Project 1 Solution

Description

The first programming project involves writing a program that parses, using recursive descent, a GUI definition language defined in an input file and generates the GUI that it defines. The grammar for this language is defined below:

gui ::=

Window STRING ‘(‘ NUMBER ‘,’ NUMBER ‘)’ layout widgets End ‘.’ layout ::=

Layout layout_type ‘:’

layout_type ::=

Flow |

Grid ‘(‘ NUMBER ‘,’ NUMBER [‘,’ NUMBER ‘,’ NUMBER] ‘)’ widgets ::=

widget widgets |

widget

widget ::=

Button STRING ‘;’ |

Group radio_buttons End ‘;’ |

Label STRING ‘;’ |

Panel layout widgets End ‘;’ |

Textfield NUMBER ‘;’

radio_buttons ::=

radio_button radio_buttons |

radio_button

radio_button ::=

Radio STRING ‘;’

In the above grammar, the red symbols are nonterminals, the blue symbols are tokens and the black punctuation symbols are BNF metasymbols. Among the tokens those in title case are keywords. The character literals are punctuation tokens.

Below is an explanation of the meaning of some of the symbols in the above productions that should help you understand the actions that are to be performed when each of the productions is parsed:

In the window production the string is the name that is to appear in the top border of the window and the two numbers are the width and height of the window

In the production for layout_type that define the grid layout, the first two numbers represent the number of rows and columns, and the optional next two the horizontal and vertical gaps

In the production for widget that defines a button, the string is the name of the button

In the production for widget that defines a label, the string is text that is to be placed in the label In the production for widget that defines a text field, the number is the width of the text field

In the production for radio_button, the string is the label of the button

You parser should properly handle the fact that panels can be nested in other panels. Recursive productions must be implemented using recursion. Syntactically incorrect input files should detect and report the first error.

Below is an example of an input file:

Window “Calculator” (200, 200) Layout Flow:

Textfield 20;

Panel Layout Grid(4, 3, 5, 5):

Button “7”;

Button “8”;

Button “9”;

Button “4”;

Button “5”;

Button “6”;

Button “1”;

Button “2”;

Button “3”;

Label “”;

Button “0”;

End;

End.

The above input file should produce the GUI shown below:

Deliverables:

Deliverables for this project include the following:

1. Source code correctly implementing all required functionality.

2. Word or PDF file providing screen shots of successfully compiling and executing the program.

3. Description of the process and lesson learned while completing this project (to be included in the Word or PDF document).

4. A test plan that contains test cases that include both layout types, all widgets and nested panels. For each test case, the input file should be shown together with the resulting GUI. (to be included in the Word or PDF document).

2

Grading rubric:

Attribute	Meets	Does not meet
Functionality	40 points	0 points
	Writes a program that parses an	Does not writes a program that parses
	input file defining a GUI definition	an input file defining a GUI definition
	language using recursive descent.	language using recursive descent.
	Properly handles the fact that	Does not properly handle the fact that
	panels can be nested in other	panels can be nested in other panels.
	panels.
		Does not implement recursive
	Implements recursive productions	productions using recursion.
	using recursion.

Input	20 points	0 points
	Syntactically incorrect input files	Syntactically incorrect input files do
	should detect and report the first	not detect and report the first error.
	error.

Output	20 points	0 points
	Generates the GUI that the input	Does not generate the GUI that the
	file defines.	input file defines.
Documentation and	20 points	0 points
submissions	Includes source code correctly	Does not Include source code
	implementing all required	correctly implementing all required
	functionality.	functionality.
	Includes Word or PDF file providing	Does not include Word or PDF file
	screen shots of successfully	providing screen shots of successfully
	compiling and executing the	compiling and executing the program.
	program.
		Does not include a description of the
	Includes a description of the	process and lesson learned while
	process and lesson learned while	completing this project (to be included
	completing this project (to be	in the Word or PDF document).
	included in the Word or PDF
	document).
		3

	Includes a test plan that contains	Does not include a test plan that
	test cases that include both layout	contains test cases that include both
	types, all widgets and nested	layout types, all widgets and nested
	panels. For each test case, the	panels. For each test case, the input
	input file should be shown together	file should be shown together with the
	with the resulting GUI. (to be	resulting GUI. (to be included in the
	included in the Word or PDF	Word or PDF document).
	document).

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