Example usage for java.util Collection addAll

Introduction

In this page you can find the example usage for java.util Collection addAll.

Prototype

boolean addAll(Collection<? extends E> c);

Source Link

Document

Adds all of the elements in the specified collection to this collection (optional operation).

Usage

From source file:Main.java

static <V> void addAllIfNotNull(final Collection<V> collection, final Collection<V> values) {
    if (collection != null && values != null) {
        collection.addAll(values);
    }/*from  w  w  w.ja  v  a 2 s. co m*/

}

From source file:Main.java

public static <T> void addIfNotEmpty(Collection<T> c, Collection<T> elements) {
    if (null != c && null != elements && !elements.isEmpty()) {
        c.addAll(elements);
    }/* w  ww  . j a  v  a 2s.c om*/
}

From source file:Main.java

public static <T> Collection<T> flatten(final Collection<? extends Collection<T>> second) {
    final Collection<T> returnList = new ArrayList<>();

    for (final Collection<T> collection : second) {
        returnList.addAll(collection);
    }/*ww  w .j av  a 2s  . c  o m*/

    return returnList;
}

From source file:Main.java

public static <E> void intersection(final Collection<E> a, final Collection<E> b) {
    if (b != null && !b.isEmpty()) {
        if (a.isEmpty()) {
            a.addAll(b);
        } else {// ww  w .  jav a  2 s .  c om
            a.retainAll(b);
        }
    }
}

From source file:Main.java

/**
 * Adds all of the elements in the specified collection to the target collection if
 * a collection is specified.//from   w ww  .  j  a  v a  2  s.  c  om
 * 
 * @param <E>
 * @param target
 * @param c collection containing elements to be added to this collection, may be null
 * @return <tt>true</tt> if this collection changed as a result of the call
 */
public static <E> boolean addAllIfSet(Collection<E> target, Collection<? extends E> c) {
    if (c == null)
        return false;
    return target.addAll(c);
}

From source file:Main.java

@SuppressWarnings("unchecked")
public static <T> Collection<T> unique(Collection<T> c, Collection<T> result) {
    if (c == null) {
        return result;
    }/*from ww w.  j a  va2 s  .co  m*/
    Set<T> s = new LinkedHashSet<T>(c);
    result.addAll(s);
    return result;
}

From source file:Main.java

public static <T> Collection<T> merge(Collection<T>... col) {

    //ensure maximum capacity
    Collection<T> result = new ArrayList(col.length);

    for (Collection<T> c : col) {
        if (c != null)
            result.addAll(c);
    }/*  w w w . ja v  a 2  s .co  m*/

    return result;

}

From source file:Main.java

/**
 * /*from  ww w .  j ava 2s .  co  m*/
 * @param collections
 * @return Collection
 */
public static Collection<?> getIntersection(
        final Collection<? extends Collection<? extends Object>> collections) {
    final List<Collection<?>> collectionsList = new ArrayList<Collection<?>>(collections);
    final Collection<Object> intersection = new HashSet<>();

    if (collectionsList.size() != 0) {
        intersection.addAll(collectionsList.get(0));
    }

    for (int i = 1; i < collections.size() && intersection.size() > 0; i++) {
        intersection.retainAll(new HashSet<>(collectionsList.get(i)));
    }

    return intersection;
}

From source file:Main.java

/**
 * Adds the given items to the given collection
 * /*from  w w w.j  av  a  2 s. com*/
 * @param <T>
 *            the type of item in the collection being updated
 * @param newItems
 *            the items being added; can be <code>null</code> for none
 * @param existingItems
 *            the items being added to; must be modifiable
 * @return <code>true</code> if the existing collection was modified
 * @throws UnsupportedOperationException
 *             if there are items to add and the existing collection is not
 *             modifiable
 * @since 1.2.0
 */
public static <T> boolean addAll(final Collection<? extends T> newItems, final Collection<T> existingItems) {
    if ((existingItems != null) && (newItems != null)) {
        return existingItems.addAll(newItems);
    }
    return false;
}

From source file:Main.java

public static <K> void addAll(Collection<K> destination, Collection<? extends K> toBeAdded) {
    if (destination != null && toBeAdded != null) {
        destination.addAll(toBeAdded);
    }/*from  ww  w .j ava  2s.co  m*/
}