develop simulation of fish in a fish tank. The goal is to practice Object Oriented Concepts and Comparable, MouseListener and MouseMotionListener Interfaces.

The fish tank has 2 modes of status, fish manipulation and simulation.

In the fish manipulation status, the user can:

add new fish to the tank,

drag a fish to a different slot,

To implement these manipulation functionalities, you need to implement three functions: MouseClicked, MouseDragged and MouseReleased.

MouseClicked:

Verify that the application is in manipulation mode.

Construct a new fish object at the clicked point with a random colour

If the selected slot is not occupied by another fish, add the new fish to the tank

Paint

MouseDragged:

Verify that the application is in manipulation mode.

Set mouseDragged to true

Find out which fish is selected from the tank

MouseReleased:

Verify that mouseDragged is true

Verify that the selected slot is empty

Update the position of the selected fish by the selected slot

Paint

Do not forget to reset the selected fish index and mouseDragged flag

In the simulation mode, each fish independent of the other ones in the fish tank swim in random order.

They can move maximum one slot in each dimension at each fishTick trigger or they can stay in their current slot.

If there is another fish in the slot a fish decided to move, then the fish stays in its current slot.

To implement these simulation functionalities, you need to develop body of the following functions:

CompareTo function of the Fish class:

Compare with respect to mX values

If mX values are equal, compare with respect to mY values

You need to use CompareTo function in the Move, MouseDragged, MouseReleased and MouseClicked

Move function of the Fish class:

Randomly compute a move in x direction as -1, 0, 1

Randomly compute a move in y direction as -1, 0, 1

Compare the new slot of the fish with slots of the other fish in the tank:

If the new slot is occupied, stay in the old slot, and return

If the new slot is out of the tank, stay in the old slot, and return

Paint function of the Fish class:

Draw a filled circle in the center of the selected slot with the fish color

If your fish is drawn as a nice-looking fish as follows (in minimum), then you will get 1 point bonus. Use your creativity.

Please pay attention that I used the Singleton Design Pattern to allow usage of global variables. It is an often used and a very useful design pattern.

Please also pay attention to how we define the Fish class and how Fish class instances independent of each other behave in the Fish Tank.

FishTank.java

import java.awt.BorderLayout;

import java.awt.Color;

import java.awt.Graphics;

import javax.swing.JButton;

import java.awt.event.ActionListener;

import java.awt.event.ActionEvent;

import java.awt.event.ItemEvent;

import java.awt.event.ItemListener;

import java.awt.event.MouseEvent;

import java.util.ArrayList;

import java.util.Calendar;

import java.util.Random;

import javax.swing.JPanel;

import javax.swing.JToggleButton;

import javax.swing.JToolBar;

import javax.swing.JFrame;

import java.util.Timer;

import java.util.TimerTask;

import javax.swing.border.EtchedBorder;

class GlobalVariables {

public ArrayList mFish;

public FishTank mFishTank;

private GlobalVariables() {

mFish = new ArrayList();

mFishTank = new FishTank();

}

private static GlobalVariables instance;

public static GlobalVariables getInstance() {

if (instance == null){

instance = new GlobalVariables();

}

return instance;

}

}

class Fish implements Comparable{

int mX;

int mY;

int mId;

Color mColor;

public Fish(int id, int x, int y, Color color){

mId = id;

mX = x;

mY = y;

mColor = color;

}

public void paint(Graphics g){

// Implement this function

}

public void move(){

// Implement this function

}

@Override

public int compareTo(Fish o) {

// Implement this function

}

}

class FishTick extends TimerTask{

@Override

public void run() {

if (FishTank.mSimulateStatus){

for (int x=0;x

Fish f = GlobalVariables.getInstance().mFish.get(x);

f.move();

GlobalVariables.getInstance().mFish.set(x, f);

}

GlobalVariables.getInstance().mFishTank.mDrawPanel.paint();

