java操作数据库的类——SqlHelper（读取properties配置文件）

dbUserName=root
dbPassword=root
dbDriver=com.mysql.jdbc.Driver
dbUrl=jdbc\:mysql\://127.0.0.1\:3306/test?useUnicode\=true&characterEncoding\=utf8

package com.hsp.utils;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;
import java.sql.*;
public class SqlHelper
{
//定义变量
private static Connection ct = null;
//大多数情况下用preparedstatement替代statement
private static PreparedStatement ps = null;
private static ResultSet rs = null;

//连接数据库的参数
private static String url = "";
private static String username = "";
private static String driver = "";
private static String passwd = "";

private static CallableStatement cs = null;
public static CallableStatement getCs()
{
return cs;
}
private static Properties  pp = null;
private static InputStream fis = null;
//加载驱动，只需要一次，用静态代码块
static
{
try
{
//从dbinfo.properties
pp = new Properties();
fis=SqlHelper.class.getClassLoader().getResourceAsStream("mysql.properties");
//fis = new FileInputStream();
pp.load(fis);
url = pp.getProperty("dbUrl");
driver = pp.getProperty("dbDriver");
username = pp.getProperty("dbUserName");
passwd = pp.getProperty("dbPassword");

Class.forName(driver);
}
catch (Exception e)
{
e.printStackTrace();
}
finally
{
try
{ fis.close();}
catch(IOException e) {e.printStackTrace();}
fis = null;//垃圾回收站上收拾
}

}
//得到连接
public static Connection getConnection()
{
try
{ct = DriverManager.getConnection(url,username,passwd);}
catch(Exception e) {e.printStackTrace();}
return ct;
}

//*************callPro1存储过程函数1*************
public static CallableStatement callPro1(String sql,String[] parameters)
{
try{
ct = getConnection();
cs = ct.prepareCall(sql);
if(parameters!=null){
for(int i=0;i<parameters.length;i++){
cs.setObject(i+1,parameters[i]);
}
}
cs.execute();
}
catch(Exception e) { e.printStackTrace(); throw new RuntimeException(e.getMessage());}
finally
{ close(rs,cs,ct);}
return cs;
}

//*******************callpro2存储过程2************************
public static CallableStatement callPro2(String sql,String[] inparameters,
Integer[] outparameters)
{
try
{
ct = getConnection();
cs = ct.prepareCall(sql);
if(inparameters!=null)
{
for(int i=0;i<inparameters.length;i++)
{
cs.setObject(i+1,inparameters[i]);
}
}
//cs.registerOutparameter(2,oracle.jdbc.OracleTypes.CURSOR);
if(outparameters!=null)
{
for(int i=0;i<outparameters.length;i++)
{
cs.registerOutParameter(inparameters.length+1+i,outparameters[i]);
}
}
cs.execute();
}
catch(Exception e) {
e.printStackTrace(); throw new RuntimeException(e.getMessage());
}
finally
{

}
return cs;
}
public static ResultSet executeQuery(String sql,String[] parameters)
{
try
{
ct=getConnection();
ps=ct.prepareStatement(sql);
if(parameters!=null)
{
for(int i=0;i<parameters.length;i++)
{
ps.setString(i+1,parameters[i]);
}
}
rs = ps.executeQuery();
}
catch(Exception e)
{
e.printStackTrace();
throw new RuntimeException(e.getMessage());
}
finally
{

}
return rs;
}

public static Connection getCt()
{
return ct;
}
public static PreparedStatement getPs()
{
return ps;
}
public static ResultSet getRs()
{
return rs;
}

public static void executeUpdate2(String[] sql,String[][] parameters)
{
try
{
ct = getConnection();
ct.setAutoCommit(false);

for(int i=0;i<sql.length;i++)
{

if(null!=parameters[i])
{
ps = ct.prepareStatement(sql[i]);
for(int j=0;j<parameters[i].length;j++)
{
ps.setString(j+1,parameters[i][j]);
}
ps.executeUpdate();
}

}

ct.commit();

}catch (Exception e)
{
e.printStackTrace();
try
{
ct.rollback();
}
catch (SQLException e1)
{
e1.printStackTrace();
}
throw  new RuntimeException(e.getMessage());
}finally
{
close(rs,ps,ct);
}

}

//先写一个update、delete、insert
//sql格式：update 表名 set 字段名 =？where 字段=？
//parameter神应该是（”abc“,23）
public static void executeUpdate(String sql,String[] parameters)
{
try
{
ct=getConnection();
ps = ct.prepareStatement(sql);
if(parameters!=null)
{
for(int i=0;i<parameters.length;i++)
{
ps.setString(i+1,parameters[i]);
}

}
ps.executeUpdate();
}
catch(Exception e)
{
e.printStackTrace();//开发阶段
//抛出异常
//可以处理，也可以不处理
throw new RuntimeException(e.getMessage());
}
finally
{
close(rs,ps,ct);
}
}

public static void close(ResultSet rs,Statement ps,Connection ct)
{
//关闭资源(先开后关)
if(rs!=null)
{
try
{
rs.close();
}
catch(SQLException e)
{
e.printStackTrace();
}
rs=null;
}
if(ps!=null)
{
try
{
ps.close();
}
catch(SQLException e)
{
e.printStackTrace();
}
ps=null;
}
if(null!=ct)
{
try
{
ct.close();
}
catch(SQLException e)
{
e.printStackTrace();
}
ct=null;
}
}
}