offer
Inserts the specified element into this queue if it is possible to do so immediately without violating capacity restrictions. When using a capacity-restricted queue, this method is generally preferable to .add, which can fail to insert an element only by throwing an exception.
Return
true if the element was added to this queue, else false
Parameters
e
the element to add
Throws
if the class of the specified element prevents it from being added to this queue
if the specified element is null and this queue does not permit null elements
if some property of this element prevents it from being added to this queue