Merge pull request #3 from muller317/branch-A-CodeQuality

Refactor command classes to reduce code duplication
muller317 · Sep 15, 2024 · e648bfc · e648bfc
2 parents 590eeec + c6079d0
commit e648bfc
Show file tree

Hide file tree

Showing 13 changed files with 116 additions and 53 deletions.
diff --git a/src/main/java/MainWindow.java b/src/main/java/MainWindow.java
@@ -25,6 +25,9 @@ public class MainWindow extends AnchorPane {
     private Image userImage = new Image(this.getClass().getResourceAsStream("/images/DaUser.png"));
     private Image mullerImage = new Image(this.getClass().getResourceAsStream("/images/DaMuller.png"));
 
+    /**
+     * Starts of the program with greetings and a GUI.
+     */
     @FXML
     public void initialize() {
         String welcomeMessage = "Hello! I'm Muller!\nWhat can I do for you?";

diff --git a/src/main/java/muller/Muller.java b/src/main/java/muller/Muller.java
@@ -37,7 +37,6 @@ public String getResponse(String input) {
         // Programmer-level assumption: input should not be null or empty
         assert input != null : "Input should not be null";
         assert !input.trim().isEmpty() : "Input should not be empty";
-
         Parser parser = new Parser();
         try {
             Command command = parser.parse(input);

diff --git a/src/main/java/muller/command/AddCommand.java b/src/main/java/muller/command/AddCommand.java
@@ -27,8 +27,8 @@ public AddCommand(String[] commandInputs, String taskType) {
 
     @Override
     public String execute(TaskList tasks, Ui ui, Storage storage) throws MullerException {
-        super.assertionTest(tasks, ui, storage);
-        if (commandInputs.length < 2) {
+        CommandUtil.assertionTest(tasks, ui, storage);
+        if (CommandUtil.isInputComplete(commandInputs)) {
             throw new MullerException(taskType.equals("T") ? "Todo what?"
                     : taskType.equals("D") ? "Deadline for what?" : "Event for what?");
         }
@@ -65,7 +65,7 @@ public String execute(TaskList tasks, Ui ui, Storage storage) throws MullerExcep
      */
     private Task parseDeadline(String details) throws MullerException {
         String[] detailParts = details.split("/by", 2);
-        if (detailParts.length < 2) {
+        if (CommandUtil.isInputComplete(detailParts)) {
             throw new MullerException("Oops, you didn't specify the deadline!");
         }
         Task task = new Task(detailParts[0].trim());
@@ -83,12 +83,12 @@ private Task parseDeadline(String details) throws MullerException {
      * @throws MullerException If the date format is invalid.
      */
     private Task parseEvent(String details) throws MullerException {
-        String[] detailParts = details.split("/from", 2);
-        if (detailParts.length < 2) {
+        String[] detailParts = details.split("/from", 2); //A String array that separates event name and relevant dates.
+        if (CommandUtil.isInputComplete(detailParts)) { //Checks if dates are specified.
             throw new MullerException("Oops, you didn't specify the start date!");
         }
-        String[] dateParts = detailParts[1].split("/to", 2);
-        if (dateParts.length < 2) {
+        String[] dateParts = detailParts[1].split("/to", 2); // A String array that separates start date and end date.
+        if (CommandUtil.isInputComplete(dateParts)) { //Checks if end date/start date is specified.
             throw new MullerException("You missed out either the start or end date!");
         }
         Task task = new Task(detailParts[0].trim());

diff --git a/src/main/java/muller/command/Command.java b/src/main/java/muller/command/Command.java
@@ -17,19 +17,6 @@ public abstract class Command {
      * @throws MullerException If an error occurs during command execution.
      */
     public abstract String execute(TaskList tasks, Ui ui, Storage storage) throws MullerException;
-
-    /**
-     * Checks if the input task, ui, storage are not null.
-     *
-     * @param tasks
-     * @param ui
-     * @param storage
-     */
-    public void assertionTest(TaskList tasks, Ui ui, Storage storage) {
-        assert tasks != null : "TaskList should not be null";
-        assert ui != null : "Ui should not be null";
-        assert storage != null : "Storage should not be null";
-    }
 }
 
