cave-sprint-2

The source code and design documents for the Cave game according to Sprint 2

Proposed workflow for implementing the new design changes

This is the proposed work flow (work in progress, check here often as this will be added to continously).

Start with the new responsibilities for Player - then change the GUI

Add the following methods to the Player class:

+describeCurrentRoom() : String
+thingsInCurrentRoom() : Thing [*]
+canSeeDoorIn(direction : Room.Direction) : boolean

It is pretty straight forward what they should do. Remember that the rationale for these changes, is that the GUI/UI shouldn't have to deal with the Player's current Room, but rather directly with the Player.

In each of the methods, just query the currentRoom variable for the thing to return.

When the Player compiles, implement these changes in the GUI. What places? The place in the GUI where before, you used Player.getInstance().currentRoom() .

These are the places to look for:

$ grep -n 'currentRoom()' se/itu/game/gui/MainFrame.java
118:    Room currentRoom = player.currentRoom();
140:    for (Thing thing : player.currentRoom().things()) {
180:    roomInfo.setText(player.currentRoom().description());
184:    Room currentRoom = player.currentRoom();

Add the new Exception classes

Implement the classes se.itu.game.cave.IllegalMoveException and game.itu.game.cave.RuleViolationException .

It's pretty straight forward - Let them extend Exception and add a constructor accepting a String message and in the constructor body, simply call super(message); . See the lecture slides for the code examples.

Change the Player's instance method go(Room.Direction direction)

Now, change the Player's instance method go(Room.Direction) so that it throws IllegalMoveException in its declaration. Also reflect this in the javadoc for the method.

When Player compiles, reflect this change in the GUI. You need to add try-catch(IllegalMoveException e) in the places where you call "player.go(direction)".

$ grep -n 'go(' se/itu/game/gui/MainFrame.java
188:            player.go(dir);

Implement the ThingRule interface

See the UML and the lecture slides for hints. The interface should declare one public abstract method:

/+apply() : boolean {exceptions=RuleViolationException}/

The UML syntax above means abstract and that it throws RuleViolationException

Implement the RuleBook class

Write the class se.itu.game.cave.RuleBook which should have the following variables and methods:

_-rules: Map<Thing, ThingRule>_
--
_+addThingRule(thing : Thing, rule : ThingRule) : void_
_+getRuleFor(thing : Thing) : ThingRule_

That is, a private static Map<Thing, ThingRule> (you need to import java.util.Map and java.util.HashMap), and a public static void addThingRule method which accepts a Thing and a ThingRule and adds them to the map using the method put(thing, rule), and finally a public static getRuleFor method which accepts a Thing and returns it using the method get(thing) on the map. See lecture slides for hints.

Don't worry about the adding of ThingRules to the map using the addThingRule method. It is done from the new version of CaveInitializer.java in this repository. And, yeah, now that you have both a RuleBook and the ThingRule interface, you should be able to compile both the CaveInitializer.java and the test class ThingRuleTest.java !

Implement the new version of Player's takeThing so that it gets the ThingRule and applies it

Next, change the Player's instance method takeThing(Thing) so that it uses an if-statement which gets the corresponding ThingRule from the RuleBook and calls apply() inside the if-test.

In the if-block, do as before. See the lecture slides for hints.

Don't forget that according to the new design, takeThing(...) should now declare that it throws RuleViolationException, to force the GUI code to try-catch it.

Verify that the ThingRuleTest passes

Use the ./build.sh script (if you are running bash) to build the whole project. Then use the ./run_tests.sh script to run the tests.

I you don't run bash (in Mac OS or Cygwin), you can look inside the scripts and do the same manually.

Reflect the changes to takeThing in the GUI code

You should now change the GUI so that it uses try-catch to notice rule violations. Where to check? (note that line numbers have probably changed now that you've added stuff, but originally it was this):

$ grep -n 'takeThing(' se/itu/game/gui/MainFrame.java
230:          Player.getInstance().takeThing(thing);

I you don't run bash (in Mac OS or Cygwin), you can look inside the scripts and do the same manually.

Verify that the GUI works with the rules check and everything.

Run the gui (how to is included in the script ./run_gui.sh ) and verify that everything works. To be continued and/or updated. Stay tuned!