}

}

}

public class FishTank extends javax.swing.JFrame implements java.awt.event.MouseListener, java.awt.event.MouseMotionListener{

private final int mNumRows = 20;

private final int mNumCols = 20;

private final int mGridSz = 30;

private int mSelectedFishIndex = -1;

private boolean mDragged = false;

private int mTopHeight;

JToolBar mToolbar;

JToggleButton mSimulationButton;

DrawPanel mDrawPanel;

private int mFishIndex = 0;

static public boolean mSimulateStatus = false;

public static void main(String[] args) {

GlobalVariables global = GlobalVariables.getInstance();

if (global == null){

System.out.println("Cannot initialize, exiting ....");

return;

}

}

private JToggleButton addButton(String title){

JToggleButton button = new JToggleButton(title);

button.addItemListener(new ItemListener() {

public void itemStateChanged(ItemEvent ev) {

mSimulateStatus = !mSimulateStatus;

}

});

this.mToolbar.add(button);

return (button);

}

public FishTank()

{

JFrame guiFrame = new JFrame();

guiFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

guiFrame.setTitle("MY FISH TANK");

// Create a toolbar and give it an etched border.

this.mToolbar = new JToolBar();

this.mToolbar.setBorder(new EtchedBorder());

mSimulationButton = addButton("Simulate");

this.mToolbar.add(mSimulationButton);

//This will center the JFrame in the middle of the screen

guiFrame.setLocationRelativeTo(null);

this.mDrawPanel = new DrawPanel(mNumRows, mNumCols, mGridSz);

this.mDrawPanel.setBackground(Color.cyan);

this.mDrawPanel.paint();

guiFrame.add(mDrawPanel);

guiFrame.add(this.mToolbar, BorderLayout.NORTH);

// Add the Exit Action

JButton button = new JButton("Quit");

button.setToolTipText("Quit the program");

button.addActionListener(new ActionListener() {

public void actionPerformed(ActionEvent e) {

System.exit(0);

}

});

mToolbar.add(button);

guiFrame.addMouseListener(this);

guiFrame.addMouseMotionListener(this);

//make sure the JFrame is visible

guiFrame.setVisible(true);

mTopHeight = guiFrame.getInsets().top + mToolbar.getHeight();

guiFrame.setSize(mNumRows * mGridSz, mNumCols * mGridSz + mTopHeight);

Timer timer = new Timer("tick", true);

timer.scheduleAtFixedRate(new FishTick(), Calendar.getInstance().get(Calendar.MILLISECOND), 500);

}

@Override

public void mouseClicked(MouseEvent e) {

// Implement this function

}

@Override

public void mousePressed(MouseEvent e) {

}

@Override

public void mouseReleased(MouseEvent e) {

// Implement this function

}

@Override

public void mouseEntered(MouseEvent e) {

}

@Override

public void mouseExited(MouseEvent e) {

}

@Override

public void mouseDragged(MouseEvent e) {

// Implement this function

}

@Override

public void mouseMoved(MouseEvent e) {

}

}

class DrawPanel extends JPanel{

int mRows;

int mCols;

int mGridSz;

int maxGridSz;

ArrayList mFish;

public DrawPanel(int numberOfRows, int numberOfCols, int gridSz){

mGridSz = gridSz;

mRows = numberOfRows;

mCols = numberOfCols;

maxGridSz = mGridSz * mRows;

}

private void paintBackground(Graphics g){

for (int i = 1; i

g.drawLine(i * mGridSz, 0, i * mGridSz, maxGridSz);

}

for (int mAnimateStatus = 1; mAnimateStatus

g.drawLine(0, mAnimateStatus * mGridSz, maxGridSz, mAnimateStatus * mGridSz);

}

}

@Override

public void paintComponent(Graphics g){

super.paintComponent(g);

paintBackground(g);

for (Fish f:GlobalVariables.getInstance().mFish){

f.paint(g);

}

}

public void paint(){

repaint();

}

}

Rubric