Example usage for java.util Collection add

Introduction

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

Prototype

boolean add(E e);

Source Link

Document

Ensures that this collection contains the specified element (optional operation).

Usage

From source file:Main.java

public static <E> Collection<E> List2Collection(List<E> elements) {
    if (elements == null || elements.size() <= 0) {
        return null;
    }//  w w w  .j a  v a 2  s  .c o  m
    Collection<E> collections = elements;
    for (E e : elements) {
        collections.add(e);
    }

    return collections;
}

From source file:Main.java

public static <K, V> Map<K, Collection<V>> toMap(final Collection<? extends V> items,
        final Function<V, K> mapper) {
    Map<K, Collection<V>> buffer = new HashMap<K, Collection<V>>();
    // TODO this isn't probably thread-safe
    items.stream().forEach(item -> {/* w  ww. ja va 2  s  .  c  o m*/
        K key = mapper.apply(item);
        Collection<V> c = buffer.getOrDefault(key, new ArrayList<V>());
        c.add(item);
        buffer.put(key, c);
    });
    return buffer;
}

From source file:Main.java

/**
 * Copy Iterable content to a list. /*from w ww  . ja  v  a  2s  . c o m*/
 * @param iter : Iterable 
 * @return
 */
public static <E> Collection<E> makeCollection(Iterable<E> iter) {
    Collection<E> list = new LinkedList<E>();
    for (E item : iter) {
        list.add(item);
    }
    return list;
}

From source file:Main.java

/**
 *  Adds a value to the collection if the boolean expression is true.
 *  Returns the collection as a convenience for chained invocations.
 *
 *  @since 1.0.8//w ww.j  ava  2  s.c  o m
 */
public static <T> Collection<T> addIf(Collection<T> coll, T value, boolean expr) {
    if (expr)
        coll.add(value);

    return coll;
}

From source file:Main.java

public static <T> void addAll(Collection<T> target, Iterable<? extends T> source) {
    for (T e : source)
        target.add(e);
}

From source file:Main.java

public static void arrayToCollection(Collection c, Object[] array) {
    for (int i = 0; i < array.length; i++)
        c.add(array[i]);
}

From source file:Main.java

/**
 * @param element/*from   w ww. j a  v  a 2s .  c o m*/
 * @param collection
 */
public static <O> void addIfNotNull(final O element, final Collection<O> collection) {
    if (element != null) {
        collection.add(element);
    }
}

From source file:Main.java

public static void addAll(final Collection<Integer> coll, final int... values) {
    for (final int i : values)
        coll.add(i);
}

From source file:Main.java

public static <T> void addAll(Collection<T> collection, T... array) {
    for (T t : array) {
        collection.add(t);
    }/*from  w  w  w.  ja  va 2  s.co m*/
}

From source file:Main.java

public static <T> void addAll(Collection<T> collection, T[] array) {
    for (int i = 0; i < array.length; ++i)
        collection.add(array[i]);
}