some request/response changes

modules/feed-comm/src/main/java/org/hawkular/feedcomm/ws/FeedCommWebSocket.java

@@ -27,9 +27,10 @@
 import javax.websocket.Session;
 import javax.websocket.server.ServerEndpoint;
 
+import org.hawkular.feedcomm.ws.command.BasicResponse;
 import org.hawkular.feedcomm.ws.command.Command;
 import org.hawkular.feedcomm.ws.command.EchoCommand;
-import org.hawkular.feedcomm.ws.command.ErrorResponse;
+import org.hawkular.feedcomm.ws.command.ErrorDetails;
 
 @ServerEndpoint("/")
 public class FeedCommWebSocket {
@@ -63,7 +64,7 @@ public String clientMessage(String commandAndJsonStr, Session client) {
         Class<? extends Command> commandClass = VALID_COMMANDS.get(commandName);
         if (commandClass == null) {
             MsgLogger.LOG.errorInvalidCommandName(commandName);
-            return JsonUtil.toJson(new ErrorResponse("Invalid command name: " + commandName));
+            return new BasicResponse(new ErrorDetails("Invalid command name: " + commandName)).toJson();
         }
 
         String response;
@@ -73,7 +74,7 @@ public String clientMessage(String commandAndJsonStr, Session client) {
             response = command.execute(json);
         } catch (Throwable t) {
             MsgLogger.LOG.errorCommandExecutionFailure(commandName, json, t);
-            response = JsonUtil.toJson(new ErrorResponse("Failed to execute command [" + commandName + "]", t));
+            response = new BasicResponse(new ErrorDetails("Command failed[" + commandName + "]", t)).toJson();
         }
 
         return response;

modules/feed-comm/src/main/java/org/hawkular/feedcomm/ws/command/BasicRequest.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2015 Red Hat, Inc. and/or its affiliates
+ * and other contributors as indicated by the @author tags.
+ *
+ * Licensed 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.hawkular.feedcomm.ws.command;
+
+import org.hawkular.feedcomm.ws.JsonUtil;
+
+public class BasicRequest {
+
+    /**
+     * Constructs a basic request.
+     */
+    public BasicRequest() {
+    }
+
+    /**
+     * Serialize this object into JSON.
+     *
+     * @return this object's JSON representation
+     */
+    public String toJson() {
+        String json = JsonUtil.toJson(this);
+        return json;
+    }
+}

modules/feed-comm/src/main/java/org/hawkular/feedcomm/ws/command/BasicResponse.java

@@ -0,0 +1,76 @@
+/*
+ * Copyright 2015 Red Hat, Inc. and/or its affiliates
+ * and other contributors as indicated by the @author tags.
+ *
+ * Licensed 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.hawkular.feedcomm.ws.command;
+
+import org.hawkular.feedcomm.ws.JsonUtil;
+
+import com.fasterxml.jackson.annotation.JsonInclude;
+
+public class BasicResponse {
+    public enum ResultStatus {
+        OK, ERROR
+    }
+
+    @JsonInclude
+    private final ResultStatus resultStatus;
+
+    @JsonInclude
+    private final ErrorDetails errorDetails;
+
+    /**
+     * Constructs a basic "OK" response.
+     */
+    public BasicResponse() {
+        this.resultStatus = ResultStatus.OK;
+        this.errorDetails = null;
+
+    }
+
+    /**
+     * Constructs an error response.
+     *
+     * @param errorDetails error details
+     */
+    public BasicResponse(ErrorDetails errorDetails) {
+        this.resultStatus = ResultStatus.ERROR;
+        this.errorDetails = errorDetails;
+    }
+
+    public ResultStatus getResultStatus() {
+        return this.resultStatus;
+    }
+
+    /**
+     * Provides details on the error that occurred, if one did occur.
+     * This will be <code>null</code> if {@link #getResultStatus()} is {@link ResultStatus#OK}.
+     *
+     * @return if this result was an error, this describes the error that occurred
+     */
+    public ErrorDetails getErrorDetails() {
+        return this.errorDetails;
+    }
+
+    /**
+     * Serialize this object into JSON.
+     *
+     * @return this object's JSON representation
+     */
+    public String toJson() {
+        String json = JsonUtil.toJson(this);
+        return json;
+    }
+}

modules/feed-comm/src/main/java/org/hawkular/feedcomm/ws/command/EchoCommand.java

@@ -30,7 +30,6 @@ public String execute(String json) {
         String reply = String.format("ECHO [%s]", echoMessage.echoMessage);
 
         // return the JSON response
-        EchoResponse echoResponse = new EchoResponse(reply);
-        return JsonUtil.toJson(echoResponse);
+        return new EchoResponse(reply).toJson();
     }
 }

modules/feed-comm/src/main/java/org/hawkular/feedcomm/ws/command/EchoRequest.java

@@ -19,7 +19,7 @@
 
 import com.fasterxml.jackson.annotation.JsonInclude;
 
-public class EchoRequest {
+public class EchoRequest extends BasicRequest {
     @JsonInclude
     public String echoMessage;
 

modules/feed-comm/src/main/java/org/hawkular/feedcomm/ws/command/EchoResponse.java

@@ -19,14 +19,21 @@
 
 import com.fasterxml.jackson.annotation.JsonInclude;
 
-public class EchoResponse {
+public class EchoResponse extends BasicResponse {
+
     @JsonInclude
-    public String replyMessage;
+    public String reply;
 
     public EchoResponse() {
+        super();
+    }
+
+    public EchoResponse(ErrorDetails errorDetails) {
+        super(errorDetails);
     }
 
-    public EchoResponse(String replyMessage) {
-        this.replyMessage = replyMessage;
+    public EchoResponse(String reply) {
+        super();
+        this.reply = reply;
     }
 }

modules/feed-comm/src/main/java/org/hawkular/feedcomm/ws/command/ErrorResponse.java → modules/feed-comm/src/main/java/org/hawkular/feedcomm/ws/command/ErrorDetails.java

@@ -19,28 +19,28 @@
 import com.fasterxml.jackson.annotation.JsonInclude;
 
 /**
- * A generic error response that can be JSON-encoded.
+ * Contains some details that describe an error that occurred.
  */
-public class ErrorResponse {
+public class ErrorDetails {
 
     @JsonInclude
-    private final String message;
+    private final String errorMessage;
 
     @JsonInclude
     private final String exception;
 
-    public ErrorResponse(String message) {
-        this.message = message;
+    public ErrorDetails(String errorMessage) {
+        this.errorMessage = errorMessage;
         this.exception = null;
     }
 
-    public ErrorResponse(Throwable throwable) {
-        this.message = null;
+    public ErrorDetails(Throwable throwable) {
+        this.errorMessage = null;
         this.exception = throwable.toString();
     }
 
-    public ErrorResponse(String message, Throwable throwable) {
-        this.message = message;
+    public ErrorDetails(String errorMessage, Throwable throwable) {
+        this.errorMessage = errorMessage;
         this.exception = throwable.toString();
     }