Java每日一题24（最后一题）

昨天又写了个双色球程序，作为Java每日一题系列的终止符：
Java链接derby数据库，我将2003年至今的数据导入到了数据库中，可以对数据进行CRUD，最大的好处是，比如输入03 05 07，可以查到2003年至今这三个号分别在哪期出现过。
但是我觉得自己写的太拖沓，大家看看有哪些地方可以重构下，呵呵

我把项目打成jar包作为附件了，不过很奇怪，打成包以后，就找不到jdbc驱动了，了解这个和问题的朋友麻烦告知，万分感谢！！！


liangwenzheng 写道
敬请博主放过JAVA初级程序员！别再出这些题目了，会把人引入歧途的~结果只有一个，造就一批适用JAVA程序设计语言写C程序的人！
我好心劝你一句而已，你却和我抬杠，呵呵~
初学者走的路很重要，要是一开始就被带沟里去了，后患无穷。
本着 对他人做点善事的思想 再次拜请博主三思~
PS:别拿无知当个性！


为了不把一些高手带到沟里去，我决定停止出题，感谢大家多日以来的关注和支持，在此谢过，我会继续写其他方面的blog，Java，Python，Oracle，DB2，Linux，AIX，欢迎大家MSN交流：[e-mail]

import java.io.File;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import java.text.DecimalFormat;
import java.text.NumberFormat;
import java.util.Properties;
import java.util.Scanner;

public class DoubleBall {
	
	private String driver = "org.apache.derby.jdbc.EmbeddedDriver";
	private String dbName = "/DoubleBall";
	private String dbURL = "jdbc:derby:" + dbName;

	private Connection conn = null;
	private Statement st = null;
	private ResultSet rs = null;

	public static void main(String[] args) {
		Properties props = System.getProperties();
		String extdir = props.getProperty("java.ext.dirs");
		extdir = extdir + File.pathSeparator + "lib\\derby.jar";
		
		while (true) {
			System.out.println("What do you want to do?");
			System.out.println("1.Create Data");
			System.out.println("2.Delete Data");
			System.out.println("3.Update Data");
			System.out.println("4.Retrieve Data");
			System.out.println("5.Display All Data");
			System.out.println("6.Exit");
			Scanner scanner = new Scanner(System.in);
			int selected = scanner.nextInt();

			DoubleBall doubleBall = new DoubleBall();
			if (selected == 1) {
				doubleBall.CreateData();
			} else if (selected == 2) {
				doubleBall.DeleteData();
			} else if (selected == 3) {
				doubleBall.UpdateData();
			} else if (selected == 4) {
				doubleBall.RetriveData();
			} else if (selected == 5) {
				doubleBall.DisplayAll();
			} else {
				System.exit(selected);
			}
		}
	}

	private void getConn() throws Exception {
		Class.forName(driver);
		conn = DriverManager.getConnection(dbURL);
		st = conn.createStatement();
	}

	private void closeConn() throws Exception {
		if (rs != null) {
			rs.close();
		}
		st.close();
		conn.close();
	}

	public void DisplayAll() {
		try {
			getConn();
			rs = st.executeQuery("select * from DATA");
			DecimalFormat df = (DecimalFormat) NumberFormat.getInstance();
			df.applyPattern("00");
			while (rs.next()) {
				int id = rs.getInt(1);
				int red_1 = rs.getInt(2);
				int red_2 = rs.getInt(3);
				int red_3 = rs.getInt(4);
				int red_4 = rs.getInt(5);
				int red_5 = rs.getInt(6);
				int red_6 = rs.getInt(7);
				int blue = rs.getInt(8);

				System.out.println(id + " " + df.format(red_1) + " "
						+ df.format(red_2) + " " + df.format(red_3) + " "
						+ df.format(red_4) + " " + df.format(red_5) + " "
						+ df.format(red_6) + " " + df.format(blue));

