Take Home Exam: Design Pattern SWE423

The Java program shown in the next pages is implemented with respect to Composite design pattern. You are asked to respond to the following questions:

1. Identify the composite class,
2. Identify the Base component class,
3. Identify the components classes,
4. Draw the class diagram that fits with the program presented in the next pages.

package refactoring_guru.composite.example.shapes;

import java.awt.*;

public interface Shape {

int getX(); int getY();

int getwidth(); int getHeight);

void move(int x, int y);

boolean isInsideBounds(int x, int y);

void select);

void unSelect();

boolean isSelected);

void paint(Graphics graphics);

}

package refactoring_guru.composite.example.shapes;

import java.awt.*;

abstract class BaseShape implements Shape {

public int x;

public int y;

public Color color;

private boolean selected = false;

BaseShape(int x, int y, Color color) {

this.x = x;

this.y = y;

this.color = color;

}

@Override

public int getX() {

return x;

}

@Override

public int getY() {

return y;

@Override

public int getwidth() {

return 0;

}

@Override

public int getHeight() {

return 0;

}

@Override

public void move(int x, int y) {

this.x += x;

this.y += y;

@Override

public boolean isInsideBounds(int x, int y) {

return x > getX() &8 x

y > getY() ss y

}

@Override

public void select() {

selected = true;

override

public void unSelect() {

selected = false;

@Override

public boolean isSelected() {

return selected;

void enableSelectionStyle(Graphics graphics) {

graphics.setColor(Color.LIGHT_GRAY);

Graphics2D g2 = (Graphics2D) graphics;

float [] dash1 = {2.0f};

g2.setStroke(new BasicStroke(1.0f, BasicStroke.CAP_BUTT,

BasicStroke.JOIN_MITER,

2.0f, dash1, 0.0f));

void disableSelectionStyle(Graphics graphics) {

graphics.setColor(color);

Graphics2D g2 = (Graphics2D) graphics;

g2.setStroke(new BasicStroke());

}

@Override

public void paint(Graphics graphics) {

if (isSelected()) 3

enableSelectionStyle (graphics) ;

else

disableSelectionStyle(graphics);

}

package refactoring_guru.composite.example.shapes;

import java.awt.*;

public class Dot extends Baseshape {

private final int DOT_SIZE = 3;

public Dot(int x, int y, Color color) {

super (x, y, color);

}

@Override

public int getwidth) {

return DOT_SIZE;

}

@Override

public int getHeight() {

return DOT_SIZE;

}

@Override

public void paint (Graphics graphics) {

super.paint (graphics);

graphics.fillRect(x - 1, y - 1, getWidth(), getHeight());

Si shapes/Circle.java: A circle

package refactoring_guru. composite.example.shapes;

import java.awt.*;

public class Circle extends BaseShape {

public int radius;

public Circle(int x, int y, int radius, Color color) {

super (x, y, color);

this.radius = radius;

@Override

public int getwidth() {

return radius * 2;

}

@Override

public int getheight() {

return radius * 2;

}

public void paint (Graphics graphics) {

super.paint (graphics);

graphics.drawOval(x, y, getWidth() - 1, getHeight() - 1);

}

shapes/Rectangle.java: A rectangle

package refactoring_guru.composite.example.shapes;

import java.awt.*;

public class Rectangle extends BaseShape {

public int width;

public int height;

public Rectangle(int x, int y, int width, int height, Color color) {

super (x, y, color);

this.width = width;

this.height = height;

}

@Override

public int getwidth() {

return width;

}

@Override

public int getheight() {

return height;

}

Override

public void paint (Graphics graphics) {

super.paint (graphics);

graphics.drawRect(x, y, getwidth() - 1, getHeight() - 1);

wishapes/CompoundShape.java: Compound shape, which consists of other shape objects

package refactoring_guru.composite.example.shapes;

import java.awt.*:

import java.util.Arraylist;

import java.util.Arrays;

import java.util.List;

public class CompoundShape extends BaseShape {

protected List children = new ArrayList();

public CompoundShape(Shape... components) {

super(0, 0, Color.BLACK);

add( components);

public void add(Shape component) {

children.add(component) ;

}

public void add(Shape... components) {

children.addAll(Arrays.asList(components));

public void remove(Shape child) {

children.remove(child);

public void remove(Shape... components) {

children.removeAll (Arrays.asList (components));

}

public void clear) {

children.clear;

@Override

public int get() {

if (children.size() == 0) {

return 0;

}

int x = children.get(0). getX();

for (Shape child : children) {

if (child.getX()

x = child.getX();

return x;

}

@Override

public int getY() {

if (children.size() == 0) {

return 0;

}

int y = children.get(0). getY();

for (Shape child : children) {

if (child.getY()

y = child.getY();

}

return y;

}

@Override

public int getwidth() {

int maxwidth = 0;

int x = getX() ;

for (Shape child : children) {

int childsRelativeX = child.getX() - x;

int childwidth = childsRelativeX + child.getwidth();

if (childwidth > maxwidth) {

maxWidth = childWidth;

return maxWidth;

}

@Override

public int getHeight() {

int maxHeight = 0;

int y = getY();

for (Shape child : children) {

int childsRelativeY = child.getY) - y;

int childheight = childsRelativeY + child.getHeight();

if (childheight > maxHeight) {

maxHeight = childHeight;

return maxHeight;

}

@Override

public void move(int x, int y) {

for (Shape child: children) {

child.move(x, y);

}

@Override

public boolean isInsideBounds(int x, int y) {

for (Shape child : children) {

if (child.isInsideBounds(x, y)) {

return true;

}

return false;

}

@Override

public void unSelect () {

super. unSelect();

for Shape child : children)

child. unSelect ();

public boolean selectChildAt(int x, int y) {

for (Shape child : children) {

if (child.isInsideBounds(x, y)) {

child.select();

return true;

return false;

dOverride

public void paint (Graphics graphics) {

if (isSelected( )) {

enableSelectionStyle(graphics);

graphics.drawRect(getX() - 1, getY() - 1, getwidth() + 1, getHeight() + 1);

disableSelectionStyle(graphics);

for (Shape child : children) {

child.paint(graphics);

The Java program shown in the next pages is implemented with respect to Composite design pattern. You are asked to respond to the following questions: 1. Identify the composite class, 2. Identify the Base component class, 3. Identify the components classes, 4. Draw the class diagram that fits with the program presented in the next pages