#Java - Code Snippets for '#List'

#Java - Code Snippets for '#List' - 31 code snippet(s) found

Sample 1. Given a Map with Country Name as key and its capitals as values, Find the name of countries having more than 1 capital ?

Map<String,List<String>> capitals = new HashMap();

capitals.put("United States", Arrays.asList("Washington DC"));

capitals.put("Canada", Arrays.asList("Ottawa"));

capitals.put("South Africa", Arrays.asList("Pretoria", "Cape Down", "Bloemfontein"));

      

for(Map.Entry<String,List<String>> entry: capitals.entrySet()){

   if(entry.getValue().size() > 1){

      System.out.println(entry.getKey());

   }

}

_{Like Feedback Map of String and List}

Sample 2. 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 3. 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 4. Method to remove duplicates from a Map ( string and List of objects ) by matching the member field of the object.

Map<String,List<ClassInfoBean>> removeDuplicates(Map<String, List<ClassInfoBean>> interfaceMap){

   Map<String, List<ClassInfoBean>> interfaceMapWithoutDuplicate = new HashMap();

      

   for(Map.Entry<String, List<ClassInfoBean>> entry: interfaceMap.entrySet()){

      List<ClassInfoBean> classListWithoutDuplicate = new ArrayList();

      boolean alreadyContain = false;

      for(ClassInfoBean classes: entry.getValue()){

         for(ClassInfoBean classes1: classListWithoutDuplicate){

            if(classes1.name.equalsIgnoreCase(classes.name)){

               alreadyContain = true;

               break;

            }

         }

         if(alreadyContain == false){

            classListWithoutDuplicate.add(classes);

         }

      }

      interfaceMapWithoutDuplicate.put(entry.getKey(), classListWithoutDuplicate);

   }

      

   return interfaceMapWithoutDuplicate;

}

_{Like Feedback map map of list of objects remove duplicates from map Map.Entry}

Sample 5. Populate a List using Set elements and Lambda Expression

// Declare and Initialize the Collection



Set<Integer> intSet = new HashSet<Integer>();



// Add Elements



intSet.add(1);

intSet.add(2);

intSet.add(3);

intSet.add(4);



// Use the stream and collectors to get List out of Set



List li = intSet.stream().collect(Collectors.toList());

System.out.println(li); // Prints [1, 2, 3, 4]

_{Like Feedback lambda expression collections set hashset generics stream collectors Collectors.toList}

Sample 6. Enum with a method to get the constant having specific member element.

public enum JavaFramework {

   SPRING("Spring","Web"),

   STRUTS("Struts","Web"),

   JSF("JSF","View"),

   CRUNCH("Apache Crunch","BigData");

   

        

   public String name;

   public String type;



   JavaFramework(String name, String type){

      this.name = name;

      this.type = type;

   }

   

   static public List<JavaFramework> getByType(String type)  {

      List<JavaFramework> frameworks = new ArrayList();

      for(JavaFramework framework: JavaFramework.values()){

         if(framework.type.equalsIgnoreCase(type)){

            frameworks.add(framework);

         }

      }

      

      return frameworks;

   }

}

_{Like Feedback enum java.util.list}

Sample 7. 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 8. 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 9. 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 10. Get the Maximum number out of the Integer List, using Lambda Expression

// Declare and Initialize the Collection



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



// Add Elements



intList.add(1);

intList.add(2);

intList.add(3);

intList.add(4);





System.out.println(intList.stream().reduce(Math::max).get()); // Prints 1

_{Like Feedback lambda expression collections set hashset generics stream reducer Math::max}

Sample 11. ajax / Jquery call to get the list of check boxes to be disabled.

function disableCheckBox(){

    sendAjaxGetCall(“/resourceUrl?input=”+input) .done(function(data) {

          data = data + '';

          var checkboxToDisable = data.split(",");

          for(int i=0;i < checkboxToDisable.length;i++){

                $(“#”+i).attr("disabled", true);

           }

     }).fail(function(xhr, error) {

           console.log('error: ' + xhr.statusText);

     });

}

_{Like Feedback jquery ajax checkbox disable checkbox}

Sample 12. Method to remove duplicates from a List of objects by matching the member elements of objects.

List<ClassInfoBean> removeDuplicates(List<ClassInfoBean> listClassInfo){

   Set<ClassInfoBean> set = new HashSet();

   Set<String> url = new HashSet();

   boolean flag = false;

   for(ClassInfoBean cl: listClassInfo){

      if(!url.contains(cl.url)){

         set.add(cl);

         url.add(cl.url);

      }

   }

      

   return new ArrayList(set);

}

_{Like Feedback list list of objects remove duplicates from list}

Sample 13. Sort a List using Collections.sort and comparator

Collections.sort(listClassInfo,new Comparator<ClassInfoBean>(){

            public int compare(ClassInfoBean s1,ClassInfoBean s2){

                  if(s1.name.compareTo(s2.name) < 0){

                     return -1;

                  } else {

                     return 1;

                  }

                  

}});

_{Like Feedback sorting sort Collections.sort sort a list comparator compare method java.util.Collections}

Sample 14. 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 15. 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 16. Method to get specific format files from a directory

private Collection<File> getDocAndTextFiles() {

    File directory = new File("C:DocDir");

    if (directory.exists() && directory.isDirectory()) {

      Collection<File> files = FileUtils.listFiles(directory, new String[] { "doc","txt" }, false);

