In class com.opensymphony.oscache.base.Cache, two bad practice i think can be seen. One the use of e.printStackTrace(), is commanly know that this is a bad practice. The other bad practice is making a try/catch with Exception. In the same line, inside try/catch there is a throws new Exception() and is catched inside it.

try {
    throw new Exception("states not equal");
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

You can see above all bad practices.