Find Duplicates In Arraylist JavaJava: Detect duplicates in ArrayList? Simplest: dump the whole collection into a Set (using the Set(Collection) constructor or Set. Create a standalone maven project in Eclipse. asList(10, 20, 30, 40); To get the last element of a ArrayList in Java, we can use the list. Replace all occurrences of specified element of Java ArrayList…. asList("A", "B", "B", "C", "D", "D", "Z", "E", "E"); list. We can add or remove elements anytime. By using LinkedHashSet class, we can remove the duplicate element from the ArrayList…. Do you want to identify duplicates elements from Java …. ArrayList in Java is designed to store repeated elements where as HashSet only store unique elements, using that feature of HashSet in Java you can remove duplicates from ArrayList. In this solution to find duplicate elements in an array in Java, iteration of the array is done and elements of the array are added to the set. So we will then find out the elements that have frequency more than 1, which are the duplicate elements. Now, In the Map, If the number of occurrences is more than 1 then we are printing the word. To remove duplicates from array in java 8 use distinct() method. In order to find duplicates we can utilize the property of Set in Java that in Java duplicates are not allowed when going to be added in a Set. How to get all possible combinations of an array. Create a Map, and then iterate over your ArrayList. With a nested for-loop, we can check an ArrayList (or other array) for duplicate elements. Collect the elements to a List by calling the Collectors. asList(0, 1, 2, 3, 0, 0); List < Integer > listWithoutDuplicates = new ArrayList …. Any duplicates in the ArrayList would be discarded as HashSet stores only unique elements. Java Program to Remove duplicate elements from ArrayList. // more than 2 times in array so, // it will print duplicate value. Pandas how to find column contains a certain value Recommended way to install multiple Python versions on Ubuntu 20. test with myString to check if myString has any non-whitespace charac. List finalEmpList = removeDuplicateEmployee (empList); System. Explore various ways to calculate the count of duplicate elements in If we don't need the pre-Java 8 compatibility, we can simplify our . ArrayList in Java do not prevent the list from having duplicate values. Get Enumeration over Java ArrayList: 32. The array is a native programming component or data structure but ArrayList is a class from Java Collections framework, an API. Iterator; public class Arrlist { public static void main (String [] args) { ListIterator litr = null; ArrayList …. Below is the implementation of the above approach:. Remove Duplicates from ArrayList in Java. Create a list and add duplicate elements into it. distinct() method returns a stream consisting of the distinct elements ( . Here an array of integers is having 10 integers and 1 and 8 are duplicate integers. util One of the simplest ideas of an aggregate is a list of elements, like that which is provided by an array. The list is an interface in Java, which is a child interface of Collection. In the examples, we covered a basic Java solution, a solution using the …. Please find below the complete code. To check if ArrayList contains a specific object or element, use ArrayList. Next: Write a Java program to get the majority element from a given array of integers containing duplicates. Method 2 : Removing Duplicate Elements From ArrayList Using LinkedHashSet. set (arrayList_index,"New_Element") ArrayList_Name refers to the actual arraylist…. Algorithms - find duplicates in an array using java 1. How do you find duplicates in array of objects? Implementing The Logic To Find Duplicate How do you remove duplicates in Java? Approach: Get the ArrayList with duplicate values. Class) public Collection asUnmodifiable() Creates an unmodifiable view of a Collection. This class is available in java. Write a Java Program to Count Array Duplicates with an example. Pick from a List Multiple Lines. size()); • Java’s garbage collector finds objects that are no longer used (referenced) and destroys them –Our array list may interfere with this. How to Remove Duplicate Values From Java List/ArrayList?. Mongodb aggregate remove element from array. ArrayList list1 = new For removing duplicate entries, We are adding all items into a LinkedHashSet, which will remove the duplicate entries. [code]List strings = new ArrayList (); strings. Find similar string in arraylist. How to remove duplicate elements in ArrayList. In this article, we explored a few ways to find differences between lists. In order to find duplicates we can utilize the property of Set in Java that in Java duplicates …. 3: Traverse the ArrayList arr and check whether the ArrayList new_arr has the same element in it or not. The solution and logic shown in this article are generic and apply to an array of any type e. On popup window under Maven select Maven Project. Generate all combinations from multiple lists. Get the ArrayList with duplicate values. 