SE 2811, Lab 3: Designing a Garden

For labs 3 and 4, you will work in groups to develop a flower bed simulator. In this simulator, bees visit flowers for food, bees attack and slow down other bees, and flowers can drain energy. This might be used by a botanist to experiment with different mixes of bees and flowers. This lab will give you experience with applying the basic object-oriented design principles discussed in class (using the noun/verb method to identify domain classes and operations and documenting responsibilities) to a new problem.

Requirements

In addition to the above requirements,

• Your system must be a JavaFX application.
• Design all windows so they are 700 pixels high or less and 900 pixels wide or less. This is important so we can grade your solutions on school laptops using the default resolution.
• Time advances in the application by pressing the right arrow key; each keypress is to move the simulation forward one "tick" of time. You can implement others to do the same thing if you find it convenient, but you must implement the right arrow key. Consistency is important for grading. If you are not sure how to do this, ask for help!
• Bees are to move a programmer-specified distance each tick. Select a distance, like 10 pixels, that allows bees to move reasonably quickly across the screen without having to press the key a ridiculous number of times. If your solution is annoying to test, it will be annoying to grade!
• Use Euclidean distance between the (approximate) centers of objects to determine when a bee hits a flower or other bee.
• Each bee is to have an energy level. The bee loses one or more energy points on each tick and dies if the energy level reaches zero. Balance the energy levels and amounts lost on each tick so that bees do live a reasonable amount of time, long enough to see them run into other objects but not so long that it is difficult to verify that bees can die from starvation.
• Allow the user to adjust the number of flowers in the garden so it is straightforward to test what happens when there are very few flowers (the bees should die quickly) and there are very many flowers (the bees should live a long time).
• Bees also lose energy when they run into each other. The specifics of this are up to the team, but at least one bee needs to lose energy when there is a collision.
• The flower bed must include at least two types of flowers: one that provides a given number of units of energy (in the form of nectar) and one that drains energy from visitors. You can experiment with different forms of this, but the behavior of both the one that provides energy and the one that drains it must change from visitor to visitor. For example, a flower could drain energy from one bee and give it to another, or a nectar-producing flower could take several cycles to regenerate its energy. You will need multiple instances of each type of flower. Do ensure that flowers that drain energy do have an impact (leading to shorter lives for bees unless they get that energy back from other flowers), but ensure that impact is not so great as to result in simply killing any bee that visits it.
• Include at least two types of bees, with multiple instances of each.
• One of the bees must pick a flower at random and then move towards that flower. The bee will then move towards the flower until it reaches it, then a new flower is picked. Do not implement this as a bee that just moves randomly; no bee would move in that way. The logic of having a target flower that changes is important to the assignment.
• Another bee must have a different pattern such as flying in straight lines back and forth (covering the full garden) or moving in diagonals. Again, random movement is not interesting; follow some reasonable pattern.
• Each bee must have a simple, distinct graphic along with a graphical and numerical display of its energy level. Note you can use JavaFX Pane classes (such as VBox in the provided sample code - see below) to put a status indicator under a bee. Display the energy level in two ways: as a number (which must be appropriately sized and colored to so as to be clearly visible) and as a health bar (a line showing how close the bee is to dying). The health information must be on the screen near to its bee and it must move with the bee. Talk to your instructor if you are unsure how to implement this.
• A collection of JPEG images is being provided; you can use these for your bees and flowers, or you can provide your own.
• Flowers must also have simple, distinct graphics. Like the bees, each must have an indicator of its status next to it. For example, if the flower must recharge before dispensing nector to another bee, add a count-down indicator showing how long until the flower is recharged.
• On your primary window (scene), include a box that displays a key showing the types of flowers and bees (graphically) and briefly explaining the behavior of each. This is needed so instructors can verify the behavior.

Process and design constraints

• Your solution must include at least one interface or abstract class that the team writes.
• You are not required to apply any design patterns.
• Do not use pow to square numbers; it is very inefficient for this because it uses natural logs. Simply multiply instead. Note that Point2D has a distance method, and this class might be useful for other reasons as well.
• Note that the above requirements give some flexibility on how bees and flowers behave. You can implement alternatives, but they must have behaviors that are at least as complex as the behavior described in this writeup. For example, note that the random movement bee tracks the target flower so that the flower does not change until the bee arrives. Do not implement a "user-guided" bee as part of this lab; the goal is to encapsulate how different types of bees move, not to create a search-and-destroy game.
• Each group member is expected to complete a fair share of the work. Each group member needs to check in interfaces to his or her classes early in the project, and each must complete an initial version of his or her portion before the next lab session. Failing to complete your portion will make it difficult for us to assign you to groups in future labs, making it difficult for you to satisfy course outcomes.
• Unless there is a documented issue, all team members will receive the same grade on the lab. This means it is important that all members review the work to make sure all requirements are satisfied.
• Be careful with names. The distributed, sample JavaFX code has the name BeeSimulator; this name makes sense for that code, but not for your submission to this lab since you are implementing a full garden, not just a bee.

Lab 3 Submission

For lab 3, submit

• A domain-level class diagram, drawn using EA, as defined by the domain-level UML Standards document. Be sure to include either attributes or methods (or both) for every class, and be sure that all classes are associated with at least one other. Review a draft of diagram with your instructor by the end of the lab period to ensure you have the correct elements and structure.
  • Warning: JavaFX elements such as controllers and menus are not domain classes! Domain classes capture objects that (say) a botanist would know about.
• A detailed list of bee requirements, describing the behavior of each class of bees. Document this behavior as a collection of user stories, where the user is a botanist or a beekeeper attempting to observe the simulated behavior. Remember the story format: As a ______, I would like to _____ because _____. The first blank is a type of user, the second is an action, and the third is a reason. For example, "As a beekeeper, I would like to know how long all of the bees survive so I know I can ensure we plant enough flowers for the number of bees we intend to keep." The reason is important because understanding goals is important to ensure you meant the user's need.
• A (single) PDF listing all domain classes, including the responsibility (or responsibilities) for each, and documenting which (single) team member will implement that class. The quality of your responsibilities will be an important part of your grade. These should be written using the pattern "The XXX class is responsible to...." You can use tools such as MSWord and Google Docs to create the PDF.
• An initial version of the system that builds using IntelliJ in a Git repository. Your instructor will give directions on creating the repository. At a minimum, your system must create a JavaFX form and display a bee or flower. Note the package name must reflect the assignment; using "bee_simulator" does not make sense because this assignment does more than simulate bees. Be sure to check in the full project, including both the src and .idea folders but not .idea/workspace.xml or .class files. Your instructor and teammate(s) should be able to open the project in IntelliJ from your repository. Ask if you need help!
• Be sure any code you intend your instructor to grade is on the "main" (or master) branch. There is no value in using git branches on a short assignment such as this one.

The full implementation will be due as lab 4.

Support Files

• garden_jpgs.zip: Images you can use for your flowers and bees.
• bee_simulator.zip: sample code illustrating placing an image on a panel and using arrow keys to move it around. Your solution will differ from this in many ways, but key ones include capturing the location in domain level objects (rather than having "free floating" variables like beeXLocation) and you will use the arrow key to move forward in the simulation rather than direct objects. But this code contains lots of elements that will be useful in your solution.