Let’s learn how to remove duplicates from arraylist in java. How to remove duplicates from ArrayList in java Here the task is to remove duplicates in ArrayList. In the below java program first get given ArrayList with duplicate integer values. Now print ArrayList with duplicate integer values on the console. Create another ArrayList ‘alNew’. Pass…
Read More How to remove duplicates from ArrayList in javaLet’s learn how to remove duplicates from array in java without using collections. How to remove duplicates from array in java without using collections To remove duplicates from array is bit tricky. Because problem with arrays is not finding duplicates, its about removing duplicates. We all know that an array is a static data structure…
Read More How to remove duplicates from array in java without using collectionsLet’s learn difference between while and do while loop in java. Difference between while and do while loop in java While loop do while loop In while loop condition is checked first and then statements are executed. In do while loop statements are executed atleast once and then condition is checked. In while loop statements…
Read More Difference between while and do while loop in javaLet’s learn do while loop with user input in java. Do while loop with user input in java Now let’s learn to add user input numbers and get total using do while loop. In the below program if user inputs 0, do while loop terminates the loop and finally prints the total of user input…
Read More Do while loop with user input in javaLet’s learn how to remove last element from arraylist in java. How to remove last element from ArrayList in java To remove last element from arraylist use two overloaded remove() method of ArrayList. They are, Here’s an example on remove(int index) to last element from arraylist. import java.util.ArrayList; import java.util.List; public class ArrayListRemoveLastElement { public…
Read More How to remove last element from ArrayList in javaLet’s learn to create dynamic 2D array in java. Create dynamic 2D array in java Dynamic two dimensional array is one array where user can add and remove rows and columns on need and can have varying number of rows and columns. To implement dynamic two dimensional array we use a combination of List(can shrink…
Read More Create Dynamic 2D array in javaLet’s learn how to sort ArrayList in java. How to sort ArrayList in java In java, ArrayList does not follow sorting order. So to sort an ArrayList we are using Collections class sort() method which sorts in ascending order and sorting arraylist in descending order using Comparator interface. Collections.sort() method – Sorts the specified list…
Read More How to sort ArrayList in javaLet’s learn how to sort TreeSet in descending order in java. How to sort TreeSet in descending order in java In this post lets sort TreeSet elements in descending order or decreasing order. For this we are using descendingSet() method. This method returns a reverse order view of the elements contained in this set. import…
Read More How to sort TreeSet in descending order in javaLet’s learn TreeMap sort by values in java. TreeMap sort by values in java TreeMap stores key-value pairs which are in sorted order based on key. To sort a treemap by value we have to build some logic using comparator class. Here’s an example on how to sort a treemap by value. import java.util.Comparator; import…
Read More TreeMap sort by values in javaLet’s learn TreeMap comparator() method in java with examples. Treemap comparator() method in java with examples TreeMap comparator() method returns the comparator used to order the keys in this map, or null if this map uses the natural ordering of its keys. Let’s see example on TreeMap comparator() method for natural ordering. import java.util.Comparator; import…
Read More TreeMap comparator() method in java with examples