5 methods to find duplicates in array in java : 1) Brute Force Method 2) Sorting Method 3) Using HashSet 4) Using HashMap 5) Using Java 8 …. Joshua Harris wrote:So, as the title says I'm trying to count the number of elements in an ArrayList which also have duplicates. We know that a set doesn’t allow any duplicate elements. Each integer can appear either once or twice and you need to find …. Similarly, the Collections has a built-in method “sort ()” that is used for sorting the Lists. random () with the (ArrayListSize) and typecast to an integer. How to get the duplicates values from Arraylist and the…. If an ArrayList have three duplicate elements, but at the end, only the ones which are unique are taken into the ArrayList and the repetitions are neglected can be done using various approaches discussed as below. java find duplicates in array Code Example. ? · Get the ArrayList with duplicate values. In this article, we will see how to find the duplicate strings and their counts from an ArrayList list = new ArrayList(. How to count duplicate values in HashMap in Java. ArrayList with duplicates: [DOJ, DOJ, MB, DR, AM] size of ArrayList without duplicates: 4. check if all values are same in list java. As mentioned previously, an ArrayList will automatically stretch on the addition of new elements and reduce in size when elements are removed. using namespace std; // Function to find the Duplicates, // if duplicate occurs 2 times or. See more ideas about lottery number generator, lottery numbers, number generator. 1: Create an ArrayList arr with duplicate elements. Now, the first thing I tried was to do something like this. List interface is implemented by the classes ArrayList, …. Removing duplicate elements from ArrayList in Java can be done using HashSet but that will not retain the order, LinkedHashSet will remove duplicate elements and also retain the order of the list. Now add all the bikes of the ArrayList to a SortedSet,and if there are duplicates add to the list of duplicates: List duplicates = new ArrayList(); …. Linked list implementation in java using generics. 3 Methods to Reverse an Array in Java. contains () method returns true if the object is present in the list, else the method returns false. How to Find K Missing Numbers in Integer. ( use of regex) Iterating in the array and storing words and all the number of occurrences in the Map. Quick solution: int occurrences = Collections. how to find the duplicate values in arraylist in java. If we change the object state inside the first ArrayList , then the changed object state will be reflected in the cloned ArrayList as well. Java Linkedlist Vs Arraylist. 3 Ways to Find Duplicate Elements in an Arr…. (There are 3 copy's) package domein; import java. Find duplicates in array list using Map with input order. In this scenario you need to write your custom logic to extract the duplicates from the list, you will get all the duplicates in the Person list. This post shows different ways to remove duplicate elements from ArrayList in Java. Next, use LinkedHashSet to remove the duplicates and preserve the order as in the original list. The collections in java provide an architecture to store and manipulate the group of objects, interfaces and classes. Traverse through the first arraylist and store the first appearance of each element into the second arraylist using contains () method. 0 See Also: Collections#unmodifiableCollection(java. In fact, ArrayList is internally implemented using an array. public static Set findDuplicates(List listContainingDuplicates) { ; 2 ; 3. Create a resultSet that will have all the duplicate integers. Hello Simon, Even if the ArrayList has duplicates, the minimum value above code finds remains the same. class Solution { public List findDuplicates(int[] nums) { int l=nums. Finding and printing duplicates in a string Arraylist-4. There are many methods through which you can find duplicates in array in java. To get distinct values, the distinct () method is an intermediate. Using HashSet to remove duplicate elements from ArrayList. it implements the list interface and extends the abstractlist class. How to print only duplicates in ArrayList?. We identified it from reliable source. Java programming interview questions on this keyword part 1. Now add all the bikes of the ArrayList to a SortedSet,and if there are duplicates add to the list of duplicates: List duplicates = new ArrayList(); Set bikeSet = new TreeSet(new bikeComparator()); for(bike c : originalbikeList) { if(!bikeSet. The problem, Find All Duplicates in an Array LeetCode Solution states that you are given an array of size n containing elements in the range [1,n]. Output: Original list values : [A, B, C, C, B, A] newlist values are : [A, B, C] 3. We will use Comparator to remove duplicate elements. Annotated Solution Guide for Thinking in Java Fourth Edition. We used List l1= new ArrayList(); here, we could take integer array but we didn't. The List interface in Java provides methods to be able to compare two Lists and find the common and missing items from the lists. Or how to write a Java Program to find and count the duplicates in a given array. Each element is stored as a node. Use a HashSet in removeDuplicates. How to Remove Duplicates from ArrayList in Java With Example. A LinkedList is a doubly-linked list/queue implementation. Java ArrayList class uses a dynamic array for storing the elements. ArrayList in Java is designed to store repeated elements where as HashSet only store unique elements, using that feature of HashSet in Java you can remove duplicates from ArrayList…. The object referenced by index 5 is no –Allows duplicates …. 