			}
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			try {
				closeConn();
			} catch (Exception e) {
				e.printStackTrace();
			}
		}
	}

	public void CreateData() {
		System.out
				.println("Please input the data like this:2009024 01 03 17 23 30 33 12");
		Scanner scanner = new Scanner(System.in);
		String[] temp = scanner.nextLine().split(" ");

		try {
			getConn();
			st.executeUpdate("insert into DATA values(" + temp[0] + ","
					+ temp[1] + "," + temp[2] + "," + temp[3] + "," + temp[4]
					+ "," + temp[5] + "," + temp[6] + "," + temp[7] + ")");
			System.out.println("Input Successful!");
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			try {
				closeConn();
			} catch (Exception e) {
				e.printStackTrace();
			}
		}
	}

	public void RetriveData() {
		System.out.println("Please input the number,like this:05 07");
		Scanner scanner = new Scanner(System.in);
		String[] temp = scanner.nextLine().split(" ");
		try {
			getConn();
			rs = st.executeQuery("select * from DATA");
			DecimalFormat df = (DecimalFormat) NumberFormat.getInstance();
			df.applyPattern("00");
			int count = 0;
			System.out.println("======================================");
			while (rs.next()) {
				int[] balls = new int[7];
				int id = rs.getInt(1);
				for (int i = 0; i < 7; i++) {
					balls[i] = rs.getInt(i + 2);
				}

				String data = df.format(balls[0]) + " " + df.format(balls[1])
						+ " " + df.format(balls[2]) + " " + df.format(balls[3])
						+ " " + df.format(balls[4]) + " " + df.format(balls[5]);

				String regex = "";
				for (String s : temp) {
					regex = regex + ".*" + s;
				}
				regex = regex + ".*";

				if (data.matches(regex)) {
					count++;
					System.out.println(id + " " + df.format(balls[0]) + " "
							+ df.format(balls[1]) + " " + df.format(balls[2])
							+ " " + df.format(balls[3]) + " "
							+ df.format(balls[4]) + " " + df.format(balls[5])
							+ " " + df.format(balls[6]));
				}
			}
			System.out.println("======================================");
			System.out.println("From 20030101 to now: It comes " + count+" times!");
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			try {
				closeConn();
			} catch (Exception e) {
				e.printStackTrace();
			}
		}
	}

	public void UpdateData() {
		System.out
				.println("Please input the data ID which you want to update,like this:2009024 01 03 17 23 30 33 12");
		Scanner scanner = new Scanner(System.in);
		String[] temp = scanner.nextLine().split(" ");

		try {
			getConn();
			st.executeUpdate("update DATA set RED_1=" + temp[1] + ",RED_2="
					+ temp[2] + ",RED_3=" + temp[3] + ",RED_4=" + temp[4]
					+ ",RED_5=" + temp[5] + ",RED_6=" + temp[6] + ",BLUE="
					+ temp[7] + " where ID=" + temp[0]);
			System.out.println("Update Successful!");
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			try {
				closeConn();
			} catch (Exception e) {
				e.printStackTrace();
			}
		}
	}

	public void DeleteData() {
		System.out
				.println("Please input the data ID which you want to detete,like this:2009024");
		Scanner scanner = new Scanner(System.in);
		String temp = scanner.nextLine();
		try {
			getConn();
			st.executeUpdate("delete from DATA where ID=" + temp);
			System.out.println("Delete Successful!");
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			try {
				closeConn();
			} catch (Exception e) {
				e.printStackTrace();
			}
		}
	}
}

评论

5 楼 Chameleon 2009-03-10  

重在算法，不在API啦。如果用会几个API来评价高手的话，那大家都去背API文档好了。

4 楼 jythoner 2009-03-10  

aben6448 写道

一段时间不能上网，回来竟发现每日一题不再每日了。。。加油，期待更好的东西出来~~~

有空msn聊，呵呵

3 楼 aben6448 2009-03-10  

一段时间不能上网，回来竟发现每日一题不再每日了。。。
加油，期待更好的东西出来~~~

2 楼 jythoner 2009-03-10  

SoftGiant 写道

楼主冲动了，要淡定 
楼主的初衷是高尚的，这些题目虽然简单了点，但是对于初学者的编程思路养成还是有一定帮助的，有基础的做做也挺好的，围棋职业高手每天还都要做一些死活题练手呢。

呵呵，多谢支持，我再换换思路，弄些更有意思的东西出来搞。
每日一题系列虽然总结了，但blog仍在，思想仍在，哈哈

1 楼 SoftGiant 2009-03-10  

楼主冲动了，要淡定 
楼主的初衷是高尚的，这些题目虽然简单了点，但是对于初学者的编程思路养成还是有一定帮助的，有基础的做做也挺好的，围棋职业高手每天还都要做一些死活题练手呢。