将集合中的信息写入文件,-爱代码爱编程
package com.rick;
public class Student {
private String id;
private String name;
private String age;
private String address;
public Student() {
super();
}
public Student(String id, String name, String age, String address) {
super();
this.id = id;
this.name = name;
this.age = age;
this.address = address;
}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getAge() {
return age;
}
public void setAge(String age) {
this.age = age;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
@Override
public String toString() {
return "Student [id=" + id + ", name=" + name + ", age=" + age + ", address=" + address + "]";
}
}
package com.rick;
import java.io.*;
import java.util.*;
public class ArrayListToFile {
public static void main(String[] args) throws IOException {
//创建学生集合
ArrayList<Student> array = new ArrayList<Student>();
Scanner sc = new Scanner(System.in);
//循环添加学生
System.out.println("添加几个学生?");
int num = sc.nextInt();
for (int i = 0; i < num; i++) {
addStudent(array);
}
//创建输出缓冲流对象
BufferedWriter bw = new BufferedWriter(new FileWriter("student.txt"));
//循环输出到文件
for (Student student : array) {
System.out.println(student.toString());
bw.write(student.getId()+","+student.getName()+","+student.getAge()+","+student.getAddress());
bw.newLine();
}
bw.close();
}
public static void addStudent(ArrayList<Student> array) {
Scanner sc = new Scanner(System.in);
String id;
// 判断学号是否存在
while (true) {
System.out.println("请输入学生学号:");
id = sc.nextLine();
boolean flag = false;
for (int i = 0; i < array.size(); i++) {
Student s = array.get(i);
if (s.getId().equals(id)) {
flag = true;
break;
}
}
if (flag == true) {
System.out.println("该学生已存在,请重新输入:");
} else {
break;
}
}
System.out.println("请输入学生姓名:");
String name = sc.nextLine();
System.out.println("请输入学生年龄:");
String age = sc.nextLine();
System.out.println("请输入学生住址:");
String address = sc.nextLine();
Student s = new Student();
s.setId(id);
s.setName(name);
s.setAge(age);
s.setAddress(address);
//添加到集合
array.add(s);
System.out.println("添加成功!");
}
}
package com.rick;
import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
public class FileToArrayList {
public static void main(String[] args) throws IOException {
//创建一个输入缓冲对象
BufferedReader br = new BufferedReader(new FileReader("student.txt"));
//创建集合对象
ArrayList<Student> array = new ArrayList<Student>();
//读取文件
String line;
while((line = br.readLine()) != null){//br.read.line读一行
String[] strs = line.split(",");//分割
Student s = new Student();
s.setId(strs[0]);
s.setName(strs[1]);
s.setAge(strs[2]);
s.setAddress(strs[3]);
array.add(s);
}
//释放资源
br.close();
//打印到控制台
for (Student student : array) {
System.out.println("学号:"+student.getId()+" 姓名:"+student.getName()
+" 年龄:"+student.getAge()+" 地址:"+student.getAddress());
}
}
}`
版权声明:本文为博主原创文章,遵循 CC 4.0 BY-SA 版权协议,转载请附上原文出处链接和本声明。 本文链接: https://blog.csdn.net/qq_52000019/article/details/111093310