Java thread state transition, WAITING to BLOCKED, or RUNNABLE?

Any diagram that shows a notify invocation bringing a thread from WAITING to RUNNABLE is wrong (or is using an unclarified shortcut). Once a thread gets awoken from a notify (or even from a spurious wakeup) it needs to relock the monitor of the object on which it was waiting. This is the BLOCKED state.

Thread state for a thread blocked waiting for a monitor lock. A thread
in the blocked state is waiting for a monitor lock to enter a
synchronized block/method or reenter a synchronized block/method after
calling Object.wait.

This is explained in the javadoc of Object#notify():

The awakened thread will not be able to proceed until the current
thread relinquishes the lock on this object.

and Object#wait()

The thread then waits until it can re-obtain ownership of the monitor
and resumes execution.