solr.ManagedSynonymFilterFactory/ManagedStopwordFilterFactory: URLEncoding - Not able to delete Synonyms/Stopwords with special characters

Hi Guys,

We're using the SOLR Rest API in order to manage synonyms and stopwords with solr.Managed*FilterFactory.

{emphasis}The same applies to stopwords. I am going to explain the synonym case only from this point on.{emphasis}
Let us consider the following _schema_analysis_synonyms_en.json managedMap: {
"xxx#xxx":"xxx#xxx",
"xxx%xxx":["xxx%xxx"],
"xxx/xxx":["xxx/xxx"],
"xxx:xxx":["xxx:xxx"],
"xxx;xxx":["xxx;xxx"],
"xxxxxx ":["xxxxxx "]
}

I can add such synonym to keyword relations using REST API. The problem is that I cannot remove/list them as http://localhost:8983/solr/collection1/schema/analysis/synonyms/en/<entryname> where <entryname> is one of the map's key throws 404, or 500 (in case of xxx%25xxx):
java.lang.NullPointerException at org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:367) at org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:207) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1419) at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:455) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:137) at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:557) at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:231) at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1075) at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:384) at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:193) at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1009) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:135) at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:255) at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:154) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:116) at org.eclipse.jetty.server.Server.handle(Server.java:368) at org.eclipse.jetty.server.AbstractHttpConnection.handleRequest(AbstractHttpConnection.java:489) at org.eclipse.jetty.server.BlockingHttpConnection.handleRequest(BlockingHttpConnection.java:53) at org.eclipse.jetty.server.AbstractHttpConnection.headerComplete(AbstractHttpConnection.java:942) at org.eclipse.jetty.server.AbstractHttpConnection$RequestHandler.headerComplete(AbstractHttpConnection.java:1004) at org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:640) at org.eclipse.jetty.http.HttpParser.parseAvailable(HttpParser.java:235) at org.eclipse.jetty.server.BlockingHttpConnection.handle(BlockingHttpConnection.java:72) at org.eclipse.jetty.server.bio.SocketConnector$ConnectorEndPoint.run(SocketConnector.java:264) at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:608) at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:543) at java.lang.Thread.run(Unknown Source)