Improved exception handling for 301, null response body and connection issues

src/main/java/com/rohitawate/restaurant/dashboard/DashboardController.java

@@ -17,6 +17,7 @@ package com.rohitawate.restaurant.dashboard;
 
 import com.jfoenix.controls.JFXButton;
 import com.jfoenix.controls.JFXSnackbar;
+import com.rohitawate.restaurant.exceptions.UnreliableResponseException;
 import com.rohitawate.restaurant.models.requests.DELETERequest;
 import com.rohitawate.restaurant.models.requests.DataDispatchRequest;
 import com.rohitawate.restaurant.models.requests.GETRequest;
@@ -37,13 +38,12 @@ import javafx.scene.layout.BorderPane;
 import javafx.scene.layout.HBox;
 import javafx.scene.layout.VBox;
 
+import javax.ws.rs.ProcessingException;
 import javax.ws.rs.core.Response;
 import java.io.FileNotFoundException;
 import java.io.IOException;
-import java.net.ConnectException;
 import java.net.MalformedURLException;
 import java.net.URL;
-import java.net.UnknownHostException;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.ResourceBundle;
@@ -115,6 +115,9 @@ public class DashboardController implements Initializable {
         snackBar = new JFXSnackbar(dashboard);
         bodyTab.disableProperty().bind(Bindings.and(httpMethodBox.valueProperty().isNotEqualTo("POST"),
                 httpMethodBox.valueProperty().isNotEqualTo("PUT")));
+
+        errorTitle.setText("Oops... That's embarrassing!");
+        errorDetails.setText("Something went wrong. Try to make another request.\nRestart RESTaurant if that doesn't work.");
     }
 
     @FXML
@@ -166,13 +169,18 @@ public class DashboardController implements Initializable {
                     });
                     requestManager.setOnFailed(e -> {
                         loadingLayer.setVisible(false);
-                        errorLayer.setVisible(true);
+                        promptLayer.setVisible(false);
-                        Throwable exception = requestManager.getException().getCause();
+                        Throwable exception = requestManager.getException();
 
-                        if (exception.getClass() == UnknownHostException.class) {
+                        if (exception.getClass() == UnreliableResponseException.class) {
-                            errorTitle.setText("No Internet Connection");
+                            UnreliableResponseException URE = (UnreliableResponseException) exception;
-                            errorDetails.setText("Could not connect to the server. Please check your connection.");
+                            errorTitle.setText(URE.getExceptionTitle());
+                            errorDetails.setText(URE.getExceptionDetails());
+                        } else if (exception.getClass() == ProcessingException.class) {
+                            errorTitle.setText("RESTaurant couldn't connect.");
+                            errorDetails.setText("Either you are not connected to the Internet or the server is offline.");
                         }
+                        errorLayer.setVisible(true);
                         requestManager.reset();
                     });
                     requestManager.start();
@@ -213,11 +221,19 @@ public class DashboardController implements Initializable {
                     });
                     requestManager.setOnFailed(e -> {
                         loadingLayer.setVisible(false);
-                        promptLayer.setVisible(true);
+                        promptLayer.setVisible(false);
-                        if (requestManager.getException().getClass() == ConnectException.class)
+                        Throwable exception = requestManager.getException();
-                            snackBar.show("Request timed out. Server is unavailable or didn't respond.", 10000);
+
-                        else if (requestManager.getException().getClass() == FileNotFoundException.class)
+                        if (exception.getClass() == UnreliableResponseException.class) {
+                            UnreliableResponseException URE = (UnreliableResponseException) exception;
+                            errorTitle.setText(URE.getExceptionTitle());
+                            errorDetails.setText(URE.getExceptionDetails());
+                        } else if (exception.getClass() == ProcessingException.class) {
+                            errorTitle.setText("RESTaurant couldn't connect.");
+                            errorDetails.setText("Either you are not connected to the Internet or the server is offline.");
+                        } else if (exception.getClass() == FileNotFoundException.class)
                             snackBar.show("File could not be found.", 5000);
+                        errorLayer.setVisible(true);
                         requestManager.reset();
                     });
                     requestManager.start();
@@ -253,13 +269,18 @@ public class DashboardController implements Initializable {
                     });
                     requestManager.setOnFailed(e -> {
                         loadingLayer.setVisible(false);
-                        errorLayer.setVisible(true);
+                        promptLayer.setVisible(false);
-                        Throwable exception = requestManager.getException().getCause();
+                        Throwable exception = requestManager.getException();
 
