Java类的定义

Java类的定义

package java.lancs ;



import java.awt.* ;
import java.awt.event.* ;


class BasicShape
{
// name of the shape - RECTANGLE, OVAL, etc.
int shape ;
// dimensions of the shape
int x, y, w, h ;
// colour of the shape
Color colour ;

// constructor to initialise the variables to default values
public BasicShape()
{
shape = -1 ;
x = -1 ;
y = -1 ;
w = -1 ;
h = -1 ;
colour = Color.green ;
} // end of constructor method

// constructor to initialise the variables to specifier values
public BasicShape(int sh, int x1, int y1, int w1, int h1, Color col)
{
shape = sh ;
x = x1 ;
y = y1 ;
w = w1 ;
h = h1 ;
colour = col ;
} // end of constructor method
} // end of class BasicShape


class BasicCanvas extends Canvas
{
BasicGraphics parent ;

// constructor method
public BasicCanvas(BasicGraphics p)
{
parent = p ;
} // end of constructor method

// called when class is initialised to put window on the screen
// or when window needs to be redrawn
public void paint(Graphics g)
{
Dimension d = getSize() ;
int cx = d.width / 2,
cy = d.height /2 ;
g.setColor(Color.black) ;
g.drawRect(1, 1, d.width - 3, d.height - 3) ;
int yy = 25 ;
while (yy < d.height)
{
if (yy % 100 == 0)
{
g.drawLine(1, yy, 11, yy) ;
g.drawLine(d.width - 13, yy, d.width - 3, yy) ;
}
else
{
g.drawLine(1, yy, 6, yy) ;
g.drawLine(d.width - 8, yy, d.width - 3, yy) ;
}
yy += 25 ;
}
int xx = 25 ;
while (xx < d.width)
{
if (xx % 100 == 0)
{
g.drawLine(xx, 1, xx, 11) ;
g.drawLine(xx, d.height - 13, xx, d.height - 3) ;
}
else
{
g.drawLine(xx, 1, xx, 6) ;
g.drawLine(xx, d.height - 8, xx, d.height - 3) ;
}
xx += 25 ;
}

for (int i = 0 ; i < parent.noOfShapes ; i++)
{
g.setColor(parent.shapeList[i].colour) ;

if (parent.shapeList[i].shape == BasicGraphics.RECTANGLE)
{
g.drawRect(parent.shapeList[i].x, parent.shapeList[i].y,
parent.shapeList[i].w, parent.shapeList[i].h) ;
}
else if (parent.shapeList[i].shape == BasicGraphics.FILLED_RECTANGLE)
{
g.fillRect(parent.shapeList[i].x, parent.shapeList[i].y,
parent.shapeList[i].w, parent.shapeList[i].h) ;
}
else if (parent.shapeList[i].shape == BasicGraphics.OVAL)
{
g.drawOval(parent.shapeList[i].x, parent.shapeList[i].y,
parent.shapeList[i].w, parent.shapeList[i].h) ;
}
else if (parent.shapeList[i].shape == BasicGraphics.FILLED_OVAL)
{
g.fillOval(parent.shapeList[i].x, parent.shapeList[i].y,
parent.shapeList[i].w, parent.shapeList[i].h) ;
}
else if ((parent.shapeList[i].shape == BasicGraphics.TRIANGLE) ||
(parent.shapeList[i].shape == BasicGraphics.FILLED_TRIANGLE))
{
int x1 = parent.shapeList[i].x ;
int y1 = parent.shapeList[i].y ;
int w1 = parent.shapeList[i].w ;
int h1 = parent.shapeList[i].h ;

Polygon p = new Polygon() ;
p.addPoint(x1, y1 + h1) ;
p.addPoint(x1 + w1, y1 + h1) ;
p.addPoint(x1 + (w1 / 2), y1) ;
p.addPoint(x1, y1 + h1) ;

if (parent.shapeList[i].shape == BasicGraphics.TRIANGLE)
g.drawPolygon(p) ;
else
g.fillPolygon(p) ;
}
}
} // end of method paint

} // end of class BasicCanvas


public class BasicGraphics extends Frame implements ActionListener
{
// maximum width of window
private static final int MAX_WIDTH = 600 ;

// maximum height of window
private static final int MAX_HEIGHT = 400 ;


public static final int RECTANGLE = 1 ;


public static final int OVAL = 2 ;


public static final int TRIANGLE = 3 ;


public static final int FILLED_RECTANGLE = 4 ;


public static final int FILLED_OVAL = 5 ;


public static final int FILLED_TRIANGLE = 6 ;

BasicShape[] shapeList = new BasicShape[50];

int noOfShapes = 0;

private BasicShape newShape = new BasicShape();

private Button quit ;


public BasicGraphics()
{
setTitle("BasicGraphics Window") ;
setSize(MAX_WIDTH, MAX_HEIGHT + 50) ;

BasicCanvas c = new BasicCanvas(this) ;
add("Center", c) ;

Panel p = new Panel() ;
p.setLayout(new FlowLayout()) ;
quit = new Button("Quit") ;
p.add(quit) ;
quit.addActionListener(this) ;
add("South", p) ;
} // end of constructor method


public void actionPerformed(ActionEvent event)
{
dispose() ;
System.exit(0) ;
} // end of method actionPerformed


public void setShape(int shape)
{
if ((shape != RECTANGLE) && (shape != FILLED_RECTANGLE) &&
(shape != OVAL) && (shape != FILLED_OVAL) &&
(shape != TRIANGLE) && (shape != FILLED_TRIANGLE))
{
System.err.println("This is not a valid shape");
System.exit(1);
}
newShape.shape = shape ;
} // end of method setShape


public void setDimensions(int x, int y, int w, int h)
{
if (newShape.shape == -1)
{
System.err.println("You need to set the shape first");
System.exit(1);
}
if ((x < 5) || (y < 5) || (w < 5) || (h < 5) ||
(x + w > MAX_WIDTH - 5) || (y + h > MAX_HEIGHT - 5))
{
System.err.println("Invalid dimensions supplied") ;
System.exit(1);
}
newShape.x = x ;
newShape.y = y ;
newShape.w = w ;
newShape.h = h ;
} // end of method setDimensions


public void setColour(Color colour)
{
if (newShape.x == -1)
{
System.err.println("You need to set the dimensions first");
System.exit(1);
}
newShape.colour = colour ;
shapeList[noOfShapes] = new BasicShape(newShape.shape,
newShape.x, newShape.y,
newShape.w, newShape.h,
newShape.colour) ;
noOfShapes++ ;
newShape = new BasicShape() ;
} // end of method setColour


public void draw()
{
setVisible(true) ;
} // end of method draw

} // end of class BasicGraphics

class a{
private l int ; //长
private w int ; //宽
public int getValue(int l,int w)
{
return l*w; //计算其面积
}
}
……晕不想写来。这个是作业题。帮你写了 太不道德了，