 
diff --git a/src/main/java/muller/command/CommandUtil.java b/src/main/java/muller/command/CommandUtil.java
@@ -0,0 +1,89 @@
+package muller.command;
+
+import muller.storage.Storage;
+import muller.task.TaskList;
+import muller.ui.Ui;
+
+/**
+ * Utility class for common validation methods.
+ */
+public class CommandUtil {
+    /**
+     * Checks if the input task, ui, storage are not null.
+     *
+     * @param tasks
+     * @param ui
+     * @param storage
+     */
+    public static void assertionTest(TaskList tasks, Ui ui, Storage storage) {
+        assert tasks != null : "TaskList should not be null";
+        assert ui != null : "Ui should not be null";
+        assert storage != null : "Storage should not be null";
+    }
+
+    /**
+     * Checks if the input task index is valid.
+     *
+     * @param index
+     * @param taskListSize
+     * @return
+     */
+    public static boolean isValidTaskIndex(int index, int taskListSize) {
+        return index >= 0 && index < taskListSize;
+    }
+
+    /**
+     * Check if the input is complete for different tasks.
+     *
+     * @param commandInputs
+     * @return
+     */
+    public static boolean isInputComplete(String[] commandInputs) {
+        return commandInputs.length < 2;
+    }
+
+    /**
+     * Checks if the input string is a numeric value.
+     *
+     * @param str The input string.
+     * @return True if the string is numeric, false otherwise.
+     */
+    public static boolean isNumeric(String str) {
+        try {
+            Integer.parseInt(str);
+            return true;
+        } catch (NumberFormatException e) {
+            return false;
+        }
+    }
+
+    /**
+     * Check the command to delete tasks is complete
+     *
+     * @param commandInputs
+     * @return
+     */
+    public static boolean isDeleteCommandValid(String[] commandInputs) {
+        return commandInputs.length < 2 || !isNumeric(commandInputs[1]);
+    }
+
+    /**
+     * Check if the input is complete for different tasks.
+     *
+     * @param commandInputs
+     * @return
+     */
+    public static boolean isFindCommandValid(String[] commandInputs) {
+        return commandInputs.length < 2 || commandInputs[1].trim().isEmpty();
+    }
+
+    /**
+     * Check the command to delete tasks is complete
+     *
+     * @param commandInputs
+     * @return
+     */
+    public static boolean isMarkCommandValid(String[] commandInputs) {
+        return commandInputs.length < 2 || !isNumeric(commandInputs[1]);
+    }
+}
diff --git a/src/main/java/muller/command/DeleteCommand.java b/src/main/java/muller/command/DeleteCommand.java
@@ -1,6 +1,5 @@
 package muller.command;
 
-import muller.Muller;
 import muller.storage.Storage;
 import muller.task.Task;
 import muller.task.TaskList;
@@ -19,17 +18,19 @@ public class DeleteCommand extends Command {
      * @throws MullerException If the input is not a valid task number.
      */
     public DeleteCommand(String[] inputs) throws MullerException {
-        if (inputs.length < 2 || !isNumeric(inputs[1])) {
+        if (CommandUtil.isDeleteCommandValid(inputs)) {
             throw new MullerException("Pick a valid task number to delete!");
         }
+
+        //Resize the index to make sure align with 0-indexed list.
         this.index = Integer.parseInt(inputs[1]) - 1;
     }
 
     @Override
     public String execute(TaskList tasks, Ui ui, Storage storage) throws MullerException {
-        super.assertionTest(tasks, ui, storage);
+        CommandUtil.assertionTest(tasks, ui, storage);
         try {
-            if (index < 0 || index >= tasks.getSize()) {
+            if (CommandUtil.isValidTaskIndex(index, tasks.getSize())) {
                 throw new MullerException("Invalid task number!");
             }
             Task deletedTask = tasks.get(index);
@@ -40,19 +41,4 @@ public String execute(TaskList tasks, Ui ui, Storage storage) throws MullerExcep
             return e.getMessage();
         }
     }
-
-    /**
-     * Checks if the input string is a numeric value.
-     *
-     * @param str The input string.
-     * @return True if the string is numeric, false otherwise.
-     */
-    private boolean isNumeric(String str) {
-        try {
-            Integer.parseInt(str);
-            return true;
-        } catch (NumberFormatException e) {
-            return false;
-        }
-    }
 }
diff --git a/src/main/java/muller/command/ExitCommand.java b/src/main/java/muller/command/ExitCommand.java
@@ -10,7 +10,7 @@
 public class ExitCommand extends Command {
     @Override
     public String execute(TaskList tasks, Ui ui, Storage storage) {
-        super.assertionTest(tasks, ui, storage);
+        CommandUtil.assertionTest(tasks, ui, storage);
         return "Bye. Hope to see you again soon!";
     }
 }
diff --git a/src/main/java/muller/command/FindCommand.java b/src/main/java/muller/command/FindCommand.java
@@ -20,15 +20,15 @@ public class FindCommand extends Command {
      * @throws MullerException If the keyword is missing.
      */
     public FindCommand(String[] inputs) throws MullerException {
-        if (inputs.length < 2 || inputs[1].trim().isEmpty()) {
+        if (CommandUtil.isFindCommandValid(inputs)) {
             throw new MullerException("Please provide a keyword to search for!");
         }
         this.keyword = inputs[1].trim();
     }
 
