PDFBOX-1897: fix javadoc error

git-svn-id: https://svn.apache.org/repos/asf/pdfbox/branches/1.8@1588481 13f79535-47bb-0310-9956-ffa450edef68
PDFBOX-1897: fix javadoc error

git-svn-id: https://svn.apache.org/repos/asf/pdfbox/branches/1.8@1588482 13f79535-47bb-0310-9956-ffa450edef68