前面已经有文章说了DBUtils的一些特性, 这里再来详细说下QueryRunner的一些内部实现, 写的有错误的地方还恳请大家指出. ...QueryRunner类 QueryRunner中提供对sql语句操作的API 它主要有三个方法 query() 用于执行select update() 用于执行insert/update/delete...(QueryRunner qr = new QueryRunner(C3P0Utils.getDataSource())) query(sql,ResultSetHandler,Object...params...; list.add(maxprice); } QueryRunner qr = new QueryRunner(C3P0Utils.getDataSource...//批量删除 public void delBooks(String[] ids) throws SQLException { QueryRunner qr = new QueryRunner(
一.QueryRunner类实现增删改 连接池代码：JdbcUtil.java package com.wb.util; /** * c3p0,dbcp,druid */ import java.io.IOException...类对象 QueryRunner qr = new QueryRunner(); String sql = "UPDATE gjp_ledger set money=? ...; //结果集处理方式，ArrayHandler 第一行转成对象数组 QueryRunner qr = new QueryRunner(); Object[] objects = qr.query... qr = new QueryRunner(); Map map = qr.query(conn, sql,new MapHandler()); for(String ... qr = new QueryRunner(); List> list = qr.query(conn, sql,new MapListHandler());
C3P0Util 的制作 及DButils 中的 QueryRunner 类的使用 步骤: 导入jar 包 c3p0-0.9.1.2.jar commons-dbutils-1.4.jar...cn.javabs.test; import java.sql.SQLException; import java.util.List; import org.apache.commons.dbutils.QueryRunner...cn.javabs.entity.User; import cn.javabs.util.C3p0Util; /** * 数据源连接池的测试类 * @author Mryang * 本类中引入了一个新的工具类是 QueryRunner...*/ public class DataTest { QueryRunner qr = new QueryRunner(C3p0Util.getDataSource()); @Test public
1：DBUtils中的QueryRunner的使用： 1.1：QueryRunner中提供了对SQL语句操作的api； 1.2：主要有三个方法： 1.2.1：query()：用于执行select...（查询）； 1.2.2：update()：用于执行insert（插入）/update（更新）/delete（删除）； 1.2.3：batch()：批处理； 2：c3p0和QueryRunner..."; 49 try { 50 //使用QueryRunner的强大之处在于此处。...getQueryRunner(){ 28 //第一步：创建QueryRunner对象，传入连接池对象 29 //在创建QueryRunner对象的时候，如果传入数据对象...dataSource， 30 //那么在使用QueryRunner对象的方法时候，就不需要传入连接对象 31 QueryRunner query=new QueryRunner
QueryRunner类有四个重载的构造方法，如果使用QueryRunner(DataSource ds)构造QueryRunner对象，数据库事务将交给DBUtils框架进行管理，默认情况下每一个sql...如果使用QueryRunner()构造QueryRunner对象，就需要自己来管理事务，因为框架没有连接池，无法获得数据库的连接，此时应该使用带Connection参数的方法。...对象 QueryRunner queryRunner = new QueryRunner(dataSource); //2、准备方法参数 String sql ="insert into account...; QueryRunner queryRunner = new QueryRunner(dataSource); queryRunner.update(sql1,money,outAccount...; //手动事务管理 QueryRunner queryRunner = new QueryRunner(); Connection conn = JDBCUtils.getConnection
创建QueryRunner 的实现类 QueryRunner queryRunner = new QueryRunner(); // 2....()的返回值取决于handle的返回值 public class DBUtilsTest { QueryRunner queryRunner = new QueryRunner(); /...queryRunner = new QueryRunner(); Connection connection = null; String sql = "select...queryRunner = new QueryRunner(); Connection connection = null; String sql = "select...queryRunner = new QueryRunner(); Connection connection = null; String sql = "select
