91. 91
String#split()
“When there is a positive-width match at the beginning of this string
then an empty leading substring is included at the beginning of the
resulting array. A zero-width match at the beginning however never
produces such empty leading substring.”
英語版Java SE8ドキュメントより引用
http://docs.oracle.com/javase/8/docs/api/java/lang/String.html