30 lines (28 sloc) 797 Bytes Raw Blame Open with Desktop View blame /* package whatever; // don't place package name! */ import java. You'll start with a simple hello world program and proceed to cover common concepts such as Conditional Statements, Loop Statements, Math, and Logic in Java, before moving on to more advanced concepts like Inheritance, Generics, and ArrayLists…. Use addmethods to add to different …. Use steam's distinct () method which returns a stream consisting of …. Programming Questions on Array. Then you can add the Set again to the List after clearing the List. Using Iterator · Create another ArrayList. How to count duplicate elements in ArrayList?. How to populate a static List (ArrayList, LinkedList) in. Duplicates in an ArrayList can be removed. Linked list implementation in java using generics. That's too expensive considering algorithmic complexity. The following example shows how to use the smallest available font size in LaTeX ( \tiny) and the small caps ( \textsc {}) font style: This is a simple example …. found = true; } else { MessageBox. Below example removes duplicate String elements and maintains. Java 8 – Find duplicate elements in a Stream · 1. 3 digit number combinations generator. Set is used to take unique elements. Given an array a [] of size N which contains elements from 0 to N-1, you need to find all the elements occurring more than once in the given array. This interface is used to store an ordered collection of elements. Extract duplicate objects from a List in Java 8. The Java language supports arrays to store several objects. In Java Set (I) stores unique elements. how to check duplicate values in array java. Create another ArrayList ‘alNew’. It won't check for all occurrences. In the below program I have used HashSet and ArrayList to find duplicate words in String in Java. In this post, we are going to remove duplicate elements from ArrayList in Java. Example: Removing duplicates from List. Solution 4: Java 8 stream function. Unlike an array that has a fixed length, ArrayList …. Therefore, it can be used to remove duplicate elements. How to find duplicate elements in an array. Then the HashSet is converted back into an ArrayList i. Top Rated; Remove duplicates in an arraylist from a text file - java. There is a built in command in VBA for removing duplicates …. If it matches then its duplicate and if it doesn't, then there are no duplicates. Now I want to find if the ArrayList has duplicates based on these attributes (First Name, Last Name, NPI, Addresses). check if there is a duplicate in array list java; find duplicate elements in array in java; check for duplicates in array java; java find duplicates in array; java check for duplicates in array; count duplicate elements in array java; find duplicate elements in two arrays; duplicate number in array java; find duplicates java. Before java 8, sun people gave importance only for objects but in 1. Go to definition R; Copy path Copy permalink. Finally, the last method to find duplicates in an array is to use the for loop. Here is how we can find the duplicates in the array using this method: Create a HashSet that will store all the unique integers. Removing an element from Array using for loop. Java Program to find Sum of Elements in an Array. Count Unique Characters In A String. after setting the data in array list with duplicate values i want to check the no of occurances but its not finding out. *; public class JavaHungry { public static void main( String args []) { // Given String containing duplicate words String input = "Java is a programming language. add all elements from set to arraylist. ArrayList is one of the most commonly used collection classes of the Java Collection Framework because of the functionality and flexibility it provides. loop through rows of datatable. Here, we have several examples to illustrate the string to ArrayList …. if hashIndex [i]==1, element is duplcate. Show("Duplicate found"); obviously not a good way as you could have alot of items to get through. Create Map when the Key is the Value of Array and Value is counter. Can contain duplicates and elements are ordered. efficient way to check an array for no duplicates in java. How do I remove duplicates from an arraylist? If it's no problem to sort the list first, you can do it with a single loop (code is in VB. Here, we have used the LinkedHashSet to create a set. Collect all district elements as List using Collectors. Contrary to Arrays that are fixed in size, an ArrayList grows its size automatically when new elements are added to it. How to Create Excel Pivot Table in Java Application 0 ; solving a linear simultaneous equation of 10 variable 3 ; Java Programming ( Cashier Question ) 2 ; Java - Dice Game help 1 ; java 2 ; I need help in Java GUI 2 ; Mastermind game in java 1 ; Update the JDialog when it is opened but not visible 14 ; Bubble Sorting Java Code 2 ; i need help. Here is the function for doing this. A HashSet that records encountered elements is helpful. add(c); } } you may find all the duplicates. If your arraylist's size is within a fixed small range, then this is a great solution. How to remove