Github user mike-jumper commented on a diff in the pull request:
https://github.com/apache/guacamole-client/pull/291#discussion_r191607055
--- 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;
+
+ /**
+ * The authentication service associated with the currently active
session.
+ */
+ @Inject
+ private AuthenticationService authenticationService;
+
+ /**
+ * Returns the authentication token that is in use in the current
session,
+ * if present, or null if otherwise.
+ *
+ * @return
+ * The authentication token for the current session, or null if no
+ * token is present.
+ */
+ private String getAuthenticationToken() {
+
+ @SuppressWarnings("unchecked")
+ Map<String, String[]> parameters = request.getParameterMap();
+
+ for (String paramName : parameters.keySet()) {
+ if (paramName.equals("token")) {
--- End diff --
There's no need to iterate over the key set of a `Map` to find the entry
having a particular key. Part of the point of a `Map` is the ability to
retrieve such an entry by its key.
parameters.get("token")
In this case, there's no need to go through the map, as you can retrieve
the parameter from the request directly:
request.getParameter("token")
---
