$20
The program of part2 is designed to graphically represent the behavior of the bird. We have the four different types of birds in different color. A red color bird will move its position upward on the y-axis. A magenta color bird is moving randomly in the range of (0,0) to (19,19). A blue color bird will move zigzag through out the x-axis. When they hit the edge, they turn around and move again. A black color bird will move counter-clockwise circle. With the client program of Aviary, we set up the the program with interfaces and abstract classes. I made the AbstractBird abstract because some of the methods of my interfaces are the same for all birds. I put some fields into AbstractBird such as colors and positions are common to all birds