Create BrowserException.java, completed lab assignments

.classpath

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<classpath>
+	<classpathentry kind="src" path="src"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
+	<classpathentry kind="output" path="bin"/>
+</classpath>

src/BrowserException.java

@@ -0,0 +1,28 @@
+
+public class BrowserException extends Exception {
+
+	public BrowserException() {
+		// TODO Auto-generated constructor stub
+	}
+
+	public BrowserException(String message) {
+		super(message);
+		// TODO Auto-generated constructor stub
+	}
+
+	public BrowserException(Throwable cause) {
+		super(cause);
+		// TODO Auto-generated constructor stub
+	}
+
+	public BrowserException(String message, Throwable cause) {
+		super(message, cause);
+		// TODO Auto-generated constructor stub
+	}
+
+	public BrowserException(String message, Throwable cause, boolean enableSuppression, boolean writableStackTrace) {
+		super(message, cause, enableSuppression, writableStackTrace);
+		// TODO Auto-generated constructor stub
+	}
+
+}

src/BrowserModel.java

@@ -4,6 +4,7 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.ResourceBundle;
 
 
 /**
@@ -21,45 +22,54 @@ public class BrowserModel {
     private int myCurrentIndex;
     private List<URL> myHistory;
     private Map<String, URL> myFavorites;
+    private ResourceBundle myResources;
 
+
+    public static final String DEFAULT_RESOURCE_PACKAGE = "resources/";
 
     /**
      * Creates an empty model.
      */
     public BrowserModel () {
         myHome = null;
+
         myCurrentURL = null;
         myCurrentIndex = -1;
         myHistory = new ArrayList<>();
         myFavorites = new HashMap<>();
+        myResources = ResourceBundle.getBundle(DEFAULT_RESOURCE_PACKAGE + "ErrorMessages");
     }
 
     /**
      * Returns the first page in next history, null if next history is empty.
      */
-    public URL next () {
+    public URL next () throws BrowserException {
         if (hasNext()) {
             myCurrentIndex++;
             return myHistory.get(myCurrentIndex);
         }
-        return null;
+        else {
+        	throw new BrowserException(String.format(myResources.getString("ErrorOnNext")));
+        }
     }
 
     /**
      * Returns the first page in back history, null if back history is empty.
      */
-    public URL back () {
+    public URL back () throws BrowserException {
         if (hasPrevious()) {
             myCurrentIndex--;
             return myHistory.get(myCurrentIndex);
         }
-        return null;
+        else {
+        	throw new BrowserException(String.format(myResources.getString("ErrorOnBack")));
+        }
     }
 
     /**
      * Changes current page to given URL, removing next history.
      */
-    public URL go (String url) {
+    public URL go (String url) throws BrowserException{
         try {
             URL tmp = completeURL(url);
             // unfortunately, completeURL may not have returned a valid URL, so test it
@@ -76,7 +86,7 @@ public URL go (String url) {
             return myCurrentURL;
         }
         catch (Exception e) {
-            return null;
+            throw new BrowserException(String.format(myResources.getString("ErrorOnShowPage"), url));
         }
     }
 
@@ -124,11 +134,13 @@ public void addFavorite (String name) {
     /**
      * Returns URL from favorites associated with given name, null if none set.
      */
-    public URL getFavorite (String name) {
+    public URL getFavorite (String name) throws BrowserException {
         if (name != null && !name.equals("") && myFavorites.containsKey(name)) {
-            return myFavorites.get(name);
+        	return myFavorites.get(name);
+        }
+        else {
+        	throw new BrowserException(String.format(myResources.getString("ErrorOnFavorite")));
         }
-        return null;
     }
 
     // deal with a potentially incomplete URL

src/BrowserView.java

@@ -62,6 +62,7 @@ public class BrowserView {
     private Button myNextButton;
     private Button myHomeButton;
     // favorites
+    private Button myFavoriteButton;
     private ComboBox<String> myFavorites;
     // get strings from resource file
     private ResourceBundle myResources;
@@ -91,12 +92,12 @@ public BrowserView (BrowserModel model, String language) {
      * Display given URL.
      */
     public void showPage (String url) {
-        URL valid = myModel.go(url);
-        if (valid != null) {
+        try {
+        	URL valid = myModel.go(url);
             update(valid);
         }
-        else {
-            showError("Could not load " + url);
+        catch (BrowserException e) {
+            showError(e.getMessage());
         }
     }
 
@@ -126,12 +127,22 @@ public void showError (String message) {
 
     // move to the next URL in the history
     private void next () {
-        update(myModel.next());
+        try {
+        	update(myModel.next());
+        }
+        catch (BrowserException e) {
+        	showError(e.getMessage());
+        }
     }
 
     // move to the previous URL in the history
     private void back () {
-        update(myModel.back());
+       try {
+    	   update(myModel.back());
+       }
+       catch (BrowserException e) {
+    	   showError(e.getMessage());
+       }
     }
 
     // change current URL to the home page, if set
@@ -141,9 +152,14 @@ private void home () {
 
     // change page to favorite choice
     private void showFavorite (String favorite) {
-        showPage(myModel.getFavorite(favorite).toString());
-        // reset favorites ComboBox so the same choice can be made again
-        myFavorites.setValue(null);
+        try {
+        	showPage(myModel.getFavorite(favorite).toString());
+        	// reset favorites ComboBox so the same choice can be made again
+        	myFavorites.setValue(null);
+        }
+        catch (BrowserException e) {
+        	showError(e.getMessage());
+        }
     }
 
     // update just the view to display given URL
@@ -213,6 +229,7 @@ public void handle (ActionEvent event) {
         result.getChildren().add(myNextButton);
         myHomeButton = makeButton("HomeCommand", event -> home());
         result.getChildren().add(myHomeButton);
+
         // if user presses button or enter in text field, load/show the URL
         EventHandler<ActionEvent> showHandler = new ShowPage();
         result.getChildren().add(makeButton("GoCommand", showHandler));
@@ -225,7 +242,14 @@ public void handle (ActionEvent event) {
     private Node makePreferencesPanel () {
         HBox result = new HBox();
         myFavorites = new ComboBox<String>();
-        // ADD REST OF CODE HERE
+        myFavorites.setValue(myResources.getString("FavoriteFirstItem"));
+        myFavoriteButton = makeButton("FavoritePromptTitle", event -> addFavorite());
+        myFavorites.valueProperty().addListener(listener -> showFavorite(myFavorites.getValue()));
+        result.getChildren().add(myFavoriteButton);
+        result.getChildren().add(myFavorites);
+
+
+
         result.getChildren().add(makeButton("SetHomeCommand", event -> {
             myModel.setHome();
             enableButtons();

src/resources/ErrorMessages.properties

@@ -0,0 +1,4 @@
+ErrorOnShowPage=Could not load %s sorry dawg
+ErrorOnFavorite=Not valid favorite page
+ErrorOnBack=No back page exists
+ErrorOnNext=No next page exists