How to draw a Control flow graph & Cyclometric complexity for a given procedure

Cyclomatic Complexity 

Cyclomatic complexity is a software metric used to measure the complexity of a program.

These metric, measures independent paths through program source code.Independent path is defined as a path  that has at least one edge which has  not been traversed before in any other paths.

Cyclomatic complexity can be calculated with respect to functions, modules, methods or classes within a program.

Cyclomatic Flow

Compound Condition 

where one or more Boolean operators such as logical OR, AND, NAND, NOR are present is a conditional statement

IF a OR b
then procedure x
else procedure y

A predicate node will be created for each statement.
Compound Logic

Check the following code fragment

insertion_procedure (int a[], int p [], int N)
    int i,j,k;
    for (i=0; i<=N; i++) p[i] = i;
    for (i=2; i<=N; i++)
        k = p[i];
        j = 1;
        while (a[p[j-1]] > a[k]) {p[j] = p[j-1]; j--}
        p[j] = k;
  • first and foremost start numbering the statement
insertion_procedure (int a[], int p [], int N)
(1)    Int i,j,k;
(2)    for ((2a)i=0; (2b)i<=N; (2c)i++) 
(3)        p[i] = i;
(4)    for ((4a)i=2; (4b)i<=N; (4c)i++)
(5)       k=p[i];j=1;
(6)       while (a[p[j-1]] > a[k]) {
(7)           p[j] = p[j-1]; 
(8)           j--
(9)          p[j] = k;
  • Now you can clearly see which statement executes first and which last etc. so drawing the CFG becomes simple.

Now, to calculate cyclomatic complexity you use one of three methods

  1. Count the number of regions on the graph: 4
  2. No. of predicates (red on graph) + 1 : 3 + 1 = 4
  3. No of edges – no. of nodes + 2: 14 – 12 + 2 = 4

That’s about it , Happy Coding 🙂

From women’s eyes this doctrine I derive
They sparkle still the right Promethean fire
They are the books, the arts, the academies
That show, contain and nourish all the world

– William Shakespeare

Love’s Labour’s Lost

Creating a Simple Maven Project in eclipse (m2eclipse)

First and foremost you have to install maven  plugin to eclipse  by going through it’s own marketplace , Integrated link will guide you how to integrate Maven in to your Eclipse IDE  .

One of the most compelling features of m2eclipse is the ability to quickly generate new Maven projects using the New Maven project wizard. This post and the associated video demonstrate the steps to create a simple Maven project using the New Maven project wizard to select the Maven Quick start archetype.

To create a simple project using the New Maven project wizard

  1. Select File – New Project. This should display the New Project dialog.
  2.  In the New Project Dialog, expand the Maven folder, and select Maven Project.
  3. Click Next. The next screen provides options for customizing the location of your new Maven project. If you are storing the new project in your work space, you can supply the directory on this page.
  4. Click Next. The next screen lists all of the available Maven Archetypes, select the Maven Quick start Archetype which should be listed under the group id org.apache.maven.archetypes.
  5. Click Next. On the next screen, supply a Group Id, Artifact Id, and Version for your new project.

Click Finish and m2eclipse will use the Maven Quick start Archetype to generate a new Maven project in your Eclipse work space.

Beginners Maven guide video tutorials on Youtube

Don’t bother with archetypes until later

For all information you need to know about Maven, have a read of “Better Builds with Maven” (PDF). However, that’s a bit of overkill for what you’re trying to achieve.

To get started, lay out your web application following the standard Maven structure for web apps as follows. (You don’t need a Maven archetype for this, it’s just a bunch of standard folders, you can make it in 2 minutes).

  • src/main/java – contains your production Java code
  • src/main/resources – contains your production classpath resources (e.g. Spring contexts)
  • src/main/webapp – (contains WEB-INF/web.xml but no lib folder)
  • src/test/java – contains your test Java code
  • src/test/resources – contains your test resources (e.g. example XML feeds for web service testing etc)

Basic plugins

The next step is to choose a bunch of plugins. The usual suspects are, obviously the ones supporting clean, compile, and resources (come as part of Maven but you can configure them). Then you’ll have the surefire unit tester and the WAR plugin. That’s enough to create a very basic web application.

More advanced plugins

The next step is to introduce Findbugs and PMD plugins which will give your code a thorough going over and report various potential issues. You probably will want to have JXR for cross-referencing source code, taglist for tracking TODOs and REFACTOR tags and so on. Above all…

…Use the Jetty plugin for web applications

Use the Jetty plugin to run up your WAR file within your IDE for easy debugging. It’s fast and small and gets the job done real quick. Having Jetty as part of your Maven build makes your project able to be tested on any machine without needing an IDE with some complex Servers panel configured. It also allows you to declare dependencies on other WAR files which in turn means you can generate a complete working environment consisting of multiple web applications all with a single command “mvn clean jetty:run”. This works anywhere, and you can even provide a test JNDI configuration so your Spring-injected data sources are all externally configured. If you combine this Jetty approach with a standard demonstration HTML page (src/test/resources/demo.html) you’ll save oodles of developer hours trying to get a working local environment. One command and you’re done. Simple.

Configuring your IDE

With Maven it’s easy since all the big boys support it: Eclipse, Netbeans and, of course my personal favourite Intellij. Just point your IDE at the pom.xml and it’ll take care of bring down all the listed dependencies for you. No more mucking about with WEB-INF/lib. In Eclipse, you typically use File | Import… | Maven Project | pom.xml.

Integrating with Hudson

First install Hudson (it’s just a webapp) and then target your version control system so that it checks out the appropriate version. Your final step is to configure it so that it uses Maven to do the build. Obviously Maven will have to be installed on your build machine (assuming it’s different from your development machine).

Hudson does the snapshot builds only

Have Hudson perform snapshot builds, and leave release builds to a manual process. Using that approach will mean that developers can share their code under a snapshot revision (e.g. 1.0.0-SNAPSHOT) and only if it is able to pass the build will it be shared into the team repository. Typically, Hudson will execute “mvn clean deploy” although including the “site” goal may also be part of your process since it’ll create a small project website for every build. Developers on the team will have the updated snapshot build automatically included into their project through the Maven dependency management process.

Hudson provides a wealth of plugins that can support all manner of metrics. My personal favourite is to keep track of the number of passing tests per project over time. It’s great to show management that your unit test count and coverage is ever increasing.

General setup guidance

Split your repositories into at least the following structure:

  • team-release – All your released production artifacts go here
  • team-snapshot – All your snapshot development artifacts go here
  • third-party-release – All your supporting third-party libraries go here (e.g. Spring, Hibernate etc)

Developer user accounts should not be able to write to the team repositories, either snapshot or release. This would enable a developer to bypass Hudson if they’re in a hurry and will quickly become the norm.

Make sure you always download the source, javadocs and SHA signatures for all your third parties. Jarvana is an excellent repository explorer for all those hard to find classes.

Consider installing a repository manager like Nexus or Artifactory to allow better control over your ever-growing repository.

Hope this tutorial might help you to integrate Maven in to your eclipse Thank you 🙂 Happy coding

Reference link