-                        if (exception.getClass() == UnknownHostException.class) {
+                        if (exception.getClass() == UnreliableResponseException.class) {
+                            UnreliableResponseException URE = (UnreliableResponseException) exception;
+                            errorTitle.setText(URE.getExceptionTitle());
+                            errorDetails.setText(URE.getExceptionDetails());
+                        } else if (exception.getClass() == ProcessingException.class) {
                             errorTitle.setText("No Internet Connection");
                             errorDetails.setText("Could not connect to the server. Please check your connection.");
                         }
+                        errorLayer.setVisible(true);
                         requestManager.reset();
                     });
                     requestManager.start();

src/main/java/com/rohitawate/restaurant/exceptions/UnreliableResponseException.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2018 Rohit Awate.
+ *
+ * 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 com.rohitawate.restaurant.exceptions;
+
+/**
+ * Thrown when the server sends ambiguous responses.
+ * For example, some servers do not provide the new location in case of a 301 Moved Permanently.
+ * <p>
+ * Used by DashboardController to display ErrorLayer.
+ */
+public class UnreliableResponseException extends Exception {
+    private String exceptionTitle;
+    private String exceptionDetails;
+
+    public UnreliableResponseException(String exceptionTitle, String exceptionDetails) {
+        this.exceptionTitle = exceptionTitle;
+        this.exceptionDetails = exceptionDetails;
+    }
+
+    public void setExceptionTitle(String exceptionTitle) {
+        this.exceptionTitle = exceptionTitle;
+    }
+
+    public void setExceptionDetails(String exceptionDetails) {
+        this.exceptionDetails = exceptionDetails;
+    }
+
+    public String getExceptionTitle() {
+        return exceptionTitle;
+    }
+
+    public String getExceptionDetails() {
+        return exceptionDetails;
+    }
+}

src/main/java/com/rohitawate/restaurant/requestsmanager/DELETERequestManager.java

@@ -19,6 +19,7 @@ package com.rohitawate.restaurant.requestsmanager;
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.SerializationFeature;
+import com.rohitawate.restaurant.exceptions.UnreliableResponseException;
 import com.rohitawate.restaurant.models.requests.DELETERequest;
 import com.rohitawate.restaurant.models.responses.RestaurantResponse;
 import javafx.concurrent.Task;
@@ -26,7 +27,6 @@ import javafx.concurrent.Task;
 import javax.ws.rs.client.Invocation;
 import javax.ws.rs.client.WebTarget;
 import javax.ws.rs.core.Response;
-import java.io.IOException;
 import java.util.HashMap;
 import java.util.Map;
 
@@ -58,22 +58,22 @@ public class DELETERequestManager extends RequestManager {
                 response.setTime(initialTime, System.currentTimeMillis());
 
                 if (serverResponse == null)
-                    throw new IOException();
+                    throw new UnreliableResponseException("The server did not respond.",
+                            "Like that crush from high school..");
                 else if (serverResponse.getStatus() == 301) {
-                    response.setStatusCode(301);
                     String newLocation = serverResponse.getHeaderString("location");
-                    String responseHelpText;
 
+                    String responseHelpText;
                     if (newLocation == null)
-                        responseHelpText = "The resource has been permanently moved to another location.\n\n" +
+                        responseHelpText = "The resource has been permanently moved to another location.\n" +
                                 "Here's what you can do:\n" +
                                 "- Find the new URL from the API documentation.\n" +
                                 "- Try using https instead of http if you're not already.";
                     else
-                        responseHelpText = "The resource has been permanently moved to: " + newLocation;
+                        responseHelpText = "The resource has been permanently moved to: " + newLocation +
+                                "\nRESTaurant doesn't automatically redirect your requests.";
 
-                    response.setBody(responseHelpText);
+                    throw new UnreliableResponseException("301: Resource Moved Permanently", responseHelpText);
-                    return response;
                 }
 
                 String type = (String) serverResponse.getHeaders().getFirst("Content-type");
@@ -82,6 +82,7 @@ public class DELETERequestManager extends RequestManager {
                 ObjectMapper mapper = new ObjectMapper();
                 mapper.configure(SerializationFeature.INDENT_OUTPUT, true);
 
+                if (type != null) {
                     switch (type.toLowerCase()) {
                         case "application/json; charset=utf-8":
                         case "application/json":
@@ -99,6 +100,9 @@ public class DELETERequestManager extends RequestManager {
                         default:
                             response.setBody(responseBody);
                     }
+                } else {
+                    response.setBody("No body found in the response.");
+                }
 
                 response.setMediaType(serverResponse.getMediaType());
                 response.setStatusCode(serverResponse.getStatus());

src/main/java/com/rohitawate/restaurant/requestsmanager/DataDispatchRequestManager.java

@@ -19,6 +19,7 @@ package com.rohitawate.restaurant.requestsmanager;
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.SerializationFeature;
+import com.rohitawate.restaurant.exceptions.UnreliableResponseException;
 import com.rohitawate.restaurant.models.requests.DataDispatchRequest;
 import com.rohitawate.restaurant.models.responses.RestaurantResponse;
 import javafx.concurrent.Task;
@@ -32,7 +33,10 @@ import javax.ws.rs.client.WebTarget;
 import javax.ws.rs.core.Form;
 import javax.ws.rs.core.MediaType;
 import javax.ws.rs.core.Response;
-import java.io.*;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.InputStream;
 import java.util.HashMap;
 import java.util.Map;
 
