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dbutils是怎么使用

dbutils只是一个工具类，主要使用到QueryRunner、ResultSetHandler这两个类。 而QueryRunner主要使用到的是

1.query方法，是用来做查询的

2.update方法，用来做增删改操作

3.batch方法，用来做批处理

而ResultSetHandley则是可以理解为接收结果的

代码

package cn.bl.v4_DataSource.DBUtils;

import java.util.List; import java.util.Map;

import org.apache.commons.dbutils.QueryRunner; import org.apache.commons.dbutils.handlers.BeanListHandler; import org.apache.commons.dbutils.handlers.MapListHandler; import org.junit.Test;

import cn.bl.bean.Stud; import cn.bl.v4_DataSource.c3p0.C3P0Utils;

public class Demo1 {

//查询 - 将结果封装为List<Map<String,Object>> @Test public void testQuery1() throws Exception { QueryRunner runner = new QueryRunner(C3P0Utils.getDataSource()); List<Map<String, Object>>list = runner.query(" select * from car ",new MapListHandler() ); System.out.println(list); //[{price=23456.22, cname=奔驰, pid=1, id=1}, {price=23456.22, cname=马萨拉蒂, pid=2, id=2}, {price=23456.22, cname=法拉利, pid=3, id=3}, {price=23456.22, cname=劳斯莱斯, pid=4, id=4}, {price=23456.22, cname=三菱, pid=1, id=5}, {price=23456.22, cname=丰田, pid=2, id=6}, {price=23456.22, cname=本田, pid=2, id=7}, {price=23456.22, cname=QQ, pid=4, id=8}, {price=12.0, cname=迈巴赫, pid=3, id=11}] } //查询 - 封装为一个List<Student> @Test public void testQuery2() throws Exception { QueryRunner runner = new QueryRunner(C3P0Utils.getDataSource()); List<Stud> list = runner.query(" select * from stud", new BeanListHandler<>(Stud.class)); System.out.println(list); //[Stud [id=1, name=xlh, age=12, sex=0], Stud [id=2, name=xlhh, age=22, sex=0], Stud [id=3, name=阿斯蒂芬, age=30, sex=2], Stud [id=5, name=alice, age=20, sex=0], Stud [id=4, name=雷神, age=23, sex=0], Stud [id=23, name=雷神啊, age=21, sex=1], Stud [id=14, name=电神, age=12, sex=1], Stud [id=24, name=神仙, age=23, sex=1], Stud [id=39, name=小梨花, age=17, sex=1], Stud [id=50, name=张飞, age=30, sex=1], Stud [id=49, name=刘备, age=34, sex=1], Stud [id=52, name=张飞, age=30, sex=1], Stud [id=53, name=张飞, age=30, sex=1]] }

} package cn.bl.v4_DataSource.DBUtils;

import java.sql.Connection; import java.sql.SQLException; import java.util.Random;

import org.apache.commons.dbutils.QueryRunner; import org.junit.Test;

import cn.bl.v4_DataSource.c3p0.C3P0Utils;

public class Demo2 {

@Test public void testUpdate() throws Exception { QueryRunner runner = new QueryRunner(C3P0Utils.getDataSource()); int i = runner.update(" insert into stud(id,name,age,sex) values(50,'张飞',30,'1')"); System.out.println(i); i = runner.update(" insert into stud(id,name,age,sex) values(?,?,?,?)", 49,"刘备",34,"1"); System.out.println(i); } @Test public void testBatch() throws SQLException { QueryRunner runner = new QueryRunner(C3P0Utils.getDataSource()); Random r = new Random(); for(int i = 1;i<=100;i++) { Object[][]objects = new Object[][]{ {"Tom"+i,r.nextInt(20)+10}, {"小李子"+i,r.nextInt(20)+10}, {"Nancy"+i,r.nextInt(20)+10} }; runner.batch(" insert into student(sname,age) values(?,?)",objects); } } /* * 测试事务处理 */ @Test public void testTx() { QueryRunner runner = new QueryRunner(); Connection conn = C3P0Utils.getConnection(); try { conn.setAutoCommit(false); String sql = " insert into stud(id,name,age,sex) values(52,'张飞',30,'1') "; runner.update(conn, sql); sql = " insert into stud(id,name,age,sex) values(53,'张飞',30,'1') "; runner.update(conn, sql); conn.commit(); System.out.println("事务提交了..."); } catch (SQLException e) { System.out.println("事务回滚..."); try { conn.rollback(); } catch (SQLException e1) { e1.printStackTrace(); } e.printStackTrace(); } finally { try { conn.setAutoCommit(true); conn.close(); } catch (SQLException e) { e.printStackTrace(); } } }

}