Jdbc.java工具类

package mes.util;

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

import org.springframework.stereotype.Service;
import org.springframework.web.context.ContextLoader;
import org.springframework.web.context.WebApplicationContext;

import com.mchange.v2.c3p0.ComboPooledDataSource;


@Service
public class JdbcUtil {
		
	private static ComboPooledDataSource dataSource;
	/* private static String driver = null;
    private static String url = null;
    private static String username = null;
    private static String password = null;*/
    static{
        try{
           /* //获取数据库连接驱动
            driver = Config.getString("database.driver");
            //获取数据库连接URL地址
            url = Config.getString("database.url");
            //获取数据库连接用户名
            username = Config.getString("database.username");
            //获取数据库连接密码
            password = Config.getString("database.password");
            
            //测试代码
            System.out.println("driver:"+driver);
            System.out.println("url:"+url);
            System.out.println("username:"+username);
            System.out.println("password:"+password);
            
            //加载数据库驱动
            Class.forName(driver);*/
        	//Connection connection = util.dataSource.getConnection();
        	System.out.println("static init");
        	WebApplicationContext appContext = ContextLoader.getCurrentWebApplicationContext();
        	//WebApplicationContextUtils.getRequiredWebApplicationContext(ServletContext sc); 
        	//ApplicationContext appContext=new ClassPathXmlApplicationContext("/config/applicationContext.xml");
        	 dataSource = (ComboPooledDataSource) appContext.getBean("dataSource");
        }catch (Exception e) {
            throw new ExceptionInInitializerError(e);
        }
    }
    
    /**
    * @Description: 获取数据库连接对象
    * @return Connection数据库连接对象
    * @throws SQLException
    */ 
   /* public static Connection getConnection() throws SQLException{
        return DriverManager.getConnection(url, username,password);
    }*/
    
    public static Connection getConnection(){  
        try {  
        	Connection connection = dataSource.getConnection();
            return connection;  
        } catch (SQLException e) {  
            e.printStackTrace();  
            return null;  
        } 
    }  
    
    /**
    * @Method: release
    * @Description: 释放资源，
    *     要释放的资源包括Connection数据库连接对象，负责执行SQL命令的Statement对象，存储查询结果的ResultSet对象
    * @param conn
    * @param st
    * @param rs
    */ 
    public static void release(Connection conn,Statement st,ResultSet rs){
        if(rs!=null){
            try{
                //关闭存储查询结果的ResultSet对象
                rs.close();
            }catch (Exception e) {
                e.printStackTrace();
            }
            rs = null;
        }
        if(st!=null){
            try{
                //关闭负责执行SQL命令的Statement对象
                st.close();
            }catch (Exception e) {
                e.printStackTrace();
            }
        }
        
        if(conn!=null){
            try{
                //关闭Connection数据库连接对象
                conn.close();
            }catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
}