duplicates elements from ArrayList in Java? Web Development Programming Core Java. That gives you the List without any duplicates. I have to make sure that I identify the duplicates and store the duplicates in another arrayList, duplicateRecords for the sake of …. Java program to print duplicates from a list of integers. Example 1: Remove duplicate elements from ArrayList using Set import java. An ArrayList in Java provides support for such a resizable list of elements with the freedom of addition, removal, finding, sorting, and replacement of objects in the list. Java Program To Check A Number is Palindrome or Not. Given an array of positive integers, find all the duplicates. As no additional buffers are used, this method of reversing an array in Java …. To remove the duplicates from the arraylist, we can use the java 8 stream api as well. Given two sorted arrays arr1 and arr2 of passport numbers, implement a function findDuplicates that returns an array of …. April 25, 2022; Output is the boolean value. Here is an example, that returns the last element 40 from the following ArrayList: import java. Just because we are not sure about the number of duplicate values, we are going to find. We will use ArrayList to provide a Stream of elements including duplicates. I want to be able to check through the arraylist and find out if the same string appears the same amount of times as there are attendees (meaning all attendees are free at that time). If an element is found to be a duplicate, that element should then be exempt from the search so if that element is found …. What you will learn here about java. Then the HashSet is converted back into an ArrayList. add (int index, E e): The add (int index, E e) method is used to add the specified element at a specific position in the ArrayList. By using HashSet, a general-purpose Set implementation, we can find duplicates in O(n) time. Also you can check the duplicates using ". Now we will see the below steps how to create a maven based Java project in Eclipse. To concatenate the two lists together we can create a new ArrayList, and then use addAll () function to add to it all elements from itemList1 and then add all elements from itemList 2 like so: List mergedList = new ArrayList…. Set will allow only unique elements. You can run this example from command line or Eclipse IDE, whatever suits you. CodeHS Practice is a curated list of practice problems to help students gain a stronger understanding of basic programming skills. What activity can be used to loop through each row from a datatable in uipath. java arrays arraylist duplicates Si "Block" se compara con un int, probablemente debería hacer que hashCode devuelva el mismo int y que los iguales comparen …. Answer (1 of 10): public void countDuolicate() { ArrayList al =new ArrayList ; al. Java Program to find duplicate elements in array Here is our three solutions packed into a Java program to find duplicate elements in array. Java 8 Object Oriented Programming Programming. We will also see how to remove duplicate objects from ArrayList in Java. How to Remove Duplicate Elements From an ArrayList in Java=====I have explain this first approach to remove dubl. ArrayList$[email protected] java. We can use for loop to populate the new array without …. How to Remove Duplicates from Array without using Java Collection API Read more: import java. Stream to remove duplicates from array in java. You can use lastIndexOf to check for duplicates for(int i =0; i < list. Moreover, why set interface does not allow duplicate values in Java?. This gives us a random ArrayList Index at any point of time and every time. How to count duplicate values in HashMap in Java; In java it is very easy to find count of duplicate values in java. This example demonstrates different ways to sort List of String objects in Ascending order using Java 8 Stream APIs: import java. Hi, I have searched high and low for a solution yet still no luck, I have two arraylists populate with FileInfo and I want to compare the two and write the duplicate (matching files) to a listbox. In this blog we will find Duplicate Records present in ArrayList and display those to a listbox. Find duplicates in a file. 2629,How to print only duplicates in ArrayList? tutorial, question, answer, example, Java, JavaScript, SQL, C, Android, Interview, Quiz, ajax, html. frequency(myArrayList, element); Practical example. test with myString to check if …. How to find duplicate elements in ArrayList gracefully?. The collection classes reside within the package: java. In addition to implementing the List interface, this class provides methods …. Since Java 8+, you can filter an ArrayList by using the Stream API. ArrayList is the most popular implementation of the List interface from Java’s Collection framework, but it allows duplicates. List equals () Method in Java …. Arrays; public class RemoveDupFromArray{ …. get () method takes index as an argument and returns the element present in the ArrayList at the index. How to Count Duplicate Elements in Arraylist. ArrayList list = new ArrayList(5); int last = list. Three ways we can write logic to remove duplicate elements from ArrayList: Using HashSet. To take input of an array, we must ask the user about the length of the array. Just make sure that name