Github user necouchman commented on a diff in the pull request:
https://github.com/apache/guacamole-client/pull/291#discussion_r191626044
--- Diff:
guacamole/src/main/java/org/apache/guacamole/rest/GuacamoleExceptionMapper.java
---
@@ -0,0 +1,110 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.apache.guacamole.rest;
+
+import com.google.inject.Inject;
+import com.google.inject.Singleton;
+import java.lang.annotation.Annotation;
+import java.lang.reflect.Method;
+import java.util.Map;
+import javax.servlet.http.HttpServletRequest;
+import javax.ws.rs.FormParam;
+import javax.ws.rs.QueryParam;
+import javax.ws.rs.core.Context;
+import javax.ws.rs.core.MediaType;
+import javax.ws.rs.core.Response;
+import javax.ws.rs.ext.ExceptionMapper;
+import javax.ws.rs.ext.Provider;
+import org.aopalliance.intercept.MethodInvocation;
+import org.apache.guacamole.GuacamoleException;
+import org.apache.guacamole.GuacamoleUnauthorizedException;
+import org.apache.guacamole.rest.auth.AuthenticationService;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A class that maps GuacamoleExceptions in a way that returns a
+ * custom response to the user via JSON rather than allowing the default
+ * web application error handling to take place.
+ */
+@Provider
+public class GuacamoleExceptionMapper
+ implements ExceptionMapper<GuacamoleException> {
+
+ /**
+ * The logger for this class.
+ */
+ private final Logger logger =
LoggerFactory.getLogger(GuacamoleExceptionMapper.class);
+
+ /**
+ * The request associated with this instance of this mapper.
+ */
+ @Context private HttpServletRequest request;
--- End diff --
Done.
---
