in src/main/java/org/apache/commons/io/FilenameUtils.java [305:328]
private static String doGetFullPath(final String fileName, final boolean includeSeparator) {
if (fileName == null) {
return null;
}
final int prefix = getPrefixLength(fileName);
if (prefix < 0) {
return null;
}
if (prefix >= fileName.length()) {
if (includeSeparator) {
return getPrefix(fileName); // add end slash if necessary
}
return fileName;
}
final int index = indexOfLastSeparator(fileName);
if (index < 0) {
return fileName.substring(0, prefix);
}
int end = index + (includeSeparator ? 1 : 0);
if (end == 0) {
end++;
}
return fileName.substring(0, end);
}