package reuse;

class Shape {
 Shape(int i) {
 System.out.println("Shape constructor");
 }

 void dispose() {
 System.out.println("Shape dispose");
 }
}


class Circle extends Shape {
 Circle(int i) {
 super(i);
 System.out.println("Drawing Circle");
 }

 @Override
 void dispose() {
 System.out.println("Erasing Circle");
 super.dispose();
 }
}


class Triangle extends Shape {
 Triangle(int i) {
 super(i);
 System.out.println("Drawing Triangle");
 }

 @Override
 void dispose() {
 System.out.println("Erasing Triangle");
 super.dispose();
 }
}


class Line extends Shape {
 private int start, end;

 Line(int start, int end) {
 super(start);
 this.start = start;
 this.end = end;
 System.out.println("Drawing Line: " + start + ", " + end);
 }

 @Override
 void dispose() {
 System.out.println("Erasing Line: " + start + ", " + end);
 super.dispose();
 }
}


/**
 * @Author ZhangGJ
 * @Date 2020年04月29日 22:24
 */
public class CADSystem extends Shape {
 private Circle c;
 private Triangle t;
 private Line[] lines = new Line[3];

 public CADSystem(int i) {
 super(i + 1);
 for (int j = 0; j < lines.length; j++) {
 lines[j] = new Line(j, j * j);
 }
 c = new Circle(1);
 t = new Triangle(1);
 System.out.println("Combined constructor");
 }

 @Override
 public void dispose() {
 System.out.println("CADSystem.dispose()");
 // The order of cleanup is the reverse
 // of the order of initialization:
 t.dispose();
 c.dispose();
 for (int i = lines.length - 1; i >= 0; i--) {
 lines[i].dispose();
 }
 super.dispose();
 }

 public static void main(String[] args) {
 CADSystem x = new CADSystem(47);
 try {
 // Code and exception handling...
 } finally {
 x.dispose();
 }
 }
}