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July 11, 2025 - In this approach, we will convert the array into ArrayList, and then we will use the indexOf method of ArrayList to get the index of the element. ... // Java program to find index of an array // element using ArrayList indexOf() Method import java.util.ArrayList; public class Geeks { public static int findIndex(int arr[], int t){ ArrayList<Integer> clist = new ArrayList<>(); // adding elements of array // to ArrayList for (int i : arr) clist.add(i); return clist.indexOf(t); } public static void main(String[] args){ int[] a = { 5, 4, 6, 1, 3, 2, 7, 8, 9 }; int t = 7; System.out.println(findIndex(a, t)); } }

December 7, 2023 - After the input array is converted into a list, we use the indexOf() method to find the index of our target element.

April 21, 2026 - Java™ Platform Standard Ed. 8 ... This class contains various methods for manipulating arrays (such as sorting and searching).

March 27, 2024 - Almost there... just a few more seconds

August 12, 2022 - I am not able to find it. I have searched everywhere so where is java array indexof?

November 18, 2023 - The indexOf method in Java is a vital utility used to locate the index position of a particular element or substring within various data structures such as strings and arrays. It is part of the String class and List interface, offering a convenient ...

February 12, 2023 - The .indexOf() method returns the index of the first occurrence of the specified element in an ArrayList. If the element is not found, -1 is returned. ... Looking for an introduction to the theory behind programming?

August 19, 2024 - This method accepts a single argument, Object o, which represents the element you wish to find within the ArrayList. If the specified element is present in the list, indexOf() returns the zero-based index of its first occurrence.

July 19, 2009 - Mike Osterhout wrote:the indexes of the array. Arrays are indexed via a number -- so an array of size 5 has the indexes 0, 1, 2, 3, and 4. Is that what you want? Henry · Books: Java Threads, 3rd Edition, Jini in a Nutshell, and Java Gems (contributor)

July 31, 2023 - If the component isn't found, the indexOf strategy returns -1. import java.util.ArrayList; import java.util.List; public class ArrayIndexFinder { public static int findIndexApproach3(int[] array, int element) { List<Integer> list = new ArrayList<>(); for (int i : array) { list.add(i); } return list.indexOf(element); } public static void main(String[] args) { int[] array = {1, 2, 3, 4, 5}; int element = 4; int index = findIndexApproach3(array, element); System.out.println("Index of element " + element + ": " + index); } }

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java.lang.Object | +----array.Index · public final class Index · extends Object Index = represents an index set to arrays · Ranges provide the support to extract and operate on regular array sections. Indexes provide similar support for irregular sections.

October 19, 2013 - And, more importantly, what does it take as a parameter? What is your for loop doing? indexOf() is supposed take in the index of i in the array. My for loop takes me through the entire array. On a side note, this is for an assignment, and we're required to use .equals as part of this code.

returns the position of the specified element from the arraylist · Note: If the specified element doesn't exist in the list, the indexOf() method returns -1. import java.util.ArrayList; class Main { public static void main(String[] args) { // create an ArrayList ArrayList<Integer> numbers ...

January 13, 2023 - ArrayList<String> list = new ArrayList<>(Arrays.asList("alex", "brian", "charles","alex",","alex","harry")); int index = list.indexOf("alex"); System.out.println(index);

List has indexOf method, so we can convert Array to List and call indexOf method on it. Following code shows how to do that. import java.util.Arrays; public class JavaArrays { public static void main(String[] args) { String[] colors = { "red", "green", "blue", "orange", "maroon" }; System.out.println(Arrays.asList(colors).indexOf("blue")); } }

Can you solve this real interview question? Peak Index in a Mountain Array - You are given an integer mountain array arr of length n where the values increase to a peak element and then decrease. Return the index of the peak element. Your task is to solve it in O(log(n)) time complexity.