Java Utililty Methods Collection First

List of utility methods to do Collection First

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Description

The list of methods to do Collection First are organized into topic(s).

Method

Tfirst(Collection c)
first 
return c.iterator().next();
Tfirst(Collection collection)
Return the first element of the collection. 
if (collection.isEmpty()) {
    return null;
return collection.iterator().next();
Tfirst(Collection collection)
Replaces first() LINQ Returns first object of collection or null if empty 
Iterator<T> iterator = collection.iterator();
if (iterator.hasNext())
    return iterator.next();
else
    return null;
ObjectfirstElement(Collection in)
return the first element in a collection - this is most useful where only one item exists in the collection 
if (in.size() == 0)
    throw new IllegalArgumentException("firstElement requies at least one entry");
return (in.iterator().next());
TfirstElement(Collection c)
first Element 
if (c != null && !c.isEmpty()) {
    return c.iterator().next();
return null;
TfirstElementOf(final Collection collection)
Returns the first element of the given collection 
if (isEmpty(collection)) {
    return null;
return collection.iterator().next();
TfirstElementOf(final Collection items)
first Element Of 
if (items != null && !items.isEmpty()) {
    return items.iterator().next();
return null;
ObjectfirstFrom(Collection collection)
first From 
return collection.iterator().next();
TfirstFrom(Collection coll)
first From 
if (isEmpty(coll))
    return null;
return coll.iterator().next();
CollectionfirstNonEmpty(Collection... collections)
first Non Empty 
for (Collection<T> collection : collections)
    if (!isEmpty(collection))
        return collection;
return emptySet();