1）准备
a》jdbc驱动包
2）原理：
编写jdbc数据库连接，命令行传递参数，最后打成jar包
3）实施
public static void main(String[] args) { // 输入参数判断 // 1）DB_URL // 2）Username // 3）Password 4）Sql-执行Sql if (args == null || args.length < 4) { System.out.println("传递的参数不足4个【url,Username,Password,Sql(含空格用双引号引起)】,参数之间用空格分开。"); return; } // 获取参数 String url = args[0]; String user = args[1]; String password = args[2]; String sql = args[3]; // 设置驱动名称 String driverName = "oracle.jdbc.driver.OracleDriver"; if (url.contains("jdbc:mysql")) { driverName = "com.mysql.jdbc.Driver"; } // 加载驱动,建立连接 Connection con = null; Statement statement = null; ResultSet resultSet = null; try { Class.forName(driverName); con = DriverManager.getConnection(url, user, password); System.out.println("db连接成功."); statement = con.createStatement(); resultSet = statement.executeQuery(sql); ResultSetMetaData resultMetaData = resultSet.getMetaData(); // 获取所有列名 int cols = resultMetaData.getColumnCount(); String resultRow = ""; for (int i = 1; i <= cols; i++) { resultRow += resultMetaData.getColumnName(i) + " "; } System.out.println("数据结果："); System.out.println(resultRow); // 获取所有值 while (resultSet.next()) { resultRow = ""; for (int i = 1; i <= cols; i++) { try { resultRow += resultSet.getString(i) + " "; } catch (NullPointerException e) { e.printStackTrace(); } } System.out.println(resultRow); } } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (SQLException e) { e.printStackTrace(); } finally { try { resultSet.close(); } catch (SQLException e) { e.printStackTrace(); }finally{ try { statement.close(); con.close(); System.out.println("db连接关闭成功."); } catch (SQLException e) { e.printStackTrace(); } } } }