Logic: Add alias for commands

src/main/java/seedu/address/logic/commands/AddCommand.java

@@ -18,6 +18,7 @@
 public class AddCommand extends UndoableCommand {
 
     public static final String COMMAND_WORD = "add";
+    public static final String COMMAND_ALIAS = "a";
 
     public static final String MESSAGE_USAGE = COMMAND_WORD + ": Adds a person to the address book. "
             + "Parameters: "

src/main/java/seedu/address/logic/commands/ClearCommand.java

@@ -10,6 +10,7 @@
 public class ClearCommand extends UndoableCommand {
 
     public static final String COMMAND_WORD = "clear";
+    public static final String COMMAND_ALIAS = "c";
     public static final String MESSAGE_SUCCESS = "Address book has been cleared!";
 
 

src/main/java/seedu/address/logic/commands/DeleteCommand.java

@@ -13,6 +13,7 @@
 public class DeleteCommand extends UndoableCommand {
 
     public static final String COMMAND_WORD = "delete";
+    public static final String COMMAND_ALIAS = "d";
 
     public static final String MESSAGE_USAGE = COMMAND_WORD
             + ": Deletes the person identified by the index number used in the last person listing.\n"

src/main/java/seedu/address/logic/commands/EditCommand.java

@@ -31,6 +31,7 @@
 public class EditCommand extends UndoableCommand {
 
     public static final String COMMAND_WORD = "edit";
+    public static final String COMMAND_ALIAS = "e";
 
     public static final String MESSAGE_USAGE = COMMAND_WORD + ": Edits the details of the person identified "
             + "by the index number used in the last person listing. "

src/main/java/seedu/address/logic/commands/FindCommand.java

@@ -9,6 +9,7 @@
 public class FindCommand extends Command {
 
     public static final String COMMAND_WORD = "find";
+    public static final String COMMAND_ALIAS = "f";
 
     public static final String MESSAGE_USAGE = COMMAND_WORD + ": Finds all persons whose names contain any of "
             + "the specified keywords (case-sensitive) and displays them as a list with index numbers.\n"

src/main/java/seedu/address/logic/commands/HistoryCommand.java

@@ -15,6 +15,7 @@
 public class HistoryCommand extends Command {
 
     public static final String COMMAND_WORD = "history";
+    public static final String COMMAND_ALIAS = "h";
     public static final String MESSAGE_SUCCESS = "Entered commands (from most recent to earliest):\n%1$s";
     public static final String MESSAGE_NO_HISTORY = "You have not yet entered any commands.";
 

src/main/java/seedu/address/logic/commands/ListCommand.java

@@ -7,6 +7,7 @@
 public class ListCommand extends Command {
 
     public static final String COMMAND_WORD = "list";
+    public static final String COMMAND_ALIAS = "l";
 
     public static final String MESSAGE_SUCCESS = "Listed all persons";
 

src/main/java/seedu/address/logic/commands/RedoCommand.java

@@ -13,6 +13,7 @@
 public class RedoCommand extends Command {
 
     public static final String COMMAND_WORD = "redo";
+    public static final String COMMAND_ALIAS = "r";
     public static final String MESSAGE_SUCCESS = "Redo success!";
     public static final String MESSAGE_FAILURE = "No more commands to redo!";
 

src/main/java/seedu/address/logic/commands/SelectCommand.java

@@ -14,6 +14,7 @@
 public class SelectCommand extends Command {
 
     public static final String COMMAND_WORD = "select";
+    public static final String COMMAND_ALIAS = "s";
 
     public static final String MESSAGE_USAGE = COMMAND_WORD
             + ": Selects the person identified by the index number used in the last person listing.\n"

src/main/java/seedu/address/logic/commands/UndoCommand.java

@@ -13,6 +13,7 @@
 public class UndoCommand extends Command {
 
     public static final String COMMAND_WORD = "undo";
+    public static final String COMMAND_ALIAS = "u";
     public static final String MESSAGE_SUCCESS = "Undo success!";
     public static final String MESSAGE_FAILURE = "No more commands to undo!";
 

src/main/java/seedu/address/logic/parser/AddressBookParser.java

@@ -49,27 +49,35 @@ public Command parseCommand(String userInput) throws ParseException {
         switch (commandWord) {
 
         case AddCommand.COMMAND_WORD:
+        case AddCommand.COMMAND_ALIAS:
             return new AddCommandParser().parse(arguments);
 
         case EditCommand.COMMAND_WORD:
+        case EditCommand.COMMAND_ALIAS:
             return new EditCommandParser().parse(arguments);
 
         case SelectCommand.COMMAND_WORD:
+        case SelectCommand.COMMAND_ALIAS:
             return new SelectCommandParser().parse(arguments);
 
         case DeleteCommand.COMMAND_WORD:
+        case DeleteCommand.COMMAND_ALIAS:
             return new DeleteCommandParser().parse(arguments);
 
         case ClearCommand.COMMAND_WORD:
+        case ClearCommand.COMMAND_ALIAS:
             return new ClearCommand();
 
         case FindCommand.COMMAND_WORD:
+        case FindCommand.COMMAND_ALIAS:
             return new FindCommandParser().parse(arguments);
 
         case ListCommand.COMMAND_WORD:
+        case ListCommand.COMMAND_ALIAS:
             return new ListCommand();
 
         case HistoryCommand.COMMAND_WORD:
+        case HistoryCommand.COMMAND_ALIAS:
             return new HistoryCommand();
 
         case ExitCommand.COMMAND_WORD:
@@ -79,9 +87,11 @@ public Command parseCommand(String userInput) throws ParseException {
             return new HelpCommand();
 
         case UndoCommand.COMMAND_WORD:
+        case UndoCommand.COMMAND_ALIAS:
             return new UndoCommand();
 
         case RedoCommand.COMMAND_WORD:
+        case RedoCommand.COMMAND_ALIAS:
             return new RedoCommand();
 
         default: