JDBC公共操作類

    import java.sql.Connection;

    import java.sql.DriverManager;

    import java.sql.ResultSet;

    import java.sql.SQLException;

    import java.sql.Statement;


public class DBUtil {  
    public static final String DRIVER = "com.mysql.jdbc.Driver";  
    public static final String URL = "jdbc:mysql://localhost:3306/db";  
    public static final String USERNAME = "root";  
    public static final String PASSWORD = "root";  

    /** 
     * 通過靜態代碼塊 注冊數據庫驅動 
     */  
    static {  
        try {  
            Class.forName(DRIVER);  
        } catch (ClassNotFoundException e) {  
            e.printStackTrace();  
        }  
    }  

    /** 
     * 獲得Connection 
     *  
     * @return 
     */  
    public static Connection getConnection() {  
        Connection conn = null;  
        try {  
            conn = DriverManager.getConnection(URL, USERNAME, PASSWORD);  
        } catch (SQLException e) {  
            e.printStackTrace();  
        }  
        return conn;  
    }  

    /** 
     * 獲得Statement 
     *  
     * @return 
     */  
    public static Statement getStatement() {  
        Statement st = null;  
        try {  
            st = getConnection().createStatement();  
        } catch (SQLException e) {  
            e.printStackTrace();  
        }  
        return st;  
    }  

    /** 
     * 關閉ResultSet 
     *  
     * @param rs 
     */  
    public static void closeResultSet(ResultSet rs) {  
        if (rs != null) {  
            try {  
                rs.close();  
            } catch (SQLException e) {  
                e.printStackTrace();  
            }  
        }  
    }  

    /** 
     * 關閉Statement 
     *  
     * @param st 
     */  
    public static void closeStatement(Statement st) {  
        if (st != null) {  
            try {  
                st.close();  
            } catch (SQLException e) {  
                e.printStackTrace();  
            }  
        }  
    }  

    /** 
     * 關閉Connection 
     *  
     * @param conn 
     */  
    public static void closeConnection(Connection conn) {  
        if (conn != null) {  
            try {  
                conn.close();  
            } catch (SQLException e) {  
                e.printStackTrace();  
            }  
        }  
    }  

    /** 
     * 關閉全部 
     *  
     * @param rs 
     * @param sta 
     * @param conn 
     */  
    public static void closeAll(ResultSet rs, Statement sta, Connection conn) {  
        closeResultSet(rs);  
        closeStatement(sta);  
        closeConnection(conn);  
    }  

}  </pre>