第九周作业
1.做一个图书类Book id,name,price ,get,set访问器,构造方法2个,1个无参,1个有参做一个测试类,在main中创建3个图书对象,放到list集合中。做一个菜单,可以添加,删除,修改,查询
public class Book {
private Integer id;
private String name;
private double price;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public double getPrice() {
return price;
}
public void setPrice(double price) {
this.price = price;
}
public Book(Integer id, String name, double price) {
super();
this.id = id;
this.name = name;
this.price = price;
}
public Book() {
super();
}
}
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
public class Text1 {
public static void main(String[] args) {
List<Book> list = new ArrayList<Book>();
Book book = new Book();
Book b1 = new Book(1, "默读", 120);
Book b2 = new Book(2, "一级律师", 90);
Book b3 = new Book(3, "Romeo and Juliet", 134);
list.add(b1);
list.add(b2);
list.add(b3);
show(list, book);
}
public static void show(List<Book> list, Book book) {
System.out.println("1.添加图书");
System.out.println("2.删除图书");
System.out.println("3.修改图书");
System.out.println("4.查询图书");
System.out.println("请选择");
select(list, book);
}
public static void select(List<Book> list, Book book) {
int i = new Scanner(
System.in).nextInt();
switch (i) {
case 1:
System.out.println("请添加图书的编号:");
book.setId(new Scanner(
System.in).nextInt());
System.out.println("请添加图书的名称:");
book.setName(new Scanner(
System.in).next());
System.out.println("请添加图书的价格:");
book.setPrice(new Scanner(
System.in).nextDouble());
list.add(book);
System.out.println("添加成功");
show(list, book);
break;
case 2:
System.out.println("请输入要删除图书的名称:");
String name=new Scanner(
System.in).next();
for (int j = 0; list != null && j < list.size(); j++) {
if (list.get(j).getName().equals(name)) {
list.remove(j);
}
}
System.out.println("删除成功");
show(list, book);
break;
case 3:
System.out.println("请输入要修改图书的编号:");
int k=new Scanner(
System.in).nextInt();;
for (int j = 0; list != null && j < list.size(); j++) {
if (list.get(j).getId().equals(k)) {
list.remove(j);
System.out.println("请输入修改后图书的名称:");
String name1=new Scanner(
System.in).next();
System.out.println("请输入修改后图书的价格:");
double price1=new Scanner(
System.in).nextDouble();
Book b=new Book(k,name1,price1);
list.add(b);
break;
}
}
System.out.println("修改成功");
show(list, book);
break;
case 4:
for (int j = 0; list != null && j < list.size(); j++) {
System.out.println(list.get(j).getId() + "."
+ list.get(j).getName() + "," + list.get(j).getPrice());
}
show(list, book);
break;
}
}
}
2.上题的类,在一个JSP页面中,创建一个集合,里面放3个图书,集合循环遍历显示在页面上。
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%> <%@ page import="homework.Book"%> <% String path = request.getContextPath(); String basePath = request.getScheme() + "://" + request.getServerName() + ":" + request.getServerPort() + path + "/"; %> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>My JSP 'index.jsp' starting page</title> </head> <body> <% List<Book> listbooks = new ArrayList<Book>(); Book b1 = new Book("1", "网络安全技术", 66); listbooks.add(b1); Book b2 = new Book("2", "JSP实用教程",55); listbooks.add(b2); Book b3 = new Book("3", "JavaScript", 44); listbooks.add(b3); for (int i = 0; listbooks != null && i < listbooks.size(); i++) { out.print(listbooks.get(i).getId() + ": " + listbooks.get(i).getName() + " " + listbooks.get(i).getPrice() + "<br>"); } %> </body> </html>
3.在MySQL中创建Book表,里面id,name,price,
用命令实现,
添加一个图书,
根据名称删除图书,
把所有名称是“我”开头的图书删除,
删除全部图书,
把20元以上的图书价格都修改为18.8,
查看全部图书,
查看价格高于10块钱的全部图书
DROP TABLE IF EXISTS `book`; CREATE TABLE `book` ( `id` int(11) NOT NULL AUTO_INCREMENT COMMENT '图书编号', `name` varchar(25) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL COMMENT '图书名称', `price` decimal(10, 2) NOT NULL COMMENT '图书价格', PRIMARY KEY (`id`) USING BTREE ); INSERT INTO `book` VALUES (1, '水浒传', 50.90); INSERT INTO `book` VALUES (2, '红楼梦', 40.50); INSERT INTO `book` VALUES (3, '西游记', 45.90); INSERT INTO `book` VALUES (4, '我的第一本书', 20.00); UPDATE `book` SET `price`=18.8 WHERE `price`>20; SELECT * FROM `book`; SELECT * FROM `book` WHERE `price`>10; DELETE FROM `book` WHERE `name` LIKE '我%'; DELETE FROM `book`;