lang3
Find elements in an array
With this example we are going to demonstrate how to find elements in an array. We are using the org.apache.commons.lang3.ArrayUtils
class, that provides operations on arrays, primitive arrays (like int[]) and primitive wrapper arrays (like Integer[]). In short, to find elements in an array you should:
- Create a String array.
- Use
contains(Object[] array, Object objectToFind)
method ofArrayUtils
to check if the object is in the given array. - Use the
indexOf(Object[] array, Object objectToFind)
method find the index of the given object in the array. - Use the
lastIndexOf(Object[] array, Object objectToFind)
method to find the last index of the given object within the array.
Let’s take a look at the code snippet that follows:
package com.javacodegeeks.snippets.core; import org.apache.commons.lang3.ArrayUtils; public class FindIndexes { public static void main(String[] args) { String[] fruits = { "Orange", "Apple", "Blueberry", "Guava" , "Apple", "Peach", "Orange", "Strawberry" }; // Check if fruits array contains Guava boolean contains = ArrayUtils.contains(fruits, "Guava"); System.out.println("Contains Guava? Answer = " + contains); // Find the index of Blueberry int indexOfBlueberry = ArrayUtils.indexOf(fruits, "Blueberry"); System.out.println("index of Blueberry = " + indexOfBlueberry); // Find the index of first Orange int indexOfOrange = ArrayUtils.indexOf(fruits, "Orange"); System.out.println("index of Orange = " + indexOfOrange); // Find the last index of Orange int lastIndexOfOrange = ArrayUtils.lastIndexOf(fruits, "Orange"); System.out.println("last index of Orange = " + lastIndexOfOrange); } }
Output:
Contains Guava? Answer = true
index of Blueberry = 2
index of Orange = 0
last index of Orange = 6
This was an example of how to find elements in an array in Java.