Before I dive into the points, let me just give a quick backgrounder on what Agile Software Development is. Notice I didn’t mention any specific methodology, and this is because being Agile is more a state of mind than a rigid set of practices — if anybody tells you otherwise, they might be misunderstanding the Agile Manifesto.

Manifesto for Agile Software Development

We are uncovering better ways of developing software by doing it and helping others do it. Through this work we have come to value:

Individuals and interactions over processes and tools

Working software over comprehensive documentation

Customer collaboration over contract negotiation

Responding to change over following a plan
That is, while there is value in the items on the right, we value the items on the left more.

– Agile Manifesto

So what are the hallmarks of Agile Software Development? For one thing, the premium on:

• Iterative Development — building software in a way that allows for quickly changing implementations over a period of time, and making sure that something gets delivered and iterated on.
• Testing — having tests to ensure that components of the system (and the system as a whole) works as specified.
• Welcoming Changes — instead of having lengthy planning, the solution is built to assume that anything at any given point later on can (and probably will) change.

In the world of dynamic languages and object-oriented systems, is there a place for Agile development with C++? Well, of course the answer is yes!

Because Agile Software Development is a process or a “way of building software”, the tools you use aren’t largely affected — but the practices you follow might be affected. For example, instead of writing lengthy design documents, you’d rather write code and generate the design document out of the code; instead of writing specification documents, you actually write unit/integration/system-level/acceptance tests; instead of having planning sessions you have quick 5-minute meetings and more collaborative modes of development (pair-programming, for example). Now other languages have tons of tools that help with making these practices more in-grained in the development process — things like one-click unit-test runners and continuous testing environments (that build and run the tests as soon as changes are being made to the code for immediate feedback).

I for one have been following different practices in the various Agile C++ projects I’ve been involved in.

• Test Driven Development — In any software I write now, I feel like fish out of water if I don’t write the tests first to define what I require from the component I’m writing. Having tests to verify both your specifications and implementation are actually sufficient saves you from the guesswork you otherwise have to go through when developing software. Having a deterministic and honest — even automated — way of making sure you’re understanding the specifications and implementing something acceptable is definitely the way to go in case you intend to make changes along the way.
• Active Code Review — In all the previous software projects I’ve been involved in, there is no sacred code and everything is subject to review (and improvement). This makes people care about the code they write and the design decisions they’re making. It also ensures that everybody is made involved in the process of developing and learning from the code that’s being developed.
• Pair Programming — I swear by the productivity improvement of pairing developers up to work on the same part of the system. The additional support and guidance you get from an additional set of eyes really affects the way I write code and the way I approach problems. The best part about pair programming is not the part where you’re writing code, but the part when you’re talking out the approach and the design decisions before writing — or while writing — any code.
• Brutal Retrospective — It’s important to stay honest when coding to see where the faults and issues are and be able to say what these are and how they should be addressed. There’s no point in sugar-coating the state of affairs especially when the success of a project is at stake. In other words, call it as you see it, and learn from the experience by making changes along the way.
• Measure Progress and Productivity — It’s great to be able to measure the actual productivity of a team and be able to adjust as you go along in the project. There are a lot of ways in which progress and productivity are measured, but the details don’t matter as much as the fact that measuring it matters. Do it however you like, but just make sure you’re measuring progress and productivity.

Overall I’ve been in various roles in the Agile projects I’ve worked with in the past. Having a clear understanding of what your software needs to do and what the customer wants is key to the Agile process. The clarity yields happier customers and better software in the long run, and even improves developer productivity by being able to focus and iterate on the solution rather than trying to design it right at the start.

So have you been part of an Agile Software Development project lately with C++? How did you find it? Did I miss anything obvious above?

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According to Red Hat’s page on this new certification, RHCSA was based on a curriculum built around surveying current Red Hat certified professionals. These surveys, coupled with focus groups at various Red Hat and community conferences, sought out the most commonly required tasks of Red Hat system administrators. These tasks are at the core of the new Red Hat certification. The Red Hat Certified Technician certification is the low-level certification offered by Red Hat. Research by Red Hat found that these "Technicians" were really just system administrators, and wanted to reflect the difference in this new certification. The RHCSA certification is similar to that of the RHCT, but also includes additional competencies from the Red Hat Certified Engineer (RHCE) certification. A hands-on lab test is also part of the Red Hart Certified System Administrator certification.

