JP2 2019 1 Lab Exam Practice
JP2 2019: Lab exam practice task
This specification is provided to allow you to practice for the lab exam. This problem is similar in
structure and difficulty to the problem you will do in your own lab exam. You can work on this
problem in advance on your own, and also during your scheduled lab session on 25/26 November
where your tutor and demonstrator will be present. A sample solution will be provided after the
lab session.
Note that no starter code will be provided; you will need to create a new project in Eclipse to
implement the classes. See the separately provided sheet for details of creating a new Eclipse
projects, including the necessary steps to fix the configuration problem that normally occurs.
Overview
Your task is to create a set of classes representing playable characters in a video game, as well as a
class representing a player of that video game. The following are the main features that you will
implement – the remainder of this lab sheet describes in more detail how the classes should be
created.
Every Game Character has two properties: a name and a set of powers. Here are some example
characters and their powers:
• Robin (Weapons)
• Starfire (Flight, Energy Blast)
• Cyborg (Strength, Weapons)
• Beast Boy (Transformation)
• Raven (Magic)
Every Player of a video game has a set of game characters that are available to use.
For the player to play the game, they need to choose a set of characters with specific powers, and if
they do not have the necessary powers they cannot play. For example, if the player has all of the
above characters, the following are the characters they should choose in various circumstances:
• If the required powers are Weapons and Strength, they should choose Cyborg
• If the required powers are Flight, Strength, and Transformation, they should choose
Starfire, Cyborg, and Beast Boy.
• If the required powers are Weapons and Magic, they could choose either Robin and Raven,
or Cyborg and Raven.
• If the required powers are Transformation, Magic, and Science, then this player cannot play
as they do not have any characters that provide all of the required powers.
JP2 2019 2 Lab Exam Practice
Task 1: Power (2 marks)
Note about implementation: all classes created in this exam should be put in the superhero package.
You must create an enumerated type Power with the following values:
CLONING, COMPUTER, ENERGY_BLAST, FLIGHT, INVINCIBILITY, MAGIC, MAGNETISM,
SCIENCE, SMALL, SPEED, STRENGTH, TELEPATHY, TRANSFORMATION, WEAPONS, WATER
Task 2: GameCharacter (6 marks)
You must create a class GameCharacter representing a game character including the following
properties:
• name (a String)
• powers (a collection of Power objects – use whatever data type you feel is appropriate)
You must create a constructor to set the value of the above fields with the following signature:
public GameCharacter(String name, Power[] powers)
In addition, your GameCharacter class must satisfy the following requirements:
• The class must have a complete set of get methods for all fields, but no set methods
• The class should provide appropriate implementations of equals(), hashCode(), and
toString().
Task 3: Player (5 marks)
Once your GameCharacter class is finished, you should implement a Player class to represent a
player of the game, making use of the GameCharacter class defined above. Player should have a
single field:
• The group of game characters that they currently own (represented as GameCharacter
objects) – you can choose whatever data type you want for this field
Player should also have the following methods – note that you are not required to override
equals(), hashCode(), or toString() for this class.
• A constructor that initialises the group of characters correctly
• A get method to retrieve the field value.
JP2 2019 3 Lab Exam Practice
Task 4: chooseCharacters (6 marks)
In your Player class, implement one additional public method, as follows:
• public List chooseCharacters(Power[] neededPowers)
This method should implement the behaviour shown above in the example: given a set of powers, it
should return the characters required to provide all of the requested powers. If no characters can be
found to cover all of the required powers, this method should return null. If more than one group of
characters can provide the required powers, any valid group can be returned (as in the example
above with Weapons and Magic).
Marking
Indicative values for each part of the exam are given above – the marking of the actual lab exam will
be similar. Partial marks will be allocated for partially working solutions. In addition, one mark will be
allocated for coding style, including aspects such as:
- Using standard Java-style class and variable names
- Appropriate use of commenting
- Appropriate code formatting and indentation