Spring构建CSV字符串并使用它下载文件

import com.opencsv.CSVWriter;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.ResponseBody;

import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;

@Controller
public class CSVController {

    @GetMapping("/download")
    public void downloadCSV(HttpServletResponse response) throws IOException {
        // 创建数据列表
        List<Person> persons = new ArrayList<>();
        persons.add(new Person("John", "Doe", 25));
        persons.add(new Person("Jane", "Smith", 30));

        // 创建CSVWriter对象
        PrintWriter writer = response.getWriter();
        CSVWriter csvWriter = new CSVWriter(writer);

        // 写入CSV头部
        csvWriter.writeNext(new String[]{"First Name", "Last Name", "Age"});

        // 写入CSV数据
        for (Person person : persons) {
            csvWriter.writeNext(new String[]{person.getFirstName(), person.getLastName(), String.valueOf(person.getAge())});
        }

        // 关闭CSVWriter
        csvWriter.close();

        // 设置响应头部
        response.setContentType("text/csv");
        response.setHeader("Content-Disposition", "attachment; filename=\"data.csv\"");
    }

    private static class Person {
        private String firstName;
        private String lastName;
        private int age;

        public Person(String firstName, String lastName, int age) {
            this.firstName = firstName;
            this.lastName = lastName;
            this.age = age;
        }

        public String getFirstName() {
            return firstName;
        }

        public String getLastName() {
            return lastName;
        }

        public int getAge() {
            return age;
        }
    }
}