brenda写的sql增删改查模板代码

package com.cpcnet.db;import java.sql.Connection;import java.sql.DriverManager;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.SQLException;import java.sql.Statement;import java.util.Properties;import com.cpcnet.utils.ExceptionHelper;import com.cpcnet.utils.PropertiesHelper;public class MysqlDBConn {public static String DB_CONFIG = "com/cpcnet/config/db.properties";private Connection conn = null;private Statement stmt = null;private ResultSet rs = null;private String MY_DRIVER = ""; private String MY_URL = ""; private String MY_USERNAME = ""; private String MY_PASSWORD = "";public MysqlDBConn() {init("mysql");}public MysqlDBConn(String prefixName) {init(prefixName);}public int execUpdate(String sql) {int flag = 0;try {stmt = this.getConn().createStatement();flag = stmt.executeUpdate(sql);} catch (SQLException e) {e.printStackTrace();ExceptionHelper.getInstance().addExceptionList(e);}return flag;}public int execUpdate(String sql, Object[] parameters) {int flag = 0;try {PreparedStatement pstmt = this.getConn().prepareStatement(sql);for(int i=0, l=parameters.length; i<l; i++) {pstmt.setObject(i+1, parameters[i]);}flag = pstmt.executeUpdate();} catch (SQLException e) {e.printStackTrace();ExceptionHelper.getInstance().addExceptionList(e);}return flag;}public ResultSet execQuery(String sql, Object[] parameters) {try {PreparedStatement pstmt = this.getConn().prepareStatement(sql);for(int i=0, l=parameters.length; i<l; i++) {pstmt.setObject(i+1, parameters[i]);}rs = pstmt.executeQuery();} catch (SQLException e) {e.printStackTrace();ExceptionHelper.getInstance().addExceptionList(e);}return rs;}public ResultSet execQuery(String sql) {try {stmt = this.getConn().createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_READ_ONLY);rs = stmt.executeQuery(sql);} catch (SQLException e) {e.printStackTrace();ExceptionHelper.getInstance().addExceptionList(e);}return rs;}private void init(String prefixName) {Properties prop = new PropertiesHelper().getProperty(DB_CONFIG);MY_DRIVER = prop.getProperty(prefixName + "_driver");MY_URL = prop.getProperty(prefixName + "_url");MY_USERNAME = prop.getProperty(prefixName + "_username");MY_PASSWORD = prop.getProperty(prefixName + "_password");}public void closeDB(){try {if(rs != null) {rs.close();}if(stmt != null) {stmt.close();}if(conn != null) {conn.close();}} catch (SQLException e) {e.printStackTrace();ExceptionHelper.getInstance().addExceptionList(e);}}public Connection getConn(){try {if(conn == null) {Class.forName(MY_DRIVER).newInstance();conn = DriverManager.getConnection(MY_URL, MY_USERNAME, MY_PASSWORD);}return conn;} catch (Exception e) {e.printStackTrace();ExceptionHelper.getInstance().addExceptionList(e);}return conn;}}