二、DBUtils的三个核心对象 QueryRunner类 ResultSetHandler接口 DBUtils类 QueryRunner类 QueryRunner中提供对sql语句操作的API...对象 20 QueryRunner qr = new QueryRunner(C3P0Util.getDataSource()); 21 List list...对象 46 QueryRunner qr = new QueryRunner(C3P0Util.getDataSource()); 47 // 执行查询语句，并返回结果...对象 43 QueryRunner qr = new QueryRunner(C3P0Util.getDataSource()); 44 qr.update("update...对象 50 QueryRunner qr = new QueryRunner(C3P0Util.getDataSource()); 51 qr.update("delete
创建QueryRunner对象 QueryRunner queryRunner = new QueryRunner(dataSource); //4....创建QueryRunner对象 QueryRunner queryRunner = new QueryRunner(dataSource); //4....创建QueryRunner对象 QueryRunner queryRunner = new QueryRunner(dataSource); //4....创建QueryRunner对象 QueryRunner queryRunner = new QueryRunner(dataSource); //4.执行SQL语句，将结果封装到 POJO...创建QueryRunner对象 QueryRunner queryRunner = new QueryRunner(dataSource); //4.执行SQL语句 // 查询一条数据
DBUtils ---- commons-dbutils是Apache组织提供的一个开源JDBC工具类库，封装了针对于数据库的增删改查操作 API QueryRunner ResulSetHandler...Dbutils 插入举例 Connection conn = null; try { QueryRunner runner = new QueryRunner...runner = new QueryRunner(); conn = JBBCUtils.getConnections3(); String sql =...runner = new QueryRunner(); conn = JBBCUtils.getConnections3(); String sql =...runner = new QueryRunner(); conn = JBBCUtils.getConnections3(); String sql =
queryRunner = MyDbUtils.getQueryRunner(); String sql = "select * from t_depart limit ?...queryRunner = MyDbUtils.getQueryRunner(); String sql = "insert into t_depart(name,notes)values...queryRunner = MyDbUtils.getQueryRunner(); String sql = "select * from t_depart where id = ?"...queryRunner = MyDbUtils.getQueryRunner(); String sql = "update t_depart set name = ?...queryRunner = MyDbUtils.getQueryRunner(); String sql = "delete from t_depart where id = ?"
QueryRunner类 该类简单化了SQL查询，它与ResultSetHandler组合在一起使用可以完成大部分的数据库操作，能够大大减少 编码量。...QueryRunner类提供了两个构造器： 默认的构造器 需要一个 javax.sql.DataSource 来作参数的构造器 QueryRunner类的主要方法： 更新 public int update...测试 // 测试添加 @Test public void testInsert() throws Exception { QueryRunner runner = new QueryRunner...runner = new QueryRunner(); Connection conn = JDBCUtils.getConnection3(); String sql = "delete from...runner = new QueryRunner(); Connection conn = JDBCUtils.getConnection3(); String sql = "select id
DBUtils封装了JDBC的操作，核心功能如下： 1、QueryRunner中提供对sql语句操作的API. 2、ResultSetHandler接口，用于定义select操作后，怎样封装结果集.... 3、DbUtils类是一个工具类，定义了关闭资源与事务处理的方法 QueryRunner核心类： update(Connection conn, String sql, Object...runner = new QueryRunner(); String sql = "UPDATE member SET leave_amount=100 WHERE id=2073699;";...runner = new QueryRunner(); String sql = "select * from member where id=2073699"; Connection...获取数据库连接 QueryRunner runner = new QueryRunner(); // 4.
