JavaUtils的内容

package com.eden.utils;

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

import javax.ejb.Local;
import javax.sql.DataSource;

import com.mchange.v2.c3p0.ComboPooledDataSource;

public class JdbcUtils {
    private static ThreadLocal<Connection> local = new ThreadLocal<Connection>();
    private static ComboPooledDataSource dataSource;
    static{
        try {
            dataSource = new ComboPooledDataSource("day13");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    public static DataSource getDataSource(){
        return dataSource;
    }
    public static Connection getConnection() throws SQLException{
        Connection conn = local.get();
        if(conn == null){
            conn = dataSource.getConnection();
            local.set(conn);
        }
        return conn;
    }
    
    
    public static void closeResource(Connection conn, Statement st, ResultSet rs){
            try {
                if(rs != null){
                    rs.close();
                }
            } catch (SQLException e) {
                e.printStackTrace();
            }finally{
                try {
                    if(st != null){
                        st.close();
                    }
                } catch (SQLException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }finally{
                    try {
                        if(conn != null){
                            conn.close();
                        }
                    } catch (SQLException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                }
            }
    }
    public static void commitAndClose(Connection conn){
        try {
            if(conn != null){
                conn.commit();
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }finally{
            JdbcUtils.closeResource(conn, null, null);
        }
    }
    public static void rollbackAndClose(Connection conn){
        try {
            if(conn != null){
                conn.rollback();
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }finally{
            JdbcUtils.closeResource(conn, null, null);
        }
    }
}