Java_JDBC

/**
 * 建链接池
 */

public class DB_Pools {

	private final static String user = "数据库账号";
	private final static String password = "数据库密码";
	private final static String url = "jdbc:mysql://localhost:3306/数据库名";
	private final static String driverClass = "com.mysql.jdbc.Driver";
	private static LinkedList<Connection> pools = new LinkedList<Connection>();
	private static Connection con = null;

	/**
	 * 注册驱动
	 */
	static {
		try {
			System.out.println("---Load static---");
			Class.forName(driverClass);
			createPools(5, pools);
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
		}
	}

	/**
	 * 获得Pools
	 * 
	 * @return Pools
	 */
	public static LinkedList<Connection> getPools() {
		return pools;
	}

	/**
	 * 显示Pools
	 * 
	 * @param pools
	 */
	public static void setPools(LinkedList<Connection> pools) {
		DB_Pools.pools = pools;
	}

	/**
	 * 创建数据库一个连接
	 * 
	 * @return con
	 */
	public static Connection poolsConnection() {
		try {
			con = DriverManager.getConnection(url, user, password);
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return con;
	}

	/**
	 * 创建数据库number个连接,把连接存放在LinkedList<Connection>数组中的一个方法
	 * 
	 * @param number
	 *            数
	 * @param linkedList
	 *            链表
	 */
	public static void createPools(int number, LinkedList<Connection> linkedList) {
		for (int i = 0; i < number; i++) {
			con = poolsConnection();
			linkedList.addLast(con);
		}
	}

	/**
	 * 从连接池中取出最前面的数据库连接
	 * 
	 * @return con
	 */
	public static Connection getSingleConnection() {
		con = pools.removeFirst();
		return con;
	}

	/**
	 * 把使用结束后的数据库连接放回连接池的末尾
	 * 
	 * @param con
	 */
	public static void freeConnection(Connection con) {
		pools.addLast(con);
	}
}

/**
 * 关闭资源
 */
public class DB extends DB_Pools {

	private static Connection con = null;

	/**
	 * 获取连接
	 * 
	 * @return con
	 */
	public static Connection getConnection() {
		con = getSingleConnection();
		return con;
	}
	
	/**
	 * 关闭资源
	 * @param con
	 * @param pst
	 * @param rst
	 */
	public static void close(Connection con, Statement pst, ResultSet rst) {

		try {
			if (rst != null) {
				rst.close();
				rst = null;
			}
		} catch (SQLException e) {
			e.printStackTrace();

		} finally {
			try {
				if (pst != null) {
					pst.close();
					pst = null;
				}

			} catch (SQLException e) {
				e.printStackTrace();
			} finally {
				if (con != null) {
					freeConnection(con);
				}
			}
		}
	}
}

/**
 * 继承该Class调用Methods
 */
public class DB_Utils extends DB {

	private static Connection con = null;
	private static PreparedStatement pst = null;
	private static ResultSet rst = null;

	/**
	 * 数据库的操作，添加 修改 删除
	 * 
	 * @param sql
	 *            插入SQL语句
	 * @param objects
	 *            插入对象
	 * @return b (true / false)
	 */
	public static boolean Operation_Create_Update_Delete(String sql,
			Object[] objects) {
		boolean b = false;
		con = getConnection();
		try {
			pst = con.prepareStatement(sql);
			if (objects != null) {
				for (int i = 0; i < objects.length; i++) {
					pst.setObject(i + 1, objects[i]);
				}
			}
			int j = pst.executeUpdate();
			if (j > 0) {
				b = true;
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return b;
	}

           /**
	 * 数据的插入
	 * 
	 * @param sql
	 *            插入SQL语句
	 * @param objects
	 *            插入对象
	 * @return id 返回Id 
	 */

	public static int Operation_Create(String sql, Object[] objects) {
		int id = 0;
		con = getConnection();
		try {
			pst = con.prepareStatement(sql, Statement.RETURN_GENERATED_KEYS);
			if (objects != null) {
				for (int i = 0; i < objects.length; i++) {
					pst.setObject(i, objects[i]);
				}
			}
			int j = pst.executeUpdate();
			if (j > 0) {
				rst = pst.getGeneratedKeys();
				if (rst.next()) {
					id = rst.getInt(1);
				}
			}
		} catch (SQLException e) {
			e.printStackTrace();
		} finally {
			close(con, pst, rst);
		}
		return id;
	}

	/**
	 * 查询需要的信息获得需要的信息
	 * 
	 * @param sql
	 *            插入SQL语句
	 * @param objects
	 *            插入对象
	 * @return rst 结果
	 */
	public static ResultSet Operation_Search(String sql, Object[] objects) {
		con = getConnection();
		try {
			pst = con.prepareStatement(sql);
			if (objects != null) {
				for (int i = 0; i < objects.length; i++) {
					pst.setObject(i + 1, objects[i]);
				}
			}
			rst = pst.executeQuery();
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return rst;
	}

	public static void close(ResultSet rst) {
		close(con, pst, rst);
	}
}