package seedu.doist.commons.core;

/**
 * Container for user visible messages.
 */
public class Messages {
    public static final String MESSAGE_UNKNOWN_COMMAND = "Unknown command";
    public static final String MESSAGE_INVALID_COMMAND_FORMAT = "Invalid command format! \n%1$s";
    public static final String MESSAGE_INVALID_TASK_DISPLAYED_INDEX = "The task index provided is invalid";
    public static final String MESSAGE_TASKS_LISTED_OVERVIEW = "%1$d tasks listed!";
    public static final String MESSAGE_TASKS_SORTED_OVERVIEW = "Tasks sorted by %1$s!";
}

package seedu.doist.commons.core;

/**
 * Container for user visible messages.
 */
public class Messages {
    public static final String MESSAGE_UNKNOWN_COMMAND = "Unknown command";
    public static final String MESSAGE_INVALID_COMMAND_FORMAT = "Invalid command format! \n%1$s";
    public static final String MESSAGE_INVALID_TASK_DISPLAYED_INDEX = "The task index provided is invalid";
    public static final String MESSAGE_TASKS_LISTED_OVERVIEW = "%1$d tasks listed!";
    public static final String MESSAGE_TASKS_SORTED_OVERVIEW = "Tasks sorted by %1$s!";
    public static final String MESSAGE_INVALID_DATES = "Incorrect dates used";
}

Add message for Invalid dates