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#Java - Code Snippets for '#Lists' - 31 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. 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 3. 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 4. 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


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 Sample 5. 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 6. 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 7. 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 8. 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 9. 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


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 Sample 10. 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 11. 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 12. 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 13. 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 14. 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


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 Sample 15. 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 16. 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 17. 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 18. 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 19. 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


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 Sample 20. 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 21. 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 22. 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 23. 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 24. 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


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 Sample 25. 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 26. 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 27. 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 28. 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 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


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 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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