DBUtils工具类的使用

亦凉 2022-05-21 12:52 269阅读 0赞

package com.baidu.test;  
  
  
import java.sql.SQLException;  
import java.util.List;  
  
  
import org.apache.commons.dbutils.QueryRunner;  
import org.apache.commons.dbutils.handlers.ArrayHandler;  
import org.apache.commons.dbutils.handlers.BeanHandler;  
import org.apache.commons.dbutils.handlers.BeanListHandler;  
import org.junit.Test;  
  
  
import com.baidu.pojo.EE;  
import com.baidu.utils.JDBCUtils;  
  
  
/\*\*  
 \*   
\* @ClassName: TestDButils   
\* <p>Description: 学习使用dbutils进行CRUD</p>  
  
public class TestDButils \{  
  
  
  
//查询所有  
@Test  
public void test1() throws SQLException\{  
  
/\*\*  
\* 第一种查询方式；要求实例化QueryRunner的时候，传入dataSource,执行sql的时候，不需要传递connection  
\*/  
  
// QueryRunner queryRunner = new QueryRunner(JDBCUtils.getDS());  
//查询  
// List<EE> list = queryRunner.query("select \* from ee", new BeanListHandler<>(EE.class));  
// for (EE ee : list) \{  
// System.out.println(ee);  
// \}  
  
  
/\*\*  
\* 第二种方式  
\*/  
QueryRunner queryRunner = new QueryRunner();  
List<EE> list = queryRunner.query(JDBCUtils.getConnection(),"select \* from ee", new BeanListHandler<>(EE.class));  
for (EE ee : list) \{  
System.out.println(ee);  
\}  
\}   
  
  
//返回单个对象  
@Test  
public void test2() throws SQLException\{  
QueryRunner queryRunner = new QueryRunner(JDBCUtils.getDS());  
EE ee = queryRunner.query("select \* from ee where id=1", new BeanHandler<>(EE.class));  
System.out.println(ee);  
  
  
\}  
  
//传递参数问题  
@Test  
public void test3() throws SQLException\{  
/\*\*  
\* 注意：返回结果的pojo的属性名称必须和列名保持一致  
\*/  
  
QueryRunner queryRunner = new QueryRunner(JDBCUtils.getDS());  
Object\[\] params=\{1,"aa"\};  
EE ee = queryRunner.query("select \* from ee where id=? and name=?",params, new BeanHandler<>(EE.class));  
System.out.println(ee);  
  
  
\}  
  
  
//增删改  
@Test  
public void test4() throws SQLException\{  
QueryRunner queryRunner = new QueryRunner(JDBCUtils.getDS());  
queryRunner.update("update ee set name=? where id=?", "admin",1);  
  
\}  
  
//获取总页数(终结版)  
@Test  
public void test5() throws SQLException\{  
QueryRunner queryRunner = new QueryRunner(JDBCUtils.getDS());  
Object\[\] query = queryRunner.query("select count(\*) from ee", new ArrayHandler());  
System.out.println(query\[0\]);  
  
\}  
  
  
\}