/usr/share/doc/libservlet2.5-java-doc/api is in libservlet2.5-java-doc 6.0.45+dfsg-1~deb8u1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libservlet2.5-java-doc/../libservlet2.5-java/api