Stale value of Shared variable

Question

While reading Concurrency in practice I read that:

NoVisibility demonstrated one of the ways that insufficiently synchronized programs can c

Answer 1

It's saying that in main the intention is to set number=42 and ready=true at the same time, but since they were called in this particular order there is a race condition with your ReaderThread where it could (probably will) print out the number even though we really don't want it to.

They would like you to synchronize those 2 variables to be set together.