Merge pull request #137 from junhyeong0411/master

Add exception for file changes in event.txt

Author: junhyeong0411

src/main/java/seedu/duke/storage/EventStorage.java

@@ -3,6 +3,8 @@
 import seedu.duke.calendar.Event;
 import seedu.duke.calendar.EventList;
 import seedu.duke.calendar.Goal;
+import seedu.duke.flashcard.FlashcardList;
+import seedu.duke.storage.exceptions.EventFileFormatException;
 
 import java.io.File;
 import java.io.FileNotFoundException;
@@ -13,6 +15,8 @@
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
+import static seedu.duke.storage.EventStorageParser.eventFileChecker;
+
 
 /**
  * storage for Events
@@ -45,11 +49,20 @@ public EventList loadEvents() throws FileNotFoundException{
         File f = new File (this.path);
         Scanner s = new Scanner(f);
 
-        while(s.hasNext()){
-            String[] eventTokens = s.nextLine().split(" \\| ");
-            eventList.addEvent(EventStorageParser.loadEvent(eventTokens));
+        try{
+            while(s.hasNext()){
+                String[] eventTokens = s.nextLine().split(" \\| ");
+                eventFileChecker(eventTokens);
+                eventList.addEvent(EventStorageParser.loadEvent(eventTokens));
+            }
+        } catch (EventFileFormatException e) {
+            System.out.println("The flashcard save file is corrupted");
+            System.out.println("Automatically making new file");
+            eventList = new EventList(new ArrayList<>());
+            saveEvents(eventList.getEvents());
         }
 
+
         logger.log(Level.INFO, String.format(
                 "    There are currently %d events in the save file",
                 eventList.getSize()));

src/main/java/seedu/duke/storage/EventStorageParser.java

@@ -2,15 +2,45 @@
 
 import seedu.duke.calendar.Event;
 import seedu.duke.calendar.Goal;
+import seedu.duke.storage.exceptions.EventFileFormatException;
+import seedu.duke.storage.exceptions.FlashcardFileFormatException;
 
 import java.time.LocalDateTime;
+import java.time.format.DateTimeParseException;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
 public class EventStorageParser {
 
     private static Logger logger; // for logging
 
+    /**
+     * check the saved file format
+     * token length should be 3 or 4
+     * if token length is 3, format should be string, localdatetime, localdatetime
+     * if token length is 4, format should be string, localdatetime, int, int
+     * @param tokens is a split txt line
+     * @throws EventFileFormatException
+     */
+    public static void eventFileChecker(String[] tokens) throws EventFileFormatException {
+        if(tokens.length != 3 && tokens.length != 4) {
+            throw new EventFileFormatException();
+        }
+
+        try {
+            LocalDateTime.parse(tokens[1].trim());
+            if(tokens.length == 3){
+                LocalDateTime.parse(tokens[2].trim());
+            }
+            if(tokens.length == 4){
+                Integer.parseInt(tokens[2].trim());
+                Integer.parseInt(tokens[3].trim());
+            }
+        } catch (DateTimeParseException | NumberFormatException e) {
+            throw new EventFileFormatException();
+        }
+    }
+
 
     /**
      * load an event from certain format

src/main/java/seedu/duke/storage/FlashcardStorageParser.java

@@ -18,11 +18,13 @@ public final class FlashcardStorageParser {
      * check the saved file format
      * token length should be 4
      * type should be integer, string, string, integer
-     * @param tokens
+     * @param tokens is a split txt line
      * @throws FlashcardFileFormatException
      */
     public static void flashcardFileChecker(String[] tokens) throws FlashcardFileFormatException {
-        if(tokens.length != 4) throw new FlashcardFileFormatException();
+        if(tokens.length != 4) {
+            throw new FlashcardFileFormatException();
+        }
 
         try {
             Integer.parseInt(tokens[0].trim());