Red Hat summarizes their changes to their Linux Curriculum in three points. First, the Red Hat curriculum was restructured to provide clear paths for various IT Professionals. Red Hat hopes to make it easier for a Windows administrator, low-level Linux administrator, or any other IT professional to find the right curriculum to meet their certification objectives. Secondly, the survey mentioned above of Red Hat certified professionals used to structure the new Red Hat Certified System Administrator certification was also used to restructure the curriculum. Understanding the current demands of Red Hat professionals allowed Red Hat to more accurately and properly focus their curriculum. Lastly, the teaching method has been updated to focus more on hand-ons participation and less lecture.

For more info see:

http://press.redhat.com/2010/11/11/linux-curriculum-redesigned-to-better-align-with-todays-it-needs/

http://press.redhat.com/2010/11/11/introducing-the-red-hat-certified-system-administrator-rhcsa-certification/

Preparation and examination for a Microsoft certification is the assured method of being a genuine Microsoft solutions professional. In the fairly distant past, the most recognized and sought-after Microsoft certification was the Microsoft Certified Systems Engineer (M.C.S.E.).

Well as time has passed, Microsoft no longer offers the M.C.S.E for its newest products. The M.C.S.E. only pertains to their 2003 server product line. Microsoft offers new certifications for all of their current product lines. Newer certifications, for example, Microsoft Certified Information Technology Professional (M.C.I.T.P.), Microsoft Certified Technology Specialist (M.C.T.S.), Microsoft Certified Desktop Support Technician (M.C.D.S.T.), Microsoft Certified Systems Administrator (M.C.S.A.) and Microsoft Certified Database Administrator (M.C.D.B.A.), fulfill most of the major IT scope. Other certifications focus on niche cases.

So, while M.C.S.E has been the best known certification that Microsoft offers, many more current certifications will solidify your Microsoft products knowledge. You can work your way to becoming a Microsoft Certified Architect, or even a Microsoft Certified Master! In Microsoft’s own words: “Microsoft Certification helps validate the skills you use every day. It helps you improve your technology problem-solving skills and your performance on the job. Go ahead. Strive for the rewards, respect, and recognition you deserve. Become a Microsoft Certified Professional!”

• How to propose Drupal as a solution to meet collaboration technology platform requirements for the Open Government Directive plan
• Training and support for setting up a Drupal site at http://www.[agency].gov/open
• Planning for security and scalability of  an organization’s OGD Drupal site
• Design and implementation of Drupal sites to meet specific OGD requirements
• How to get Drupal Certification and Accreditation for Drupal for your agency

Acquia’s vice president of business development, Tim Bertrand, explains:

“Drupal has always seen great success in the government sector and now with the OGD in play, we expect that even more agencies will see the value of Social Publishing in meeting these requirements.”

Acquia will also offer a seminar series for U.S. federal, state and local governments to discuss adoptions and best practices for government use.  This is definitely a smart move as risk averse government agency IT decision makers will take comfort in the successes of their peers with Drupal Social Publishing.

Acquia appears poised to take advantage of the growing interest in open source and social media.  Increased use of Drupal will open the door further to open source usage within governments, in the U.S. and worldwide.  In doing so, Acquia is definitely playing its part as a founding member of Open Source for America.

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1.Detect garbage objects
2.Deallocate the memory of garbage objects and make it available for the program.

There are four approaches that a garbage collector may adopt to detect the garbage objects.

A) Reference -counting Collectors :-Reference counting garbage collectors keep a count of the references for the each live object.When an object is created ,the reference count of each object is set to one.When you reference the object ,the reference count is incremented by one.Similarly when a reference to an object is eliminated ,the reference count is decremented by one.An object which has reference count zero is a garbage object when the object is garbage collected ,the references of the object that it refers to are decremented.Therefore garbage collection of the one may lead to the creation of other garbage objects.This method can be executed in small parts with the program ,and the program need not to be interrupted for a long time. However ,there is an overhead of incrementing and decrementing the counter everytime something happens on the references side.

B) Tracing Collectors :-In this technique ,a set of root is defined from where objects are traced. An object is reachable if there are objects that referenced and cannot ,therefore be accessed in the program.Objects that are reachable are marked. At the end of the trace ,all marked objects can be garbage collected.
This is also known as the mark and sweep algorithm. The mark phase marks all the referenced objects. The sweep phase garbage collects the memory of unreachable and unreferenced objects.

