This is the description of the documentation of ConcurrentLinkedQueue:
An unbounded thread-safe queue based on linked nodes. This queue orders elements FIFO (first-in-first-out).
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This implementation employs an efficient “wait-free” algorithm
Is it possible to be unbounded and wait-free?
I am pretty sure wait-freedom ensures a bound on any operation.
A bound on the time (or number of instructions, or whatever) taken by the operation.
In that JavaDoc, "Unbounded" probably refers to the number of elements the queue may contain.
For instance, the JavaDoc for LinkedBlockingDeque writes: