        }
    }
    private void initparams(PreparedStatement ps, Object[] params) throws SQLException {
        for(int x=0;x<params.length;x++){
            ps.setObject(x+1, params[x]);
        }
        
    }
    public <T> T query(String sql,RsHandler<T> rh,Object...params){
        Connection con=null;
        PreparedStatement ps=null;
        ResultSet rs = null;
        try{
            //获取连接
            con= datasource.getConnection();
            //获取执行语句对象
            ps= con.prepareStatement(sql);
            //传递参数
            initparams(ps, params);
            //执行sql获取结果集
            rs = ps.executeQuery();
            //调用接口方法handler()将结果集映射成对象返回
            return rh.handler(rs);
        }catch(Exception e){
            throw new RuntimeException(e);
        }finally{
            try{
                if(ps!=null)ps.close();
                if(con!=null)con.close();
            }catch(Exception e){
                throw new RuntimeException(e);
            }
        }
    }

}

//接口

package cn.code.dbUtils;

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


public interface RsHandler<T> {
    public T handler(ResultSet rs)throws SQLException;
}

//测试类

package cn.code.dbUtils;

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

import org.junit.Test;

import cn.code.jdbc.JDBCUtils2;

public class Demo {
    @Test
    public void test(){
        Stu s = find("0001");
        System.out.println(s);
        //addStu();
    }
    public void addStu(){
        //创建对象给出连接池
        DBUtilsDemo dd = new DBUtilsDemo(JDBCUtils2.getDataSource());
        //给出sql模板
        String sql ="insert into stu values(?,?,?,?)";
        //给出参数
        Object[]params={"0001","zhouxingchi",55,"boy"};
        //执行增删改
        dd.update(sql, params);
    }
    public Stu find(String number){
        DBUtilsDemo dd = new DBUtilsDemo(JDBCUtils2.getDataSource());
        String sql ="select * from stu where number=?";
        Object[]params={number};
        //实现RsHandler接口，内部类
        RsHandler<Stu> rh = new RsHandler<Stu> (){

            @Override
            public Stu handler(ResultSet rs) throws SQLException {
                if(!rs.next())return null;
                Stu stu = new Stu();
                stu.setNumber(rs.getString("number"));
                stu.setName(rs.getString("name"));
                stu.setAge(rs.getInt("age"));
                stu.setGender(rs.getString("gender"));
                return stu;
            }
            
        };
        return (Stu)dd.query(sql, rh, params);
    }
}