创建从任何自定义对象类型创建csv字符串的方法-泛型

import java.lang.reflect.Field;
import java.util.List;
import java.util.stream.Collectors;

public class CsvUtil {
    public static <T> String createCsvString(List<T> objects) {
        if (objects == null || objects.isEmpty()) {
            return "";
        }
        
        // 获取对象的所有字段
        Class<?> clazz = objects.get(0).getClass();
        Field[] fields = clazz.getDeclaredFields();
        
        // 构建CSV标题行
        String header = String.join(",", getFieldNames(fields));
        
        // 构建CSV数据行
        String data = objects.stream()
                .map(obj -> getFieldValues(obj, fields))
                .map(values -> String.join(",", values))
                .collect(Collectors.joining("\n"));
        
        return header + "\n" + data;
    }
    
    private static List<String> getFieldNames(Field[] fields) {
        return List.of(fields).stream()
                .map(Field::getName)
                .collect(Collectors.toList());
    }
    
    private static List<String> getFieldValues(Object object, Field[] fields) {
        return List.of(fields).stream()
                .map(field -> {
                    field.setAccessible(true);
                    try {
                        Object value = field.get(object);
                        return value != null ? value.toString() : "";
                    } catch (IllegalAccessException e) {
                        return "";
                    }
                })
                .collect(Collectors.toList());
    }
}

public class Main {
    public static void main(String[] args) {
        List<Person> persons = List.of(
                new Person("John", 25),
                new Person("Alice", 30),
                new Person("Bob", 35)
        );
        
        String csvString = CsvUtil.createCsvString(persons);
        System.out.println(csvString);
    }
}

class Person {
    private String name;
    private int age;
    
    public Person(String name, int age) {
        this.name = name;
        this.age = age;
    }
    
    // 省略getter和setter方法
}

name,age
John,25
Alice,30
Bob,35