of your Java source file should be same as your public class e. Apart from that, you can query an ArrayList with it's own APIs such as get methods to return element by the specified index; indexOf methods to return index by the specified element; contains methods to check existing; size and isEmpty methods to check the ArrayList …. Next Post: Get Current Date and Time in Java…. public class CheckDuplictesInArray. length; j ++) {if (j != i && zipcodeList [j] == zipcodeList [i]) {duplicates = true;}}} Example 2: java find duplicates in array package dto; import java. An ordered group of elements can be stored in a java array list and duplicates …. I have also added video tutorial link at the end of this post. Insertion order is preserved which means that the …. The time complexity of this problem is O (n^2) or quadratic. ser” and make sure we cast the value into an ArrayList …. Therefore, it allows access using index values. When we used the indexOf () method to find …. Using the index, we can print both random index and random ArrayList …. By using HashSet class, we can remove the duplicate element from the ArrayList. how to find duplicates values + arraylist<> adnroid java. Algorithms – find duplicates in an array using java …. As ArrayList is index based collection, we can add an element at a specific index position. A code snippet which demonstrates this is as follows. Just check the count which will be equal to one for unique words. Contains() method of the arraylist collection to see if the item already exists, if so, then don't add it. How to get the duplicates values from Arraylist and then get those items in Step 3 − Add the following code to src/MainActivity. E) If present, do not add it to the newList. check if string contains duplicate characters java. Input can be given using CLIOutput will be shown in GUI / Window which is developed using Win32 SDK. I figured out how to output the Max/Min, sort, prompt to delete duplicates, but I can't for the life of me identify the duplicates. An ArrayList is a structure that stores a collection of objects inside itself as elements. “find duplicates in arraylist java” Code Answer's ; 1. Table of ContentsIntroductionUsing Collection’s removeIf() methodUsing ListIterator classUsing removeAll() methodUsing Java 8 Stream to filter List itemsConclusion Introduction In this tutorial, you will learn how to remove element from Arraylist in java while iterating using different implementations provided by Java. In this simple means of reversing a Java array, the algorithm is made to loop over the array and keeps swapping the elements until the midpoint is reached. Extract the unique entries in the list with the use of …. put ("stack", "overflow", "stack", "yahoo", "google", "msn", "MSN", "stack", "overflow", "user"); Map counts = new HashMap (); for (String str : strings) { if (counts. For-each input element, check whether there is any element with the same value. One of the most common ways to find duplicates is by using the brute force method, which compares each element of the array to every other . empty the arraylist using clear () method. This is also known as a brute force algorithm to find duplicate objects from Java array. Example 1: java array check duplicates duplicates = false; for (i = 0; i < zipcodeList. finding duplicates in arraylist by using contains method — oracl…. Show("Duplicate found"); } }} obviously not a good way as you could have alot of items to get through. It very simple example for removing duplicate items from ArrayList. Once you think that you’ve solved the problem, click below to see …. Java arraylist duplicate elements search Java arraylist duplicate elements search hi, please help me finding the no of duplicates elements in an arraylist example an arraylist …. This will remove the duplicates. count the duplicate elements in arraylist in java. HashSet; public class Program { static ArrayList removeDuplicates(ArrayList removeDuplicates (ArrayList So finally we have Set object in our hand, just pass this current Set object as argument to ArrayList…. In this short tutorial, we'll look at some different ways to count the duplicated elements in an ArrayList. How to map one object to another in java; How to map one object to another in java. Perform Binary Search on Java ArrayList: 34. ArrayList people2 = (ArrayList) readStream. HashSet is one of the methods to remove elements from ArrayList. addAll), then see if the Set has the same size as the ArrayList. An ArrayList is a resizable array that grows as additional elements are added. Selenium Webdriver with Java. println (“No Unique Employee Details Found…. Get the stream of elements in which the duplicates are to be found. Ever wondered how you can make an ArrayList unique? Well, in this article we'll be seeing how to prevent the addition of duplicates into our ArrayList. Leetcode / find-all-duplicates-in-an-array. // Store empty record slots to be removed ArrayList toRemove = new ArrayList. You’ll iterate over the given objects array and check if the unique items array contains the iterated object. how to find duplicates values + arraylist adnroid java. It is because it removes the duplicate elements and maintains insertion order. I was taking a test and was stuck with this program can someone