    }

    return files;

}

_{Like Feedback file handling file directory FileUtils.listFiles fileutils}

Sample 17. 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 18. Check whether a reference of AbstractCollection holds a List,Queue or Set

public static void main(String[] args)  {

        

        AbstractCollection collection = new ArrayList();

        

        if(collection instanceof AbstractList){

           System.out.println("This is a list");

        }

        

        if(collection instanceof AbstractQueue){

           System.out.println("This is a Queue");

        }

        

        if(collection instanceof AbstractSet){

           System.out.println("This is a Set");

        }

          

}

_{Like Feedback instaceOf AbstractCollection}

Sample 19. Print all elements of a ListValuedMap ( Apache Commons ) using forEach and System.out::println

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");



listValuedMap.entries().forEach(System.out::println);

_{Like Feedback ListValuedMap apache commons System.out::println collections framework map}

Sample 20. Usage of ConcurrentSkipListMap

Map<String,String> map = new ConcurrentSkipListMap();

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

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

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

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

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

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



System.out.println(map); // Prints {Canada=Ottawa, South Africa=Bloemfontein, United States=Washington}

        

// Duplicates not allowed as it's a Map, Sorted as par natural order of keys for faster and concurrent operations.

_{Like Feedback map ConcurrentSkipListMap concurrent access map}

Sample 21. Usage of SslListener

SslListener sslListener = new SslListener();

sslListener.setHost(addr.getHostName());

sslListener.setPort(addr.getPort());

sslListener.setKeystore(keystore);

sslListener.setPassword(storPass);

sslListener.setKeyPassword(keyPass);

webServer.addListener(sslListener);

_{Like Feedback SslListener}

Sample 22. Code Sample / Example / Snippet of java.util.EventListener

    private void readObject(ObjectInputStream s)

        throws IOException, ClassNotFoundException {

        listenerList = NULL_ARRAY;

        s.defaultReadObject();

        Object listenerTypeOrNull;



        while (null != (listenerTypeOrNull = s.readObject())) {

            ClassLoader cl = Thread.currentThread().getContextClassLoader();

            EventListener l = (EventListener)s.readObject();

            String name = (String) listenerTypeOrNull;

            ReflectUtil.checkPackageAccess(name);

            add((Class<EventListener>)Class.forName(name, true, cl), l);

        }

    }

_{Like Feedback java.util.EventListener}

Sample 23. Code Sample / Example / Snippet of org.apache.spark.network.shuffle.BlockFetchingListener

  public void testNoFailures() throws IOException {

    BlockFetchingListener listener = mock(BlockFetchingListener.class);



    List<? extends Map<String, Object>> interactions = Arrays.asList(

      ImmutableMap.<String, Object>builder()

        .put("b0", block0)

        .put("b1", block1)

        .build()

      );



    performInteractions(interactions, listener);



    verify(listener).onBlockFetchSuccess("b0", block0);

    verify(listener).onBlockFetchSuccess("b1", block1);

    verifyNoMoreInteractions(listener);

  }

_{Like Feedback org.apache.spark.network.shuffle.BlockFetchingListener}

Sample 24. Code Sample / Example / Snippet of java.util.List

    private static List convertArrayToList(Object array)

    {

        int len = Array.getLength(array);

        List list = new ArrayList(len);

        for (int i = 0; i < len; i++)

        {

            list.add(Array.get(array, i));

        }

        return list;

    }

_{Like Feedback java.util.List}

Sample 25. Code Sample / Example / Snippet of org.apache.bcel.generic.InstructionList

    private void compare(final String name, final Method m) {

        final Code c = m.getCode();

        if (c == null) {

            return; // e.g. abstract method

        }

        final byte[] src = c.getCode();

        final InstructionList il = new InstructionList(src);

        final byte[] out = il.getByteCode();

        if (src.length == out.length) {

            assertArrayEquals(name + ": " + m.toString(), src, out);

        } else {

            System.out.println(name + ": " + m.toString() + " " + src.length + " " + out.length);

            System.out.println(bytesToHex(src));

            System.out.println(bytesToHex(out));

            for (final InstructionHandle ih : il) {

                System.out.println(ih.toString(false));

            }

            fail("Array comparison failure");

        }

    }

_{Like Feedback org.apache.bcel.generic.InstructionList}

Sample 26. Display Elements of a List

List myList = new ArrayList();

      

myList.add("A");

myList.add("B");

myList.add("C");



System.out.println(myList); // Prints [A, B, C]

_{Like Feedback Print elements of a list}

Sample 27. 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 28. 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}

Sample 29. Given a list of File objects, sort them by their name

public List sortFiles(List<File> files) {

    files.sort(new Comparator<File>() {

      @Override

      public int compare(File file1, File file2) {

        return file1.getName().compareTo(file2.getName());

      }

    });



    return files.

 }

_{Like Feedback file}

Sample 30. Code to get Module name for List class

Module module = java.util.List.class.getModule();

System.out.println(module.getName()); // prints java.base

_{Like Feedback java 9 java 9 module}

Sample 31. Initializing a list using factory method in java 9

Usage of List.of()

List<String> countryList = List.of("France","Belgium","Germany");

_{Like Feedback java 9}

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