@@ -132,22 +136,22 @@ public class DataDispatchRequestManager extends RequestManager {
                 response.setTime(initialTime, System.currentTimeMillis());
 
                 if (serverResponse == null)
-                    throw new IOException();
+                    throw new UnreliableResponseException("The server did not respond.",
+                            "Like that crush from high school..");
                 else if (serverResponse.getStatus() == 301) {
-                    response.setStatusCode(301);
                     String newLocation = serverResponse.getHeaderString("location");
-                    String responseHelpText;
 
+                    String responseHelpText;
                     if (newLocation == null)
-                        responseHelpText = "The resource has been permanently moved to another location.\n\n" +
+                        responseHelpText = "The resource has been permanently moved to another location.\n" +
                                 "Here's what you can do:\n" +
                                 "- Find the new URL from the API documentation.\n" +
                                 "- Try using https instead of http if you're not already.";
                     else
-                        responseHelpText = "The resource has been permanently moved to: " + newLocation;
+                        responseHelpText = "The resource has been permanently moved to: " + newLocation +
+                                "\nRESTaurant doesn't automatically redirect your requests.";
 
-                    response.setBody(responseHelpText);
+                    throw new UnreliableResponseException("301: Resource Moved Permanently", responseHelpText);
-                    return response;
                 }
 
                 String type = (String) serverResponse.getHeaders().getFirst("Content-type");
@@ -156,6 +160,7 @@ public class DataDispatchRequestManager extends RequestManager {
                 ObjectMapper mapper = new ObjectMapper();
                 mapper.configure(SerializationFeature.INDENT_OUTPUT, true);
 
+                if (type != null) {
                     switch (type.toLowerCase()) {
                         case "application/json; charset=utf-8":
                         case "application/json":
@@ -173,6 +178,9 @@ public class DataDispatchRequestManager extends RequestManager {
                         default:
                             response.setBody(responseBody);
                     }
+                } else {
+                    response.setBody("No body found in the response.");
+                }
 
                 response.setMediaType(serverResponse.getMediaType());
                 response.setStatusCode(serverResponse.getStatus());

src/main/java/com/rohitawate/restaurant/requestsmanager/GETRequestManager.java

@@ -19,13 +19,13 @@ package com.rohitawate.restaurant.requestsmanager;
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.SerializationFeature;
+import com.rohitawate.restaurant.exceptions.UnreliableResponseException;
 import com.rohitawate.restaurant.models.responses.RestaurantResponse;
 import javafx.concurrent.Task;
 
 import javax.ws.rs.client.Invocation.Builder;
 import javax.ws.rs.client.WebTarget;
 import javax.ws.rs.core.Response;
-import java.io.IOException;
 import java.util.HashMap;
 import java.util.Map;
 
@@ -53,22 +53,22 @@ public class GETRequestManager extends RequestManager {
                 response.setTime(initialTime, System.currentTimeMillis());
 
                 if (serverResponse == null)
-                    throw new IOException();
+                    throw new UnreliableResponseException("The server did not respond.",
+                            "Like that crush from high school..");
                 else if (serverResponse.getStatus() == 301) {
-                    response.setStatusCode(301);
                     String newLocation = serverResponse.getHeaderString("location");
-                    String responseHelpText;
 
+                    String responseHelpText;
                     if (newLocation == null)
-                        responseHelpText = "The resource has been permanently moved to another location.\n\n" +
+                        responseHelpText = "The resource has been permanently moved to another location.\n" +
                                 "Here's what you can do:\n" +
                                 "- Find the new URL from the API documentation.\n" +
                                 "- Try using https instead of http if you're not already.";
                     else
-                        responseHelpText = "The resource has been permanently moved to: " + newLocation;
+                        responseHelpText = "The resource has been permanently moved to: " + newLocation +
+                                "\nRESTaurant doesn't automatically redirect your requests.";
 
-                    response.setBody(responseHelpText);
+                    throw new UnreliableResponseException("301: Resource Moved Permanently", responseHelpText);
-                    return response;
                 }
 
                 String type = (String) serverResponse.getHeaders().getFirst("Content-type");
@@ -77,6 +77,7 @@ public class GETRequestManager extends RequestManager {
                 ObjectMapper mapper = new ObjectMapper();
                 mapper.configure(SerializationFeature.INDENT_OUTPUT, true);
 
+                if (type != null) {
                     switch (type.toLowerCase()) {
                         case "application/json; charset=utf-8":
                         case "application/json":
@@ -94,6 +95,9 @@ public class GETRequestManager extends RequestManager {
                         default:
                             response.setBody(responseBody);
                     }
+                } else {
+                    response.setBody("No body found in the response.");
+                }
 
                 response.setMediaType(serverResponse.getMediaType());
                 response.setStatusCode(serverResponse.getStatus());