sqloperatedemo.java

Java程序设计实用案例教程源代码

package database;

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

public class SQLOperateDemo {

	public static void main(String[] args) {
		Scanner cin = new Scanner(System.in);
		try {
			String driverName = null;
			driverName = "org.gjt.mm.mysql.Driver";
			Class.forName(driverName);
			DriverManager.registerDriver(new org.gjt.mm.mysql.Driver());
		} catch (ClassNotFoundException e1) {
		} catch (SQLException se) {
			System.out.println(" " + se.getMessage());
		}
		System.out.println("flag1");
		String url = "jdbc:mysql://localhost:3306/test";
		String user = "root";
		String pwd = "";
		Connection conn = null;
		try {
			conn = DriverManager.getConnection(url, user, pwd);
		} catch (Exception ex) {
			ex.printStackTrace();
		}
		System.out.println("实例8.2 使用接口执行SQL语句" + 
				"所使用的数据库为test，所查询的表为userinfo.");
		System.out.println("请选择\n1：不带参数的SQL语句\n"
				+ "2：带参数的SQL语句");
		int flag = 0;
		flag = cin.nextInt();
		if (flag == 1) {
			try {
				Statement stmt = conn.createStatement();
				String sql = "select * from userinfo";
				ResultSet rs = stmt.executeQuery(sql);
				while (rs.next()) {
					String username = rs.getString("username");
					int age = rs.getInt("age");
					String password = rs.getString("password");
					System.out.println("username : " + username + " age : "
							+ age + " password :" + password);
				}
				rs.close();
				stmt.close();
				conn.close();
			} catch (SQLException se) {
				se.printStackTrace();
			}
		} else {
			try {
				Statement stmt = conn.createStatement();
				String sql = "select * from userinfo";
				ResultSet rs = stmt.executeQuery(sql);
				while (rs.next()) {
					String username = rs.getString("username");
					int age = rs.getInt("age");
					String password = rs.getString("password");
					System.out.println("username : " + username + " age : "
							+ age + " password :" + password);
				}
				rs.close();
				stmt.close();
				conn.close();
			} catch (SQLException se) {
				se.printStackTrace();
			}

		}
	}
}