Solution

*** How to run. ***

!!! Tested on win 10 console !!!

Just copy Java_Drawing_APP.jar to some folder on your pc. Open console and type: java -jar path_to/Java_Drawing_APP.jar Then type h - to open help in console or follow instructions tips in console.

*** Draft architecture description. ***

Design patterns that was used:

Singleton - Canvas creation. Only one canvas object can exist during user session. Command - To encapsulate drawing, quit, help etc command and decouple them from main app logic. For future if you want to add other command. You just create a new one of command folder and add it description to DrawingActions

Strategy - DrawingActions uses this pattern to connect command and their execution with main app logic. Additional benefit - avoid using switch with lot of cases or long if else tree.

AbstractFactory - Added for future. Help us to separate different GUI. In our case we use console as output. Factory will allow easy to add MacGui or WidGui as output.

entities folder - Added for moving from x, y to more concrete DAO in drawing - not implemented yet.

errors, exceptions, messages - partly supported.

utils - partly supported command parsing and validation.

Java_drawing_app

*** The Problem ***

Description

You're given the task of writing a simple console version of a drawing program. At this time, the functionality of the program is quire limited but this might change in the future. In a nutshell, the program should work as follows:

1. Create a new canvas
2. Start drawing on the canvas by issuing various commands
3. Quit

commands.Command Description C w h Should create a new canvas of width w and height h. L x1 y1 x2 y2 Should create a new line from (x1,y1) to (x2,y2). Currently only horizontal or vertical lines are supported. Horizontal and vertical lines will be drawn using the 'x' character. R x1 y1 x2 y2 Should create a new rectangle, whose upper left corner is (x1,y1) and lower right corner is (x2,y2). Horizontal and vertical lines will be drawn using the 'x' character. B x y c Should fill the entire area connected to (x,y) with "colour" c. The behaviour of this is the same as that of the "bucket fill" tool in paint programs. Q Should quit the program.

Sample I/O

Below is a sample run of the program. User input is prefixed with enter command:

enter command: C 20 4

| | | | | | | |

enter command: L 1 2 6 2

| | |xxxxxx | | | | |

enter command: L 6 3 6 4

| | |xxxxxx | | x | | x |

enter command: R 14 1 18 3

| xxxxx | |xxxxxx x x | | x xxxxx | | x |

enter command: ----------------------B 10 3 o |oooooooooooooxxxxxoo| |xxxxxxooooooox xoo| | xoooooooxxxxxoo| | xoooooooooooooo|

enter command: Q