     @Override
     public String execute(TaskList tasks, Ui ui, Storage storage) {
-        super.assertionTest(tasks, ui, storage);
+        CommandUtil.assertionTest(tasks, ui, storage);
         List<Task> matchingTasks = tasks.findTasksByKeyword(keyword);
         return ui.showMatchingTasks(matchingTasks);
     }

diff --git a/src/main/java/muller/command/ListCommand.java b/src/main/java/muller/command/ListCommand.java
@@ -10,7 +10,7 @@
 public class ListCommand extends Command {
     @Override
     public String execute(TaskList tasks, Ui ui, Storage storage) {
-        super.assertionTest(tasks, ui, storage);
+        CommandUtil.assertionTest(tasks, ui, storage);
         return ui.showTaskList(tasks);
     }
 }
diff --git a/src/main/java/muller/command/MarkCommand.java b/src/main/java/muller/command/MarkCommand.java
@@ -17,15 +17,15 @@ public class MarkCommand extends Command {
      * @throws MullerException If the input is not a valid task number.
      */
     public MarkCommand(String[] inputs) throws MullerException {
-        if (inputs.length < 2 || !isNumeric(inputs[1])) {
+        if (CommandUtil.isMarkCommandValid(inputs)) {
             throw new MullerException("Pick a valid task number to mark!");
         }
         this.index = Integer.parseInt(inputs[1]) - 1;
     }
 
     @Override
     public String execute(TaskList tasks, Ui ui, Storage storage) throws MullerException {
-        super.assertionTest(tasks, ui, storage);
+        CommandUtil.assertionTest(tasks, ui, storage);
         tasks.get(index).markAsDone();
         storage.saveTasks(tasks);
         return ui.showTaskMarked(tasks, index);

diff --git a/src/main/java/muller/command/OnCommand.java b/src/main/java/muller/command/OnCommand.java
@@ -22,7 +22,7 @@ public class OnCommand extends Command {
      * @throws MullerException If the input date format is invalid.
      */
     public OnCommand(String[] inputs) throws MullerException {
-        if (inputs.length < 2) {
+        if (CommandUtil.isInputComplete(inputs)) {
             throw new MullerException("Specify a date (e.g., 'on 2019-10-15')!");
         }
         try {
@@ -34,7 +34,7 @@ public OnCommand(String[] inputs) throws MullerException {
 
     @Override
     public String execute(TaskList tasks, Ui ui, Storage storage) {
-        super.assertionTest(tasks, ui, storage);
+        CommandUtil.assertionTest(tasks, ui, storage);
         return ui.showTaskOnDate(tasks, date);
     }
 }
diff --git a/src/main/java/muller/command/UnmarkCommand.java b/src/main/java/muller/command/UnmarkCommand.java
@@ -17,15 +17,15 @@ public class UnmarkCommand extends Command {
      * @throws MullerException If the input is not a valid task number.
      */
     public UnmarkCommand(String[] inputs) throws MullerException {
-        if (inputs.length < 2 || !isNumeric(inputs[1])) {
+        if (CommandUtil.isMarkCommandValid(inputs)) {
             throw new MullerException("Pick a valid task number to unmark!");
         }
         this.index = Integer.parseInt(inputs[1]) - 1;
     }
 
     @Override
     public String execute(TaskList tasks, Ui ui, Storage storage) throws MullerException {
-        super.assertionTest(tasks, ui, storage);
+        CommandUtil.assertionTest(tasks, ui, storage);
         tasks.get(index).markAsNotDone();
         storage.saveTasks(tasks);
         return ui.showTaskUnMarked(tasks, index);

diff --git a/src/main/java/muller/ui/Ui.java b/src/main/java/muller/ui/Ui.java
@@ -2,7 +2,6 @@
 
 import java.time.LocalDate;
 import java.util.List;
-import java.util.Scanner;
 
 import muller.command.MullerException;
 import muller.task.Task;
@@ -54,7 +53,7 @@ public String showTaskMarked(TaskList tasks, int index) {
         try {
             return ("Nice! I've marked this task as done:\n"
                     + "  " + tasks.get(index));
-        } catch (MullerException e){
+        } catch (MullerException e) {
             return e.getMessage();
         }
     }
@@ -69,7 +68,7 @@ public String showTaskUnMarked(TaskList tasks, int index) {
         try {
             return ("OK, I've marked this task as not done yet:\n"
                     + "  " + tasks.get(index));
-        } catch (MullerException e){
+        } catch (MullerException e) {
             return e.getMessage();
         }
     }