对象 QueryRunner queryRunner = new QueryRunner(JdbcUtils.getDataSource()); String sql =...对象 QueryRunner queryRunner = new QueryRunner(JdbcUtils.getDataSource()); String sql =...对象 QueryRunner queryRunner = new QueryRunner(JdbcUtils.getDataSource()); String sql =...public void update() throws SQLException { //创建出QueryRunner对象 QueryRunner queryRunner...public void batch() throws SQLException { //创建出QueryRunner对象 QueryRunner queryRunner
刚才讲了使用QueryRunner插入、修改、更新数据，现在来学习一下使用QueryRunner进行数据库表查询。...queryRunner = new QueryRunner(dataSource); String sql = "select * from account"; //数组的每一个元素对应第一行数据的每一列...queryRunner = new QueryRunner(dataSource); String sql = "select * from account"; List...queryRunner = new QueryRunner(dataSource); String sql = "select * from account"; ListqueryRunner = new QueryRunner(dataSource); String sql = "select * from account"; Map<Object, Map
是dbutils中的一个方法，封装了jdbc的代码，在dao层使用简单框架 private QueryRunner runner; public QueryRunner getRunner...() { return runner; } public void setRunner(QueryRunner runner) { this.runner...-- 注入QueryRunner--> 没有QueryRunner...-- 配置QueryRunner 默认是单例对象 多个dao在使用同一个对象 可能用完它的时候一个在用另一个还没用完 导致线程互相干扰 多例的话会保证每次使用这个对象都是创建一个新的--...> QueryRunner" scope="prototype"> <!
QueryRunner有两种方式来管理连接，一种是在构建QueryRunner实例时通过构造方法传递一个数据源DataSource实例；另一种则是在调用相应的操作方法，如query、update、batch...; //创建QueryRunner实例 QueryRunner qr = new QueryRunner(DBCPUtil.getDataSource());...; //创建QueryRunner实例 QueryRunner qr = new QueryRunner(DBCPUtil.getDataSource());...; //创建QueryRunner实例 QueryRunner qr = new QueryRunner(DBCPUtil.getDataSource());...; //创建QueryRunner实例 QueryRunner qr = new QueryRunner(DBCPUtil.getDataSource());
删除数据 --> DBUtils @Test public void testUpdate() { QueryRunner queryRunner = new QueryRunner...queryRunner = new QueryRunner(); connection = JDBCTools.getConnection(); String sql...queryRunner = new QueryRunner(); try { List sh_dbs = (List) queryRunner.query...queryRunner = new QueryRunner(); String sql = "SELECT book_name bookName, isbn, price, stock...queryRunner = new QueryRunner(); String sql = "SELECT book_name bookName, isbn, price, stock
对象 QueryRunner queryRunner = new QueryRunner(JdbcUtils.getDataSource()); String sql =...queryRunner = new QueryRunner(JdbcUtils.getDataSource()); String sql = "SELECT * FROM student...queryRunner = new QueryRunner(JdbcUtils.getDataSource()); String sql = "DELETE FROM student...) throws SQLException { QueryRunner queryRunner = new QueryRunner(JdbcUtils.getDataSource());...public void batch() throws SQLException { //创建出QueryRunner对象 QueryRunner queryRunner
commons-dbutilsAPI介绍： org.apache.commons.dbutils.QueryRunner org.apache.commons.dbutils.ResultSetHandler...QueryRunner类提供了两个构造方法： 1、默认的构造方法 2、需要一个 javax.sql.DataSource 来作参数的构造方法。...QueryRunner类的主要方法 public Object query(Connection conn, String sql, Object[] params, ResultSetHandler...@Test public void dbUtilsQuery2() throws SQLException{ QueryRunner run = new QueryRunner(...为 增添加事务处理： @Test public void saveTx() throws SQLException{ QueryRunner run = new QueryRunner
类 顾名思义，QueryRunner中提供对sql语句操作的API....1.3 示例代码 能读懂这段代码即可 QueryRunner需要传入一个连接池对象，请通过学习JavaWeb基础 3.5节 数据库连接池进行配置 public class Demo { //...runner=new QueryRunner(C3P0Utils.getDataSource()); Object[] array=runner.query("select * from...runner=new QueryRunner(C3P0Utils.getDataSource()); List list=runner.query("select...runner=new QueryRunner(C3P0Utils.getDataSource()); List list=runner.query("select *
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