UPDATE: Bugfix on access admin data.

programs/mutant-1/swen90006/fotbot/FotBot.java

@@ -56,6 +56,7 @@ public class FotBot
      * Constructs a new FotBot server with no users
      */
     public FotBot()
+	throws DuplicateUserException, InvalidUsernameException, InvalidPasswordException
     {
 	passwords = new HashMap<String, String>();
         stepData = new HashMap<String, List<Integer>>();
@@ -64,6 +65,9 @@ public class FotBot
 	currentDay = new Date(1, 1, 2021);
 
 	passwords.put(ADMIN_USERNAME, ADMIN_PASSWORD);
+        stepData.put(ADMIN_USERNAME, new ArrayList<Integer>());
+        latestUpdate.put(ADMIN_USERNAME, currentDay.copy());
+        friends.put(ADMIN_USERNAME, new HashSet<String>());
     }
 
     /**
@@ -150,7 +154,7 @@ public class FotBot
      * Assumption: the length of 'steps' is always less than or equal
      * to numbers of days since the last update
      *
-     * Assumption: username and password are non-null
+     * Assumption: username, password, and steps are non-null
      *
      * Assumption: 'steps' records the order of the days from oldest
      * (at index 0) to most recent (at index steps.length - 1)
@@ -191,6 +195,9 @@ public class FotBot
      *
      * @throws  NoSuchUserException if the user does not have an account
      * @throws  IncorrectPasswordException if the password is incorrect for this user
+     *
+     * Assumption: username, password, and friendUsername are non-null
+     * Assumption: friendUsername is a registered user.
      */
     public void addFriend(String username, String password, String friendUsername)
 	throws NoSuchUserException, IncorrectPasswordException
@@ -220,6 +227,8 @@ public class FotBot
      *
      * @throws  NoSuchUserException if either user ('username' or 'user') does not have an account
      * @throws  IncorrectPasswordException if the password is incorrect for username
+     *
+     * Assumption: username, password, and targetUser are non-null
      */
     public List<Integer> getStepData(String username, String password, String targetUser)
 	throws NoSuchUserException, IncorrectPasswordException
@@ -237,7 +246,6 @@ public class FotBot
 	return result;
     }
 
-    
     /**
      * Increment the current day by a number of days
      */

programs/mutant-2/swen90006/fotbot/FotBot.java

@@ -56,6 +56,7 @@ public class FotBot
      * Constructs a new FotBot server with no users
      */
     public FotBot()
+	throws DuplicateUserException, InvalidUsernameException, InvalidPasswordException
     {
 	passwords = new HashMap<String, String>();
         stepData = new HashMap<String, List<Integer>>();
@@ -64,6 +65,9 @@ public class FotBot
 	currentDay = new Date(1, 1, 2021);
 
 	passwords.put(ADMIN_USERNAME, ADMIN_PASSWORD);
+        stepData.put(ADMIN_USERNAME, new ArrayList<Integer>());
+        latestUpdate.put(ADMIN_USERNAME, currentDay.copy());
+        friends.put(ADMIN_USERNAME, new HashSet<String>());
     }
 
     /**
@@ -150,7 +154,7 @@ public class FotBot
      * Assumption: the length of 'steps' is always less than or equal
      * to numbers of days since the last update
      *
-     * Assumption: username and password are non-null
+     * Assumption: username, password, and steps are non-null
      *
      * Assumption: 'steps' records the order of the days from oldest
      * (at index 0) to most recent (at index steps.length - 1)
@@ -191,6 +195,9 @@ public class FotBot
      *
      * @throws  NoSuchUserException if the user does not have an account
      * @throws  IncorrectPasswordException if the password is incorrect for this user
+     *
+     * Assumption: username, password, and friendUsername are non-null
+     * Assumption: friendUsername is a registered user.
      */
     public void addFriend(String username, String password, String friendUsername)
 	throws NoSuchUserException, IncorrectPasswordException
@@ -220,6 +227,8 @@ public class FotBot
      *
      * @throws  NoSuchUserException if either user ('username' or 'user') does not have an account
      * @throws  IncorrectPasswordException if the password is incorrect for username
+     *
+     * Assumption: username, password, and targetUser are non-null
      */
     public List<Integer> getStepData(String username, String password, String targetUser)
 	throws NoSuchUserException, IncorrectPasswordException
@@ -237,7 +246,6 @@ public class FotBot
 	return result;
     }
 
