Avoid possible NPE (it really needs to throw a rejected execution instead anyway).

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1574162 13f79535-47bb-0310-9956-ffa450edef68
Fix wrong booleans (which shouldn't change anything in practice, but the code is wrong).

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1574163 13f79535-47bb-0310-9956-ffa450edef68
Avoid possible NPE.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1574167 13f79535-47bb-0310-9956-ffa450edef68