Merge branch 'branch-Level-9'

# Conflicts:
#	src/main/java/duke/task/Task.java
#	src/main/java/duke/task/TaskList.java

src/main/java/duke/common/Message.java

@@ -10,7 +10,7 @@ public class Message {
     public static final String MESSAGE_ADDED = "Got it. I've added this task:";
     public static final String MESSAGE_DELETED = "Noted. I've removed this task:";
     public static final String MESSAGE_MARK_DONE = "Nice! I've marked this task as done:";
-    public static final String MESSAGE_SHOW_TASK_LIST = "Here are the tasks in your list:";
+    public static final String MESSAGE_SHOW_TASK_LIST = "Here are the%1$s tasks in your list:";
     public static final String MESSAGE_SHOW_TASK_SIZE = "Now you have %1$s tasks in the list.";
     public static final String MESSAGE_INVALID_COMMAND_FORMAT = "I'm sorry, but I don't know what that means :-(";
     public static final String MESSAGE_INVALID_TODO_FORMAT = "The description of a todo cannot be empty.";
@@ -19,6 +19,7 @@ public class Message {
     public static final String MESSAGE_INVALID_EVENT_FORMAT =
             "Events must have /at and cannot be empty. E.g. event project meeting /at 2/12/2019 1800";
     public static final String MESSAGE_INVALID_TASK_INDEX = "Invalid task number. Task numbers follow 1-based indexing.";
+    public static final String MESSAGE_INVALID_KEYWORD_FORMAT = "Invalid keyword. Specify keyword to search for tasks.";
     public static final String MESSAGE_ERROR_MISSING_STORAGE_FILE = "%1$sMissing storage file: %2$s";
     public static final String MESSAGE_ERROR_CREATING_STORAGE_FILE = "Unable to create new file %1$s. %2$s";
     public static final String MESSAGE_STORAGE_FILE_CREATED = "%1$sCreated new empty storage file: %2$s";

src/main/java/duke/parser/Parser.java

@@ -39,6 +39,8 @@ public static Command parse(String inputLine) throws DukeException {
                 return new AddCommand(createEventFrom(inputLine));
             case "delete":
                 return new DeleteCommand(getIndexFrom(inputLine));
+            case "find":
+                return new FindCommand(getKeywordFrom(inputLine));
             default:
                 throw new DukeException(Message.MESSAGE_INVALID_COMMAND_FORMAT);
         }
@@ -97,4 +99,12 @@ private static Event createEventFrom(String inputLine) throws DukeException {
             throw new DukeException((Message.MESSAGE_INVALID_DATE_FORMAT));
         }
     }
+
+    private static String getKeywordFrom(String inputLine) throws DukeException {
+        String keyword = inputLine.substring("find".length()).strip();
+        if (keyword.isEmpty()) {
+            throw new DukeException(Message.MESSAGE_INVALID_KEYWORD_FORMAT);
+        }
+        return keyword;
+    }
 }

src/main/java/duke/task/Task.java

@@ -19,6 +19,13 @@ public Task(String taskName) {
         this.isDone = false;
     }
 
+    /**
+     * @return the name of this task.
+     */
+    public String getTaskName() {
+        return this.taskName;
+    }
+
     /**
      * Sets this task to the given done status.
      *

src/main/java/duke/task/TaskList.java

@@ -23,7 +23,6 @@ public TaskList() {
      *
      * @param tasks list of tasks.
      */
-
     public TaskList(List<Task> tasks) {
         this.tasks = tasks;
     }
@@ -76,6 +75,20 @@ public List<String> getTaskNames() {
         return taskNames;
     }
 
+    /**
+     * @param keyword keyword that is used for finding tasks.
+     * @return a list of task names and descriptions of tasks that contain this <code>keyword</code>.
+     */
+    public List<String> getTaskNamesIfMatch(String keyword) {
+        List<String> taskNamesThatMatch = new ArrayList<>();
+        for (int i = 0; i < tasks.size(); i++) {
+            if (tasks.get(i).getTaskName().contains(keyword)) {
+                taskNamesThatMatch.add((i + 1) + ". " + tasks.get(i));
+            }
+        }
+        return taskNamesThatMatch;
+    }
+
     /**
      * @return a list of simplified summaries of all tasks in the list.
      */

src/main/java/duke/ui/UserInterface.java

@@ -96,7 +96,7 @@ public void showDeletion(Task task) {
      * @param taskNames names of the tasks.
      */
     public void showTaskList(List<String> taskNames) {
-        showToUser(Message.MESSAGE_SHOW_TASK_LIST);
+        showToUser(String.format(Message.MESSAGE_SHOW_TASK_LIST, " matching"));
         for (String taskName : taskNames) {
             showToUser(taskName);
         }