Apache Shiro
Copyright 2008-2020 The Apache Software Foundation

This product includes software developed at
The Apache Software Foundation (http://www.apache.org/).

The implementation for org.apache.shiro.util.SoftHashMap is based 
on initial ideas from Dr. Heinz Kabutz's publicly posted version 
available at http://www.javaspecialists.eu/archive/Issue015.html,
with continued modifications.  

Certain parts (StringUtils, IpAddressMatcher, etc.) of the source
code for this  product was copied for simplicity and to reduce
dependencies  from the source code developed by the Spring Framework
Project  (http://www.springframework.org).