Java Collection First firstElement(Collection in)

Description

return the first element in a collection - this is most useful where only one item exists in the collection

License

Apache License

Parameter

Parameter	Description
in	non-null collection with at least one value

Exception

Parameter	Description
IllegalArgumentException	of the collection is empty

Return

non-null object

Declaration

public static Object firstElement(Collection in) 

Method Source Code

//package com.java2s;
//License from project: Apache License 

import java.util.*;

public class Main {
    /**//from   w  w w .j  av a  2 s.  c  om
     * return the first element in a collection - this is most useful where only one item
     * exists in the collection
     * @param in non-null collection with at least one value
     * @return non-null object
     * @throws IllegalArgumentException of the collection is empty
     */
    public static Object firstElement(Collection in) {
        if (in.size() == 0)
            throw new IllegalArgumentException("firstElement requies at least one entry");
        return (in.iterator().next());
    }
}

Related

1. first(Collection self)
2. first(Collection c)
3. first(Collection c)
4. first(Collection collection)
5. first(Collection collection)
6. firstElement(Collection c)
7. firstElementOf(final Collection collection)
8. firstElementOf(final Collection items)
9. firstFrom(Collection collection)