I have the output of my array that looks like 123611 (example numbers).
I am trying to get the output to be nicely formatted 1,2,3,6,11
I have not been around Java too much and I cannot remember how to go about doing this. Thanks!!
Here is my code:
int array3[] = { 1, 2, 3, 6, 11 };
for (int i = 0; i < array3.length; i++)
System.out.print(array3[i]);
You can use Streams available from Java 8, Note here I'm using the integer wrapper class Integer, not the primitive type int
Integer array3[] = { 1, 2, 3, 6, 11 };
System.out.println(Stream.of(array3)
.collect(Collectors.mapping(String::valueOf, Collectors.joining(",")))
);
As @Jelaby mentioned, it's better to use map(), which converts each Integer to String first, then join it
Integer array3[] = { 1, 2, 3, 6, 11 };
System.out.println(Stream.of(array3)
.map(String::valueOf)
.collect( Collectors.joining(",")));
IntStream from an int array with Arrays.stream(), and I would say that using map() or mapToObj() to transform the stream is more idiomatic than using a mapping collector. For example: Arrays.stream(array3).mapToObj(String::valueOf).collect(Collectors.joining(",")) (if using Integer instead of int you'd use map instead of mapToObj).
You simply need to print them as well =)
for(int i=0; i< array3.length; i++)
System.out.print(array3[i] + (i <array3.length-1 ? ",":"") );
This is will leave the trailing comma off, and print one between each entry
Here is an easy way to do this:
import java.util.Arrays;
public class SO {
public static void main(String[] args){
int[] a = {1,2,3,6,11};
System.out.println(Arrays.toString(a));
}
}
This outputs:
[1, 2, 3, 6, 11]
Or you can strip out the chars you don't want like this:
System.out.println(Arrays.toString(a).replaceAll("\\[|\\]|\\s", ""));
Which outputs:
1,2,3,6,11
You can print , after each element except last one using this loop
for (int i = 0; i < array3.length - 1; i++)
System.out.print(array3[i] + ", ");
and later print last element of array without , after it.
System.out.println(array3[array3.length - 1]);
Or just use
String arrStr = Arrays.toString(array3);//will produce "[1, 2, 3, 6, 11]"
System.out.println(arrStr);
//if you want to remove [...] brackets you can substring them with
System.out.println(arrStr.substring(1,arrStr.length()-1));
I would bet this is what you're looking for:
Arrays.toString(array3);
The output is:
[1, 2, 3, 6, 11]
If you don't want the square brackets, just strip them.
int array3[] = { 1, 2, 3, 6, 11 };
String s ="";
for (int i = 0; i < array3.length-1; i++){
s +=array3[i]+", ";
}
s +=array3[array3.length-1];
System.out.print(s);
is essentially the same as Array.toString() but without [],
and doesn't use if statment or ternary (?:) in each iteration to check if it's the last element.In genaral, building a String first, is a better practice, because its faster and you get a string to process, System.out and its gone.
