String.join()方法示例详解

public static String join(CharSequence delimiter, CharSequence... elements)

public static String join(CharSequence delimiter, Iterable<? extends CharSequence> elements)

String[] arr = {"apple", "banana", "orange"};
String str = String.join(",", arr); // 将字符串数组 arr 中的元素用逗号连接成一个字符串
System.out.println(str); // 输出：apple,banana,orange
List<String> list = Arrays.asList("apple", "banana", "orange");
str = String.join(",", list); // 将集合类 list 中的元素用逗号连接成一个字符串
System.out.println(str); // 输出：apple,banana,orange

public class Main {  
    public static void main(String[] args) {  
        String separator = ", ";  
        String[] strings = {"Hello", "world", "Java", "8"};  
        String result = String.join(separator, strings);  
        System.out.println(result);  // 输出: Hello, world, Java, 8  
    }  
}

public class Main { 
    public static void main(String[] args) { 
        String separator = ", "; 
        String[] strings = {"Hello"}; 
        String result = String.join(separator, strings); 
        System.out.println(result); // 输出: Hello 
    } 
}