-    
     /**
      * Increment the current day by a number of days
      */

programs/mutant-3/swen90006/fotbot/FotBot.java

@@ -56,6 +56,7 @@ public class FotBot
      * Constructs a new FotBot server with no users
      */
     public FotBot()
+	throws DuplicateUserException, InvalidUsernameException, InvalidPasswordException
     {
 	passwords = new HashMap<String, String>();
         stepData = new HashMap<String, List<Integer>>();
@@ -64,6 +65,9 @@ public class FotBot
 	currentDay = new Date(1, 1, 2021);
 
 	passwords.put(ADMIN_USERNAME, ADMIN_PASSWORD);
+        stepData.put(ADMIN_USERNAME, new ArrayList<Integer>());
+        latestUpdate.put(ADMIN_USERNAME, currentDay.copy());
+        friends.put(ADMIN_USERNAME, new HashSet<String>());
     }
 
     /**
@@ -150,7 +154,7 @@ public class FotBot
      * Assumption: the length of 'steps' is always less than or equal
      * to numbers of days since the last update
      *
-     * Assumption: username and password are non-null
+     * Assumption: username, password, and steps are non-null
      *
      * Assumption: 'steps' records the order of the days from oldest
      * (at index 0) to most recent (at index steps.length - 1)
@@ -191,6 +195,9 @@ public class FotBot
      *
      * @throws  NoSuchUserException if the user does not have an account
      * @throws  IncorrectPasswordException if the password is incorrect for this user
+     *
+     * Assumption: username, password, and friendUsername are non-null
+     * Assumption: friendUsername is a registered user.
      */
     public void addFriend(String username, String password, String friendUsername)
 	throws NoSuchUserException, IncorrectPasswordException
@@ -220,6 +227,8 @@ public class FotBot
      *
      * @throws  NoSuchUserException if either user ('username' or 'user') does not have an account
      * @throws  IncorrectPasswordException if the password is incorrect for username
+     *
+     * Assumption: username, password, and targetUser are non-null
      */
     public List<Integer> getStepData(String username, String password, String targetUser)
 	throws NoSuchUserException, IncorrectPasswordException
@@ -237,7 +246,6 @@ public class FotBot
 	return result;
     }
 
-    
     /**
      * Increment the current day by a number of days
      */

programs/mutant-4/swen90006/fotbot/FotBot.java

@@ -56,6 +56,7 @@ public class FotBot
      * Constructs a new FotBot server with no users
      */
     public FotBot()
+	throws DuplicateUserException, InvalidUsernameException, InvalidPasswordException
     {
 	passwords = new HashMap<String, String>();
         stepData = new HashMap<String, List<Integer>>();
@@ -64,6 +65,9 @@ public class FotBot
 	currentDay = new Date(1, 1, 2021);
 
 	passwords.put(ADMIN_USERNAME, ADMIN_PASSWORD);
+        stepData.put(ADMIN_USERNAME, new ArrayList<Integer>());
+        latestUpdate.put(ADMIN_USERNAME, currentDay.copy());
+        friends.put(ADMIN_USERNAME, new HashSet<String>());
     }
 
