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package horstmann.ch07_serial2;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.geom.Ellipse2D;
import java.awt.geom.RectangularShape;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
/**
A serializable car shape.
*/
public class Car implements Serializable
{
private static final long serialVersionUID = 2008L;
/**
Constructs a car.
@param x the left of the bounding rectangle
@param y the top of the bounding rectangle
@param width the width of the bounding rectangle
*/
public Car(int x, int y, int width)
{
body = new Rectangle(x, y + width / 6,
width - 1, width / 6);
roof = new Rectangle(x + width / 3, y,
width / 3, width / 6);
frontTire = new Ellipse2D.Double(x + width / 6, y + width / 3,
width / 6, width / 6);
rearTire = new Ellipse2D.Double(x + width * 2 / 3, y + width / 3,
width / 6, width / 6);
}
private void writeObject(ObjectOutputStream out)
throws IOException
{
out.defaultWriteObject();
writeRectangularShape(out, frontTire);
writeRectangularShape(out, rearTire);
}
/**
A helper method to write a rectangular shape.
@param out the stream onto which to write the shape
@param s the shape to write
*/
private static void writeRectangularShape(ObjectOutputStream out,
RectangularShape s)
throws IOException
{
out.writeDouble(s.getX());
out.writeDouble(s.getY());
out.writeDouble(s.getWidth());
out.writeDouble(s.getHeight());
}
private void readObject(ObjectInputStream in)
throws IOException, ClassNotFoundException
{
in.defaultReadObject();
frontTire = new Ellipse2D.Double();
readRectangularShape(in, frontTire);
rearTire = new Ellipse2D.Double();
readRectangularShape(in, rearTire);
}
/**
A helper method to read a rectangular shape.
@param in the stream from which to read the shape
@param s the shape to read. The method sets the frame
of this rectangular shape.
*/
private static void readRectangularShape(ObjectInputStream in,
RectangularShape s)
throws IOException
{
double x = in.readDouble();
double y = in.readDouble();
double width = in.readDouble();
double height = in.readDouble();
s.setFrame(x, y, width, height);
}
/**
Draws the car.
@param g2 the graphics context
*/
public void draw(Graphics2D g2)
{
g2.draw(body);
g2.draw(roof);
g2.draw(frontTire);
g2.draw(rearTire);
}
public String toString()
{
return getClass().getName()
+ "[body=" + body
+ ",roof=" + roof
+ ",frontTire=" + formatRectangularShape(frontTire)
+ ",rearTire=" + formatRectangularShape(rearTire)
+ "]";
}
/**
A helper method to format a rectangular shape.
@param s the shape to format
@return a formatted representation of the given shape
*/
private static String formatRectangularShape(RectangularShape s)
{
return RectangularShape.class.getName()
+ "[x=" + s.getX()
+ ",y=" + s.getY()
+ ",width=" + s.getWidth()
+ ",height=" + s.getHeight()
+ "]";
}
private Rectangle body;
private Rectangle roof;
private transient Ellipse2D.Double frontTire;
private transient Ellipse2D.Double rearTire;
}
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