ListString 换成以分割的字符串

要将List转换为以","分割的字符串，可以使用Java 8的Stream API和Collectors.joining()方法。以下是一个示例代码：

import java.util.Arrays;
import java.util.List;
import java.util.stream.Collectors;

public class Main {
    public static void main(String[] args) {
        List<String> list = Arrays.asList("apple", "banana", "orange");
        
        String result = list.stream()
                .collect(Collectors.joining(","));
                
        System.out.println(result);
    }
}

输出结果为：apple,banana,orang