find out all the numbers starting with 1 using java8 Stream functions?

There are following way to find out all the numbers starting with 1 using java8 Stream functions.

• First convert Arrays to list using Arrays.asList() method.
• Now get the Stream data from List using arrayList.stream() method.
• Inside filter we call to startsWith() method to check if a string starts with the given prefix.
• Now call the Collectors.toList() to store all number inside list.
• From Collectors.toList() method we are collect all elements which start with 1.
• print the number.

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

public class Example {
	public static void main(String[] args) {
		List<Integer> number = Arrays.asList(1, 4, 45, 120, 67, 31, 140, 561, 100);
		List<Integer> listNum = number.stream().filter(d -> String.valueOf(d).startsWith("1"))
				.collect(Collectors.toList());
		System.out.println("find out all the numbers starting with 1 :- " + listNum);
	}
}

Output :-

find out all the numbers starting with 1 :- [1, 120, 140, 100]