Design Patterns Explained

Example 9-3 Java Code Fragments (continued)
}
drawLine(_x2,_y2,_x1,_y2);
drawLine(_x1,_y2,_x1,_y1);
}
class Circle extends Shape {
public Circle (
Drawing dp,
double x,double y,double r) {
super( dp) ;
_x= x; _y= y; _r= r ;
}
}
public void draw () {
drawCircle(_x,_y,_r);
}
// We’ve been given the implementations for DP1 and DP2
class DP1 {
static public void draw_a_line (
double x1,double y1,
double x2,double y2) {
// implementation
}
static public void draw_a_circle(
double x,double y,double r) {
// implementation
}
}
class DP2 {
static public void drawline (
double x1,double x2,
double y1,double y2) {
// implementation
}
static public void drawcircle (
double x,double y,double r) {
// implementation
}
}
Chapter 9 The Bridge Pattern 149