help me find a solution? I want to remove all the. This will store all non duplicate elements in the new array list…. Answer (1 of 3): The idea behind the solution to any problem in problems like these is independent of the language used. Create a LinkedHashSet from this ArrayList. They are, remove (int index): accepts the index of the element to be removed. Big-O Complexity Access Θ(1) SearchΘ(n) InsertionΘ(n) DeletionΘ(n) Question: Write a program to implement your own Array List in Java. The complete code to print all elements of the ArrayList using all 4 techniques is given below: import java. In this post, we will learn to find duplicate elements in array in java using Brute Force method, using Sorting method, using HashSet, using HashMap and using Java 8 Streams. The syntax to get element from ArrayList is. 1) Store input values to the List. contains(element); Example 1 – Check if Element is present in ArrayList. All Java program needs one main() function from where it starts executing program. Replace All Elements Of Java ArrayList: 35. If String Arrays length is greater-than HashSet size then there are duplicate element/objects are present in original String Arrays. We can use Java 8 stream 's distinct () method to remove duplicates from the array in java…. 1: Create an ArrayList arr with duplicate. Solution for Write a program in Java using ArrayList to remove duplicates in the array {0,1,4,5,8,0,9,4}. In this program we will see that how to find the middle element of a given list in java. Mongodb aggregate remove element from array. Java answers related to "java find duplicates in array" efficient generic duplicate finding class java; java find duplicate element in list. Use steam's distinct() method which returns a stream consisting of the distinct elements comparing by object's equals() method. Following are the steps to merge the array list:. You can call contains () method on the ArrayList, with the element passed as argument to the method. Generate lottery numbers, check …. find duplicate numbers in java 2d array. Count Dim i As Integer For i = count - 1 To 1 Step -1 If (arr(i). In the examples, we covered a basic Java solution, a solution using the Streams API, and with third-party libraries like Google Guava and Apache Commons Collections. println(“unique set is…”+PlatformFactory. java How to find duplicates in an ArrayList? This is a pretty common question, but I could not find this part:Say I have this array . Contains() method of the arraylist collection to see …. Merge Two Arrays in Java without the duplicate elements in it. The List interface provides a special iterator, called a ListIterator, that allows element insertion and replacement, and bidirectional access in addition to the …. We need to pass the method with the index of the element and the element to be replaced with. There are other cumbersome ways to do this by iterating through ArrayList and removing etc, but here i will use another easy way to remove repeated values in ArrayList…. These streams support all the types of objects, data-types, characters, files, etc to fully execute the I/O operations. To get an element from ArrayList in Java, call get () method on this ArrayList. Do you want to identify duplicates elements from Java List? The method add of set returns a boolean whether a value already exists (true if it . Contains() when populating the list to ensure the duplicates …. Each Provider will have 2 addresses. How do I remove duplicates from an arraylist? Nov 21 '05 #8. Vector is the name of a class that is present in java. So for example, in an ArrayList of strings which contains cat, cat, dog, horse, zebra, zebra, the answer should be two. String array or integer array or array of any object. Update: The Datumbox Machine Learning Framework is now open-source and free to download. Why we choose LinkedHashSet? Because it removes duplicates and maintains the insertion order. By using this method we can find both duplicate and unique elements from two lists. So just iterate through all the values. In this post, I will show you how to find duplicate objects in a List using Java's Comparator interface implementation based on multiple fields in a POJO. Then we could use the iterator function. arraylist java find duplicates. There are many techniques to find duplicate elements in array in java like using Collections. The example explains the process of creating a 2-dimensional array list and then adding a value to the array list and then the value is attempted to be replaced with a different value. How to remove duplicate values from ArrayList using SetUniqueList? apache common-collection API provides org. How do I count the duplicate objects in ArrayList in Java?. arraylist is one of the collection class of collection framework. ) First Iteration of array: index = 0; Math. To get a value from ArrayList in Java, call get method. It can help you in to find most frequent words or count repeated words in a string. Convert the list into ‘stream’. In the first solution, we compare each element of the array to every other element. List; /** * Remove Duplicates from a List Using Java * @author Ramesh Fadatare * */ public class FindDuplicatesInList { public static void main (String [] args) { List < Integer > listWithDuplicates = Arrays.