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Find/ search String object from arraylist collection of objects – stream lambda java 8 (example)

Given an arraylist collection of String objects, We would like to find object from arraylist. We will iterate through the list of String objects using stream lambda in java 8.
We will perform following operations.

  1. Create the ArrayList collection of String objects.
  2. Iterate through the arraylist of objects using java 8 Stream.
  3. Find or Search element from arraylist.
  4. Print the query result.

Code – find or search String from arraylist of objects (stream lambda java8)

package org.learn;

import java.util.ArrayList;
import java.util.List;
import java.util.Optional;

public class FindElementInList {

	public static void main(String[] args) {
		// Remove nulls from List
		List<String> stringList = new ArrayList<String>();
		stringList.add("Soccer");
		stringList.add("Rugby");
		stringList.add(null);
		stringList.add("Badminton");
		stringList.add(null);
		stringList.add("Golf");
		stringList.add(null);
		stringList.add("Tennis");
		System.out.println(stringList);
		
		//Example 1 
		//Finding element in list
		final String query = "badminton";
		System.out.println("Finding " + query + " in games");

		Optional<String> queryResult = stringList.stream()
				.filter(value -> value != null)
				.filter(value -> value.equalsIgnoreCase(query))
				.findFirst();
		if (queryResult.isPresent()) {
			System.out.println("Found " + query + " in list");
		} else {
			System.out.println("Could not find " + query + " in list");
		}
		
		//Example 2 
		//Finding element in list
		final String search = "shooting";
		System.out.println("Finding " + search + " in games");
		queryResult = stringList.stream()
				.filter(value -> value != null)
				.filter(value -> value.equalsIgnoreCase(search))
				.findFirst();
		if (queryResult.isPresent()) {
			System.out.println("Found " + search + " in list");
		} else {
			System.out.println("Could not find " + search + " in list");
		}
	}
}

Output – find or search String from arraylist of objects (stream lambda java8)

[Soccer, Rugby, null, Badminton, null, Golf, null, Tennis]
Finding badminton in games
Found badminton in list
Finding shooting in games
Could not find shooting in list
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