This tutorial example will show you how to search an element in Java ArrayList in both case sensitive and case insensitive way.Case sensitive search

package com.roytuts.java.arraylist;

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

public class SearchInArrayList {

	public static void main(String[] args) {

		List<String> list = new ArrayList<>();
		list.add("A");
		list.add("B");
		list.add("C");
		list.add("D");
		list.add("E");

		boolean found = list.contains("a");
		System.out.println("element a : " + (found ? "found" : "not found"));

		found = list.contains("B");
		System.out.println("element B : " + (found ? "found" : "not found"));

		int index = list.indexOf("c");
		System.out.println("element c : "
				+ (index <= 0 ? "not found" : "found"));

		index = list.indexOf("C");
		System.out.println("element C : "
				+ (index <= 0 ? "not found" : "found"));

	}

}

Output

element a : not found
element B : found
element c : not found
element C : found

Case insensitive search

package com.roytuts.java.arraylist;

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

public class SearchInArrayListCaseInsensitive {

	private boolean contains(String str, List<String> list) {
		for (String s : list) {
			if (str.equalsIgnoreCase(s))
				return true;
		}
		return false;
	}

	private int indexOf(String str, List<String> list) {
		if (str != null) {
			for (int i = 0; i < list.size(); i++) {
				if (str.equalsIgnoreCase(list.get(i))) {
					return i;
				}
			}
		}
		return -1;
	}

	public static void main(String[] args) {
		SearchInArrayListCaseInsensitive insensitive = new SearchInArrayListCaseInsensitive();
		List<String> list = new ArrayList<>();
		list.add("A");
		list.add("B");
		list.add("C");
		list.add("D");
		list.add("E");

		boolean found = insensitive.contains("a", list);
		System.out.println("element a : " + (found ? "found" : "not found"));

		found = insensitive.contains("B", list);
		System.out.println("element B : " + (found ? "found" : "not found"));

		int index = insensitive.indexOf("c", list);
		System.out.println("element c : "
				+ (index <= 0 ? "not found" : "found"));

		index = insensitive.indexOf("C", list);
		System.out.println("element C : "
				+ (index <= 0 ? "not found" : "found"));

	}

}

Output

element a : found
element B : found
element c : found
element C : found

Thanks for reading.

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