Description
1. Specification
The fourth programming project involves designing, writing and testing a program that behaves like the Java
command line compiler. Whenever we request that the Java compiler recompile a particular class, it not only
recompiles that class but every other class that depends upon it, directly or indirectly, and in a particular order.
To make the determination about which classes need recompilation, the Java compiler maintains a directed
graph of class dependencies. Any relationship in a UML class diagram of a Java program such as inheritance
relationships, composition relationships and aggregations relationships indicate a class dependency.
The main class P4GUI should create the Swing based GUI shown below:
The GUI must be generated by code that you write. You may not use a drag-and-drop GUI generator.
Pressing the Build Directed Graph button should cause the specified input file that contains the class
dependency information to be read in and the directed graph represented by those dependencies to be built.
The input file should be generated by the students using a simple text editor such as Notepad. The input file
associated with the above example is shown below:
ClassA ClassC ClassE
ClassB ClassD ClassG
ClassE ClassB ClassF ClassH
ClassI ClassC
Each line of this file specifies classes that have other classes that depend upon them. The first line, for example,
indicates that ClassA has two classes that depend upon it, ClassC and ClassE. In the context of
recompilation, it means when ClassA is recompiled, ClassC and ClassE must be recompiled as well. Using
graph terminology, the first name on each line is the name of a vertex and the remaining are its associated
adjacency list. Classes that have no dependent classes need not appear at the beginning of a separate line.
Notice, for example, that ClassC is not the first name on any line of the file.
After pressing the Build Directed Graph button, one of following two messages should be generated depending
upon whether the specified file name could be opened:
Once the graph has been built, the name of a class to be recompiled can be specified and the
Topological Order button can be pressed. Provided a valid class name has been supplied, a topological order
algorithm should be executed that will generate (in the text area at the bottom of the GUI window) the list of
classes in the order they are to be recompiled. The correct recompilation order is any topological order of the
subgraph that emanates from the specified vertex.
An invalid class name should generate an exception and an appropriate error message will be displayed in a
JOptionPane. If the graph contains a cycle among the Java classes, an exception will be thrown and a message
will be displayed in a JOptionPane indicating that a cycle has been detected.
Note. In the real compiling processes, when circular dependencies exist in Java programs, the compiler must
make two passes over all the classes in the cycle. For this program, it will be sufficient to display a message
indicating that a cycle has been detected.
In addition to the main class that defines the GUI, a second class is needed to define the directed graph. It
should be a generic class allowing for a generic type of its vertices. In this application the type of the vertices
will be String.
For better processing purposes, integer values will be used to represent the vertices instead of Strings. The
graph should be represented as an array list of vertices (as integer values) that contain a linked list of their
associated adjacency lists. The adjacency lists should be lists of integers that represent the index rather than
vertex name itself. A hash map should be used to associate vertex names with their index in the list of vertices.
For the input file shown above the array list of linked lists of integers would be the following:
0 [1, 2]
1 []
2 [3, 6, 7]
3 [4, 5]
4 []
5 []
6 []
7 []
8 [1]
Storing the vertex indices rather than the names simplifies the topological order algorithm. The hash map would
associate index 0 with ClassA, index 1 with ClassC, index 2 with ClassE and so on.
The directed graph class should define methods for initializing the graph each time a new file is read in, for
adding a vertex and an edge to the graph and for generating a topological order given a starting index. Other
classes / methods could be also defined to achieve the program requirements and for better structuring the
code.
Finally, custom checked exception classes should be defined for the cases where a cycle occurs and when an
invalid class name is specified.
Your program should compile without errors.
The Google recommended Java style guide (https://google.github.io/styleguide/javaguide.html) should be used
to format and document your code. Specifically, the following style guide attributes should be addressed:
header comments include filename, author, date and brief purpose of the program; In-line comments used to
describe major functionality of the code; the meaning and the role of variables and constants are indicated as
code comments; meaningful variable names and prompts applied; class names are written in UpperCamelCase;
variable names are written in lowerCamelCase; constant names are in written in All Capitals; braces use K&R
style.
In addition the following design constraints should be followed: declare all instance variables private; avoid the
duplication of code.
2. Submission requirements
Submit the following to the Project 2 assignment area no later than the due date listed in your LEO classroom.
1. All .java source files (no other file types should be submitted). The source code should use Java code
conventions and appropriate code layout (white space management and indents) and comments. All submitted
files may be included in a .zip file.
2. The solution description document P3SolutionDescription (.pdf or .doc / .docx) containing the following:
(1) Assumptions, main design decisions, error handling;
(2) A UML class diagram that includes all classes you wrote. Do not include predefined classes. You need only
include the class name for each individual class, not the variables or methods;
(3) A table of test cases including the test cases that you have created to test the program. The table has 5
columns indicating (i) what aspect is tested, (ii) the input values, (iii) the expected output, (iv) the actual output
and (v) if the test case passed or failed. Each test case will be defined in a table row.
(4) Relevant screenshots of program execution;
(5) Lessons learned from the project;
Grading Rubric:
Criteria Meets Does Not Meet
Design
5 points 0 points
GUI is hand coded and matches required
design
GUI is generated by a GUI generator or
does not match required design
Includes generic class for a directed graph Does not include a generic class a directed
graph
Graph is represented as an array list of
vertices that contain a linked list of their
associated adjacency lists
Graph is not represented as an array list
of vertices that contain a linked list of
their associated adjacency lists
Includes checked exception classes for cycles
and invalid class names
Does not Include checked exception
classes for cycles and invalid class names
Uses good object-oriented design practice
regarding code efficiency, encapsulation and
information hiding, class and code reuse,
high cohesion of classes, avoiding code
duplication.
Does not use good object-oriented design
practice regarding code efficiency,
encapsulation and information hiding,
class and code reuse, high cohesion of
classes, avoiding code duplication.
Functionality
10 points 0 points
Produces correct topological order for all
cases without cycles
Does not produce correct topological
order for all cases without cycles
Produces error message for all cases with
cycles
Does not produce error message for all
cases with cycles
Reports error message when file does not
open
Does not report error message when file
does not open
Reports error message when invalid class
name is entered
Does not report error message when
invalid class name is entered
Generates message confirming graph has
been built
Does not generate message confirming
graph has been built
5 points 0 points
Test cases table is defined and included in
the P4SolutionDescription document
Test cases table is not defined and
included in the P4SolutionDescription
document
Test cases include a graph without cycles Test cases do not include a graph without
Test Cases cycles
Test cases include a graph with cycles Test cases does not include a graph with
cycles
Test cases include an invalid file name Test cases do not include an invalid file
name
Test cases include an invalid class name Test cases do not include an invalid class
name
Documentation
5 points 0 points
Solution description document
P4SolutionDescription includes all the
required sections (appropriate titled).
No solution description document is
included
Source code follows Google
recommendation Java style
Source code does not follow Google
recommendation Java style
Comment blocks with class description
included with each class
Comment blocks with class description
not included with each class
Source code is commented and indented Source code is not commented and
indented
Overall Score Meets Does not meet
16 or more 15 or less
