#Java - Code Snippets for '#Arraylist'

#Java - Code Snippets for '#Arraylist' - 10 code snippet(s) found

Sample 1. Usage of Apache Commons - ArrayListValuedHashMap

ListValuedMap<String,String> listValuedMap = new ArrayListValuedHashMap();

listValuedMap.put("United States", "Washington");

listValuedMap.put("Canada", "Ottawa");

listValuedMap.put("Canada", "Ottawa");

listValuedMap.put("South Africa", "Pretoria");

listValuedMap.put("South Africa", "Cape Town");

listValuedMap.put("South Africa", "Bloemfontein");



System.out.println(listValuedMap); // Values being added to the List and allow even duplicates

_{Like Feedback apache commons apache commons collections ArrayListValuedHashMap ListValuedMap}

Sample 2. Get all Permutations of List Elements using Apache Commons PermutationIterator

List<String> list = new ArrayList();

list.add("Washington");

list.add("Nevada");

list.add("California");



PermutationIterator permIterator = new PermutationIterator((Collection) list);

        

permIterator.forEachRemaining(System.out::print); // prints [Washington, Nevada, California][Washington, California, Nevada][California, Washington, Nevada][California, Nevada, Washington][Nevada, California, Washington][Nevada, Washington, California]

_{Like Feedback Permutations of collection elements Permutations of List elements Apache Commons PermutationIterator Iterator Collections .forEachRemaining System.out::print List ArrayList}

Sample 3. Sorting an arraylist using Collections.sort

List<String> myList = new ArrayList<String>();

myList.add("D");

myList.add("A");

myList.add("B");

myList.add("C");

myList.add("E");



System.out.println(myList); // Unsorted



Collections.sort(myList);



System.out.println(myList); // Sorted

_{Like Feedback list arraylist collections.sort collections}

Sample 4. Looping through elements of an ArrayList

public static void main(String[] args){

      List list = new ArrayList();

      list.add(1);

      list.add(2);

      list.add(3);

      for(Integer element: list){

         System.out.println(element);

      }

   }

_{Like Feedback arraylist list collections}

Sample 5. Display Elements of a List using Java 8 Consumer

List myList = new ArrayList();

      

myList.add("A");

myList.add("B");

myList.add("C");



myList.forEach(System.out::println);

_{Like Feedback Print elements of a list java 8 consumer foreach list arraylist collections}

Sample 6. ArrayList of Optional Integers

List<Optional<Integer>> intList = new ArrayList<Optional<Integer>>();



// Add Elements



intList.add(Optional.empty());

intList.add(Optional.of(2));

intList.add(Optional.of(3));

intList.add(Optional.of(4));

_{Like Feedback optional java 8 list arraylist list of optional integers arraylist of optional java.util.Optional}

Sample 7. Initialize list using google guava Lists

import java.util.List;

import com.google.common.collect.Lists;



class GoogleListsTest{

   public static void main(String[] args){

      List list = Lists.newArrayList();

   }

}

_{Like Feedback list google guava Lists Lists.newArrayList com.google.common.collect.Lists}

Sample 8. Internal Implementation of ArrayList#removeIf

@Override

    public boolean removeIf(Predicate<? super E> filter) {

        Objects.requireNonNull(filter);

 

        int removeCount = 0;

        final BitSet removeSet = new BitSet(size);

        final int expectedModCount = modCount;

        final int size = this.size;

        for (int i=0; modCount == expectedModCount && i < size; i++) {

            @SuppressWarnings("unchecked")

            final E element = (E) elementData[i];

            if (filter.test(element)) {

                removeSet.set(i);

                removeCount++;

            }

        }

        if (modCount != expectedModCount) {

            throw new ConcurrentModificationException();

        }



        // shift surviving elements left over the spaces left by removed elements

        final boolean anyToRemove = removeCount > 0;

        if (anyToRemove) {

            final int newSize = size - removeCount;

            for (int i=0, j=0; (i < size) && (j < newSize); i++, j++) {

                i = removeSet.nextClearBit(i);

                elementData[j] = elementData[i];

            }

            for (int k=newSize; k < size; k++) {

                elementData[k] = null;  // Let gc do its work

            }

            this.size = newSize;

            if (modCount != expectedModCount) {

                throw new ConcurrentModificationException();

            }

            modCount++;

        }



        return anyToRemove;

    }

_{Like Feedback Internal Implementation of ArrayList#removeIf java.util.function.Predicate java.util.Objects java.util.Objects java.util.ConcurrentModificationException.ConcurrentModificationException}

Sample 9. Display elements of a List using For loop

List myList = new ArrayList();

      

myList.add("A");

myList.add("B");

myList.add("C");



for(String str:myList){  // prints A B C

   System.out.println(str);

}

_{Like Feedback Print elements of a list for loop arraylist list collections}

Sample 10. Display elements of a List using For Loop and index

List myList = new ArrayList();

      

myList.add("A");

myList.add("B");

myList.add("C");



for(int index=0;index < myList.size(); index++){

   System.out.println(myList.get(index));

}

_{Like Feedback Print elements of a list arraylist list collections for loop}

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