== Why is this an issue? When two locks are held simultaneously, a ``++wait++`` call only releases one of them. The other will be held until some other thread requests a lock on the awaited object. If no unrelated code tries to lock on that object, then all other threads will be locked out, resulting in a deadlock. === Noncompliant code example [source,java] ---- synchronized (this.mon1) { // threadB can't enter this block to request this.mon2 lock & release threadA synchronized (this.mon2) { this.mon2.wait(); // Noncompliant; threadA is stuck here holding lock on this.mon1 } } ---- ifdef::env-github,rspecator-view[] ''' == Implementation Specification (visible only on this page) === Message Don't use "wait()" here; multiple locks are held. ''' == Comments And Links (visible only on this page) include::../comments-and-links.adoc[] endif::env-github,rspecator-view[]