Collection.add

Ensures that this collection contains the specified element (optional operation). Returns <tt>true</tt> if this collection changed as a result of the call. (Returns <tt>false</tt> if this collection does not permit duplicates and already contains the specified element.)<p>

Collections that support this operation may place limitations on what elements may be added to this collection. In particular, some collections will refuse to add <tt>null</tt> elements, and others will impose restrictions on the type of elements that may be added. Collection classes should clearly specify in their documentation any restrictions on what elements may be added.<p>

If a collection refuses to add a particular element for any reason other than that it already contains the element, it <i>must</i> throw an exception (rather than returning <tt>false</tt>). This preserves the invariant that a collection always contains the specified element after this call returns.

@param e element whose presence in this collection is to be ensured @return <tt>true</tt> if this collection changed as a result of the call @throws UnsupportedOperationException if the <tt>add</tt> operation is not supported by this collection @throws ClassCastException if the class of the specified element prevents it from being added to this collection @throws NullPointerException if the specified element is null and this collection does not permit null elements @throws IllegalArgumentException if some property of the element prevents it from being added to this collection @throws IllegalStateException if the element cannot be added at this time due to insertion restrictions

interface Collection(E)
bool
add
(
E e
)

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