Fixed StringIndexOutOfBoundsException when trying to get the first char of an empty string. String.substring methods always return an object. Based on a patch provided by wuwen via Github.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/tc7.0.x/trunk@1758590 13f79535-47bb-0310-9956-ffa450edef68
2 files changed