一步一步學lucene——（第三步：索引篇）
阿新 • • 發佈：2022-05-04
package ly;
/*
* 1.做一個圖書類Book id,name,price ,get,set訪問器，構造方法2個，1個無參，1個有參
做一個測試類，在main中建立3個圖書物件，放到list集合中。做一個選單，可以新增，刪除，修改，查詢
*/
public class Book {
private Integer id;
private String name;
private Integer price;
public Book(Integer id, String name, Integer price) {
super();
this.id = id;
this.name = name;
this.price = 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 Integer getPrice() {
return price;
}
public void setPrice(Integer price) {
this.price = price;
}
public Book(){
super();
}
public String toString() {
return "book [id=" + id + ", name=" + name + ", price=" + price + "]";
}
}package ly;
import java.util.List;
import java.util.ArrayList;
import java.util.Scanner;
public class test {
static java.util.List<Book> list=new ArrayList<Book>();
static{
Book book1=new Book(1,"紅樓夢",30);
Book book2=new Book(2,"西遊記",25);
Book book3=new Book(3,"三國演義",31);
list.add(book1);
list.add(book2);
list.add(book3);
}
public static void main(String[] args) {
while(true){
System.out.println("1.新增");
System.out.println("2.刪除");
System.out.println("3.修改");
System.out.println("4.查詢");
System.out.println("5.退出");
System.out.println("請選擇");
Scanner scanner=new Scanner(System.in);
int a=scanner.nextInt();
switch (a) {
case 1:
add();
break;
case 2:
del();
break;
case 3:
change();
break;
case 4:
search();
break;
case 5:
System.out.println("退出成功");
return;
}
}
}
private static void search(){
for(Book book4:list){
System.out.println(book4);
}
}
private static void change(){
System.out.println("請輸入需要修改的圖書編號");
int update=new Scanner(System.in).nextInt();
for(Book book:list){
if(update==book.getId()){
System.err.println("請輸入書名");
String name1=new Scanner(System.in).next();
System.err.println("請輸入價格");
int price1=new Scanner(System.in).nextInt();
book.setName(name1);
book.setPrice(price1);
System.out.println("修改成功");
}
}
}
private static void del(){
System.out.println("請輸入刪除的圖書編號");
int id=new Scanner(System.in).nextInt();
try{
for(Book book:list){
if(list.size()!=0){
if(id==book.getId()){
list.remove(book);
System.out.println("刪除成功");
}
}
}
}catch(Exception e){
}
}
private static void add(){
Scanner scanner=new Scanner(System.in);
System.err.println("請輸入編號");
int idd=scanner.nextInt();
System.err.println("請輸入書名");
String name2=scanner.next();
System.err.println("請輸入價格");
int price2=scanner.nextInt();
Book book=new Book(idd,name2,price2);
list.add(book);
System.out.println("新增成功");
}
}2.上題的類，在一個JSP頁面中，建立一個集合，裡面放3個圖書，集合迴圈遍歷顯示在頁面上。
<%@page import="ly.Book" %>
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<html>
<%
List<Book> list =new ArrayList<Book>();
Book book1 =new Book(1,"紅樓夢",30);
list.add(book1);
Book book2 =new Book(2,"西遊記",25);
list.add(book2);
Book book3 =new Book(3,"三國演義",31);
list.add(book3);
for (Book book4 : list) {
out.print(book4+"<br>");
}
%>
<body>
</body>
</html>3.在MySQL中建立Book表，裡面id,name,price,
create table book( id int(10) auto_increment primary key, name varchar(30), price double(5,2));
用命令實現，
新增一個圖書，
insert into Book(id,name,price)values(1,"java",88);
根據名稱刪除圖書，
delete from book where name='紅樓夢';
把所有名稱是“我”開頭的圖書刪除，
delete from book where name like '我%';
刪除全部圖書，
delete from book;
把20元以上的圖書價格都修改為18.8，
update book set price=18.8 where price>20;
檢視全部圖書，
select * from book;
檢視價格高於10塊錢的全部圖書
select * from book where price>10;