lombda use record

// string array is divided 
int [] = {ARR . 1 , 2 , . 3 , . 4 }; 
        
String str1 = Arrays.stream (ARR) .boxed () Map (I -> i.ToString ()). // ordinary arrays must be boxed in order to map inside toString 
                .collect (Collectors.joining ( "" )); 

 
String str2 .. = Arrays.stream (arr) .boxed () map (i -> i.ToString ()) the reduce ( "" , String :: concat); 
        
        
String str3 = Arrays.stream (arr) .boxed () the Map (Object :: toString) .reduce (. "" , String :: concat); // method reference Object :: toString