NSD file referred by DependsOn may not be present
In NSDImpl.java, findXXX() use refersToNS() provided by DependsOn without checking that it is present (the file containing the requested NS may not be loaded), thus NPE.
In NSDImpl.java, findXXX() use refersToNS() provided by DependsOn without checking that it is present (the file containing the requested NS may not be loaded), thus NPE.