connectionmanager.java

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package com.restrant.dao;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import com.restrant.util.*;

public class ConnectionManager {
	public static synchronized Connection getConnection() {
	    String driverClass = Env.getInstance().getProperty("driver");
	    String url = Env.getInstance().getProperty("url");
//	    String user = Env.getInstance().getProperty("user");
//	    String password = Env.getInstance().getProperty("password");
	    Connection con = null;
	    try{
	    	Class.forName(driverClass);
	    	con = DriverManager.getConnection(url,"sa","sa");
	    }
	    catch(Exception e){
	    	e.printStackTrace();
	    	//throw new DBAccessException("不能取得数据库连接！");
	    }
	    return con;
	}
	
	/**
	 * 关闭连接
	 * 
	 * @param dbConnection
	 *            Connection
	 */
	public static void closeConnection(Connection dbConnection) {
		try {
			if (dbConnection != null && (!dbConnection.isClosed())) {
				dbConnection.close();
			}
		} catch (SQLException sqlEx) {
			sqlEx.printStackTrace();
		}

	}

	/**
	 * 关闭结果集
	 * 
	 * @param res
	 *            ResultSet
	 */
	public static void closeResultSet(ResultSet res) {
		try {
			if (res != null) {
				res.close();
				res = null;
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}

	/**
	 * 关闭语句
	 * 
	 * @param pStatement
	 *            PreparedStatement
	 */

	public static void closeStatement(PreparedStatement pStatement) {
		try {
			if (pStatement != null) {
				pStatement.close();
				pStatement = null;
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}
	
	public static void main(String[] args) {
		Connection connection = ConnectionManager.getConnection();
		System.out.println(connection);
	}

}