Eclipse/Idea
maven管理，SSM框架
给予一些特殊的需求原因，我们可能会直接通过sql来操作数据库，这里提供了一个工具类DBHelper.java来实现基本的增删改查package com.yj.utils.dbHelper;import com.yj.utils.properties.PathUtil;import com.yj.utils.properties.PropertiesUtil;import javax.servlet.jsp.jstl.sql.Result;import javax.servlet.jsp.jstl.sql.ResultSupport;import java.sql.*;import java.util.List;import java.util.logging.Level;import java.util.logging.Logger;public class DBHelper {private String sql; //要传入的sql语句public void setSql(String sql) {this.sql = sql;}private List sqlValues; //sql语句的参数public void setSqlValues(List sqlValues) {this.sqlValues = sqlValues;}private List sqlValue; //sql语句的参数public void setSqlValue(List
sqlValues) {this.sqlValue = sqlValues;}public Connection con; //连接对象/*public void setCon(Connection con) {this.con = con;}*/public DBHelper(){this.con=getConnection(); //给Connection的对象赋初值}/*** 获取数据库连接* @return*/private Connection getConnection(){String driver_class=null;String driver_url=null;String database_user=null;String database_password=null;try {PropertiesUtil propertiesUtil = new PropertiesUtil(PathUtil.getClassPath() + '/config/jdbc.properties');driver_class='com.mysql.jdbc.Driver'; //获取数据库配置文件driver_url='jdbc:mysql://127.0.0.1:3306/lsd_wx_navigation';database_user=propertiesUtil.getString('jdbc_username');database_password=propertiesUtil.getString('jdbc_password');Class.forName(driver_class);con=DriverManager.getConnection(driver_url,database_user,database_password);} catch (ClassNotFoundException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}return con;}/*** 关闭数据库* @param con* @param pst* @param rst*/private void closeAll(Connection con,PreparedStatement pst,ResultSet rst){if(rst!=null){try {rst.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}}if(pst!=null){try {pst.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}}if(con!=null){try {con.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}}}/*** 关闭数据库* @param con* @param pst* @param rst*/private void closeAll(Connection con,Statement pst,ResultSet rst){if(rst!=null){try {rst.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}}if(pst!=null){try {pst.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}}if(con!=null){try {con.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}}}/*** 查找* @param* @param* @return*/public Result executeQuery(){Result result=null;ResultSet rst=null;PreparedStatement pst=null;try {pst=con.prepareStatement(sql);if(sqlValues!=null&&sqlValues.size()>0){ //当sql语句中存在占位符时setSqlValues(pst,sqlValues);}rst=pst.executeQuery();result= ResultSupport.toResult(rst); //一定要在关闭数据库之前完成转换} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}finally{this.closeAll(con, pst, rst);}return result;}/*** 增删改* @return*/public int executeUpdate(){int result=-1;PreparedStatement pst=null;try {pst=con.prepareStatement(sql);if(sqlValues!=null&&sqlValues.size()>0){ //当sql语句中存在占位符时setSqlValues(pst,sqlValues);}result=pst.executeUpdate();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}finally{this.closeAll(con, pst, null);}return result;}/*** 使用PreparedStatement加批量的方法* @return*/public int[] executeUpdateMore(){int[] result=null;try{PreparedStatement prest =con.prepareStatement(sql,ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_READ_ONLY);for(List sqlValueString : sqlValue){for(int i=0;i
这里进行junit测试@Testpublic void query(){//这里需要注意的是：不能直接调用dbHelper.executeQuery()等方法，因为在executeQuery()中的finally中已经将连接关闭，我们将取不到set中的值DBHelper dbHelper = new DBHelper();String sql = 'select * from message_record';ResultSet resultSet = null;List sqlValues = new ArrayList<>();sqlValues.add(list);sqlValues.add(list1);dbHelper.setSql(sql);dbHelper.setSqlValue(sqlValues);int[] ints = dbHelper.executeUpdateMore();System.out.println('ints===' + ints);int flag = 0;if (null != ints && 0 < ints.length) {for (int anInt : ints) {flag+=anInt;}}System.out.println('flag================' + flag);}