     /**
@@ -150,7 +154,7 @@ public class FotBot
      * Assumption: the length of 'steps' is always less than or equal
      * to numbers of days since the last update
      *
-     * Assumption: username and password are non-null
+     * Assumption: username, password, and steps are non-null
      *
      * Assumption: 'steps' records the order of the days from oldest
      * (at index 0) to most recent (at index steps.length - 1)
@@ -191,6 +195,9 @@ public class FotBot
      *
      * @throws  NoSuchUserException if the user does not have an account
      * @throws  IncorrectPasswordException if the password is incorrect for this user
+     *
+     * Assumption: username, password, and friendUsername are non-null
+     * Assumption: friendUsername is a registered user.
      */
     public void addFriend(String username, String password, String friendUsername)
 	throws NoSuchUserException, IncorrectPasswordException
@@ -220,6 +227,8 @@ public class FotBot
      *
      * @throws  NoSuchUserException if either user ('username' or 'user') does not have an account
      * @throws  IncorrectPasswordException if the password is incorrect for username
+     *
+     * Assumption: username, password, and targetUser are non-null
      */
     public List<Integer> getStepData(String username, String password, String targetUser)
 	throws NoSuchUserException, IncorrectPasswordException
@@ -237,7 +246,6 @@ public class FotBot
 	return result;
     }
 
-    
     /**
      * Increment the current day by a number of days
      */

programs/mutant-5/swen90006/fotbot/FotBot.java

@@ -56,6 +56,7 @@ public class FotBot
      * Constructs a new FotBot server with no users
      */
     public FotBot()
+	throws DuplicateUserException, InvalidUsernameException, InvalidPasswordException
     {
 	passwords = new HashMap<String, String>();
         stepData = new HashMap<String, List<Integer>>();
@@ -64,6 +65,9 @@ public class FotBot
 	currentDay = new Date(1, 1, 2021);
 
 	passwords.put(ADMIN_USERNAME, ADMIN_PASSWORD);
+        stepData.put(ADMIN_USERNAME, new ArrayList<Integer>());
+        latestUpdate.put(ADMIN_USERNAME, currentDay.copy());
+        friends.put(ADMIN_USERNAME, new HashSet<String>());
     }
 
     /**
@@ -150,7 +154,7 @@ public class FotBot
      * Assumption: the length of 'steps' is always less than or equal
      * to numbers of days since the last update
      *
-     * Assumption: username and password are non-null
+     * Assumption: username, password, and steps are non-null
      *
      * Assumption: 'steps' records the order of the days from oldest
      * (at index 0) to most recent (at index steps.length - 1)
@@ -191,6 +195,9 @@ public class FotBot
      *
      * @throws  NoSuchUserException if the user does not have an account
      * @throws  IncorrectPasswordException if the password is incorrect for this user
+     *
+     * Assumption: username, password, and friendUsername are non-null
+     * Assumption: friendUsername is a registered user.
      */
     public void addFriend(String username, String password, String friendUsername)
 	throws NoSuchUserException, IncorrectPasswordException
@@ -220,6 +227,8 @@ public class FotBot
      *
      * @throws  NoSuchUserException if either user ('username' or 'user') does not have an account
      * @throws  IncorrectPasswordException if the password is incorrect for username
+     *
+     * Assumption: username, password, and targetUser are non-null
      */
     public List<Integer> getStepData(String username, String password, String targetUser)
 	throws NoSuchUserException, IncorrectPasswordException
@@ -237,7 +246,6 @@ public class FotBot
 	return result;
     }
 
-    
     /**
      * Increment the current day by a number of days
      */

programs/original/swen90006/fotbot/FotBot.java

@@ -64,7 +64,10 @@ public class FotBot
         friends = new HashMap<String, Set<String>>();
 	currentDay = new Date(1, 1, 2021);
 
-	this.register(ADMIN_USERNAME, ADMIN_PASSWORD);
+	passwords.put(ADMIN_USERNAME, ADMIN_PASSWORD);
+        stepData.put(ADMIN_USERNAME, new ArrayList<Integer>());
+        latestUpdate.put(ADMIN_USERNAME, currentDay.copy());
+        friends.put(ADMIN_USERNAME, new HashSet<String>());
     }
 
     /**
@@ -194,6 +197,7 @@ public class FotBot
      * @throws  IncorrectPasswordException if the password is incorrect for this user
      *
      * Assumption: username, password, and friendUsername are non-null
+     * Assumption: friendUsername is a registered user.
      */
     public void addFriend(String username, String password, String friendUsername)
 	throws NoSuchUserException, IncorrectPasswordException