java手机进库程序：txt文件当做小型数据库实现增删改查，存储json数据到txt实体类的序列化和反序列化，修改txt中内容，Jackson操作，io流写入和输出
package com.lvyp.sprintboottest01.jacksonTest;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.lvyp.sprintboottest01.bean.Phone;
import java.io.*;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
public class PhoneTest {
private static final ObjectMapper mapper = new ObjectMapper(); // jackson主要操作类
// 将json字符串反序列化为实体类存入list集合并返回
public static List<Phone> read() throws IOException {
BufferedReader reader = new BufferedReader(new FileReader("./SprintBootTest01/src/main/resources/static/"));
String info = null;
ArrayList<Phone> list = new ArrayList<>();
for (int i = 0; (info = reader.readLine())!=null; i++) {
Phone phone = mapper.readValue(info, Phone.class);
list.add(phone);
}
return list;
}
// scanner接收数据返回实体类
public static Phone scanValue(){
Scanner scan = new Scanner(System.in);
Phone phone = new Phone();
System.out.print("品牌型号：");
phone.setPhoneName(scan.next());
System.out.print("尺寸：");
phone.setSize(scan.nextDouble());
System.out.print("价格：");
phone.setPrice(scan.nextDouble());
scan.nextLine();// 先将double的回车读取了
System.out.print("配置：");
phone.setConfig(scan.nextLine());
System.out.print("库存：");
phone.setStoreAmount(scan.nextInt());
System.out.println("");
return phone;
}
// 插入方法
public static void write() throws IOException {
BufferedWriter writer = new BufferedWriter(new FileWriter("./SprintBootTest01/src/main/resources/static/",true));
BufferedReader reader = new BufferedReader(new FileReader("./SprintBootTest01/src/main/resources/static/"));
Phone phone = scanValue();
phone.setSumPrice(phone.getPrice()*phone.getStoreAmount());
String info = null;
Phone readValue;
int flag = 0;
while ((info = reader.readLine())!=null) {
readValue = mapper.readValue(info, Phone.class);
if ((phone.getPhoneName().equals(readValue.getPhoneName()))){
flag = 1;
break;
}
}
if(flag == 0){
String s = mapper.writeValueAsString(phone);
writer.write(s+"\r\n");
writer.close();
System.out.println("插入成功");
return;
}
System.out.println("插入失败");
}
// 更新方法
public static void update() throws IOException {
BufferedWriter writer = null;
Scanner scanner = new Scanner(System.in);
List<Phone> phoneList = read();
System.out.println("请输入要修改的手机名字");
String phoneName = scanner.next();
int i;
int flag = 0;
for (i = 0; i < phoneList.size(); i++) {
if ((phoneList.get(i).getPhoneName().equals(phoneName))) {
flag = 1;
break;
}
}
if (flag == 0) {
System.out.println("没有此手机");
return;
}
System.out.println("请输入要修改的内容：输入1修改名字，输入2修改尺寸，输入3修改价格，输入4修改配置，输入5修改库存");
int num = scanner.nextInt(); // 要修改的项
switch (num){
case 1:
phoneList.get(i).setPhoneName(scanner.next());
break;
case 2:
phoneList.get(i).setSize(scanner.nextDouble());
break;
case 3:
phoneList.get(i).setPrice(scanner.nextDouble());
break;
case 4:
phoneList.get(i).setConfig(scanner.next());
break;
case 5:
phoneList.get(i).setStoreAmount(scanner.nextInt());
break;
}
// 先清空一次，只要实例化字符输出流就会清空文件的内容
writer = new BufferedWriter(new FileWriter("./SprintBootTest01/src/main/resources/static/"));
// 写入文件
for (int j = 0; j < phoneList.size(); j++) {
String str = mapper.writeValueAsString(phoneList.get(j));
writer.write(str+"\r\n");
}
writer.close();
}
// 展示清单功能1
public static void show () throws IOException {
List<Phone> phones;
phones = read();
double sum =0;
int sumAmount = 0;
if (phones.size()==0){
System.out.println("清单为空");
return;
}
System.out.println("---------------------------库存清单-------------------");
System.out.println("型号 尺寸 价格 配置 库存数量 总价格");
for (int j = 0; j < phones.size(); j++) {
System.out.println(phones.get(j).getPhoneName()+" "+
phones.get(j).getSize()+" "+
phones.get(j).getPrice()+" "+
phones.get(j).getConfig()+" "+
phones.get(j).getStoreAmount()+" "+
phones.get(j).getSumPrice());
sum = sum + phones.get(j).getSumPrice();
sumAmount = sumAmount + phones.get(j).getStoreAmount();
}
System.out.println("-------------------------------------------------");
System.out.println("总库存："+sum);
System.out.println("库存总价："+sumAmount);
}
public static void main(String[] args) throws IOException {
Scanner scanner = new Scanner(System.in);
while(true){
System.out.println("输入1查看清单，输入2插入,输入3修改，输入4退出");
int i = scanner.nextInt();
if (i == 1){
show ();
} else if (i == 2){
write();
} else if (i==3){
update();
} else if (i==4){
return;
}else {
System.out.println("输入错误，重新输入");
}
}
}
}