level 9 - Find

src/main/java/speed/command/FindCommand.java

@@ -0,0 +1,22 @@
+package speed.command;
+
+import speed.exception.SpeedException;
+import speed.storage.Storage;
+import speed.task.Task;
+import speed.task.TaskList;
+import speed.ui.Ui;
+
+import java.util.ArrayList;
+
+public class FindCommand extends Command {
+    private final String keyword;
+    public FindCommand(String keyword) {
+        this.keyword = keyword;
+    }
+
+    @Override
+    public void execute(TaskList tasks, Ui ui, Storage storage) throws SpeedException {
+        ArrayList<Task> matchedTasks = tasks.find(keyword);
+        ui.showFindList(matchedTasks);
+    }
+}

src/main/java/speed/parser/Parser.java

@@ -5,6 +5,7 @@
 import speed.command.DeleteCommand;
 import speed.command.EventCommand;
 import speed.command.ExitCommand;
+import speed.command.FindCommand;
 import speed.command.HelpCommand;
 import speed.command.ListCommand;
 import speed.command.MarkCommand;
@@ -63,6 +64,9 @@ public static Command parseCommand(String input, int totalTaskCount) throws Spee
             Event task = parseEvent(input);
             return new EventCommand(task);
 
+        } else if (input.equals("find") || input.startsWith("find ") ) {
+            String keyword = parseFind(input);
+            return new FindCommand(keyword);
         } else {
             throw new SpeedException(Ui.ERROR_UNKNOWN_COMMAND);
         }
@@ -164,4 +168,14 @@ private static Todo parseTodo(String input) throws SpeedException {
         }
         return new Todo(description);
     }
+
+    private static String parseFind(String input) throws SpeedException {
+        String[] parts = input.split(" ", 2);
+        String keyword = parts.length < 2 ? "" : parts[1].trim();
+
+        if (keyword.isEmpty()) {
+            throw new SpeedException(Ui.ERROR_MISSING_KEYWORD);
+        }
+        return keyword;
+    }
 }

src/main/java/speed/task/TaskList.java

@@ -2,6 +2,8 @@
 
 import java.util.ArrayList;
 
+import static java.util.stream.Collectors.toList;
+
 /**
  * Represents a list of tasks with operations to manage them.
  */
@@ -98,4 +100,15 @@ public boolean isEmpty() {
     public ArrayList<Task> getTasks() {
         return tasks;
     }
+
+    public ArrayList<Task> find (String keyword) {
+        String key = keyword.toLowerCase();
+
+        ArrayList<Task> matchedTasks = (ArrayList<Task>) tasks.stream()
+                        .filter(t -> t.getDescription()
+                                .toLowerCase()
+                                .contains(key))
+                        .collect(toList());
+        return matchedTasks;
+    }
 }

src/main/java/speed/ui/Ui.java

@@ -3,6 +3,7 @@
 import speed.task.Task;
 import speed.task.TaskList;
 
+import java.util.ArrayList;
 import java.util.Scanner;
 
 /**
@@ -16,6 +17,9 @@ public class Ui {
     public static final String ERROR_EMPTY_TODO =
             "Hold up! You forgot to give a description of the todo!!";
 
+    public static final String ERROR_MISSING_KEYWORD =
+            "Give me a keyword of what you want me to find bro!";
+
     public static final String ERROR_NO_TASK_NUMBER =
             "Please give me the task number as well bro.";
 
@@ -117,7 +121,8 @@ public void printCommandList() {
         System.out.println("5.mark <Task number>");
         System.out.println("6.unmark <Task number>");
         System.out.println("7.delete <Task number>");
-        System.out.println("8.bye");
+        System.out.println("8.find <keyword>");
+        System.out.println("9.bye");
         printLine();
     }
 
@@ -202,4 +207,21 @@ public void showTaskDeleted(Task task, int remainingTasksCount) {
         System.out.println("Now you have " + remainingTasksCount + " tasks in the list.");
         printLine();
     }
+
+    public void showFindList(ArrayList<Task> matchedTasks) {
+        if (matchedTasks.isEmpty()) {
+            printLine();
+            System.out.println("No matches found!");
+            printLine();
+        } else {
+            printLine();
+            System.out.println("Here are the matching tasks in your list:");
+            int taskCount = 1;
+            for (Task task : matchedTasks) {
+                System.out.println((taskCount++) + "." + task.displayString());
+            }
+            printLine();
+        }
+
+    }
 }