pageclient.java

加拿大达内科技有限公司配需java程序员的上课时的代码

package day03;

import java.io.*;
import java.sql.*;

public class PageClient {
	private int pageSize;
	private int currentPage = 1;
	private PageTool tool = new PageTool();
	private String[] UI = { "开始程序(i) 退出(其他任意键)", "请出入页面长度:",
			"上一页(u) 下一页(d) 指定页(p)　返回(b)", "请输入页码:	 " };

	public String prompt(String message) {
		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		String command = "";
		System.out.println(message);
		int num = 1;
		try {
			while ("".equals((command = in.readLine()).trim())) {
				System.out.println(++num + "->");
			}
		} catch (IOException e) {
			e.printStackTrace();
		}
		return command;
	}

	public static void main(String[] args) {
		PageClient c = new PageClient();
		while (c.runOrNot()) {
			while (c.readOrNot()) {
			}
		}
	}

	private boolean readOrNot() {
		String command = prompt(UI[2]);
		if ("u".equals(command)) {
			if (currentPage > 1) {
				System.out.print(tool.getPage(--currentPage));
			}
		} else if ("d".equals(command)) {
			if (currentPage < tool.countPageNum()) {
				System.out.print(tool.getPage(++currentPage));
			}
		} else if ("p".equals(command)) {
			String pn = prompt(UI[3] + "(总页数" + tool.countPageNum() + "页");
			currentPage = Integer.parseInt(pn);
			if (currentPage > 0 && currentPage <= tool.countPageNum()) {
				System.out.print(tool.getPage(currentPage));
			}
		} else if ("b".equals(command)) {
			return false;
		}
		return true;
	}

	private boolean runOrNot() {
		String command = prompt(UI[0]);
		if ("i".equals(command)) {
			command = prompt(UI[1]);
			try {
				pageSize = Integer.parseInt(command);
				System.out.println(pageSize);
				tool.setPageSize(pageSize);
			} catch (Exception e) {
				e.printStackTrace();
			}
		} else {
			return false;
		}
		return true;
	}
}