C) Compacting Collectors :-These collectors reduce the degree of memory fragmentation by moving the all unused and free space on one side during garbage collection.The free memory is then available as one huge chunk.All references need to be shifted ,objects are the updated to refer to the new memory locations.

D)Adaptive Collectors :-This algorithm makes the use of the fact that different garbage collectors algorithm works better in different situations. The adaptive algorithm monitors the situation and uses the garbage technique that best suits the situation. It may switch from one technique to the other according to the need.

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General Syntax :-

expression 1 ? expression 2 : expression 3

Here expression 1 can be any expression that evaluates to a Boolean value.If expression 1 is true then expression 2 is evaluated else expression 3 is evaluated.Both the expressions expression 1 and expression 2 must have a return type,they can never be void.Make it more clear by understanding below example.

Example:-

public class optest
{
public static void main(String a[])
{
int ratio=0,num=20,denom=10;

/* The ” ? ” operator assignes 0 if condition denom==0 is true else it assigns num/denom to ratio if condituion is false*/

ratio=denom==0?0:num/denom;

System.out.println(“The ratio is “+ratio);
}
}

Output:-
The ratio is 2

Explanation:-When Java evaluates this assignment expression ,it first looks at the expression to the left of the question mark.If denom equals to zero then expression 2 between ? and : is evaluated else last expression is evaluated.The resultant is then assigned to the ratio variable used in expression 1.

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Try to answer these questions on your own but if you cannot recall the concept go refer book,any core Java book will do.

Important Core Java Questions :-

1.How many access modifiers a class can use and which are they?

2.What are the Instance variables?

3.What are local variables?

4.What is the default access modifier and how it is different from protected access modifier?

5.Can you ever mark a class as final?

6.Is it true that we can use abstract and final both on same time and same Java entity?

7.What is the IS-A and HAS-A relationship in Java?

8.What is multiple inheritance and how you can implement multiple inheritance in Java?

9.What is the size of compiler generated Java Bytecode?

10.Does Interfaces follow the Inheritance?

11.A subclass can inherit the private member of superclass is this statement true,give reason?

12.What is the bit depth of Boolean variable in Java?

13.What will happen if finally block itself generates an Exception?

14.What is exception propagation?

15.How Inheritance is affected by object serialization?

These are a few questions which I thought as Important.Further there are some references I am giving in order to solve these questions.

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1.Attempting to access an instance variable from a static context (i.e. from main() method)

Since static variable can only be accessed from static context thus there is no way you can access the non-static instance variable in static context without a reference.For example:-

Class Scopetest{
int x=10;
public static void main(String a[]){
System.out.println(x++);
}
}

This will result in an error
Scopetest.java:4: non-static variable x cannot be referenced from a static context
System.out.println(x++);

Despite this you can use the instance of Scopetest class to access the variable as shown below:-

class Scopetest{
int x=10;
public static void main(String a[]){
System.out.println(new Scopetest().x++);
}
}

This will produce output as 10.
So,remember you can never ever access a non-static instance variable within a static context alone.You have to use the enclosing class instance.

2.Attempting to use a block variable after the code block is completed.
How often we commit this error,I guess everyone of us has faced it.So remember never ever try to invoke a variable which is ended its life.That is block variable lifetime is until the code block completes.As block finished execution the variable will also perish from memory,thus any reference out of this block result in a compiler slap!!!
Lets take a look at following example:-

class Scopetest{
public static void main(String a[]){
for(i=0;i<2;i++) style=”font-style: italic;”>.java:5: cannot find symbol
symbol : variable i
location: class Scopetest
if(i<3)>

3.Attempting to access a local variable from nested method.
When a method invokes another method then the calling method does not have access to the called methods variables and vice versa.For example:-If we have a method do1() which called by another method do2() then do1() cannot access the variables local to do2().It is evident from the following example:-

class Scopetest{
public static void main(String[] a){
Scopetest s = new Scopetest();
s.do2();
}
public void do2(){
int x = 4;
do1();
++x;
}
public void do1(){
x++;
}
}

The error which appears is:-
Scopetest.java:12: cannot find symbol
symbol : variable x
location: class Scopetest
x++;

So next time you go to the battlefield(programming) keep yourself armed with better knowledge and strategies of course here is to reduce the bug and make your program more readable.Keep in mind above mentioned errors and be a good programmer,and keep firing on the COMPILER!!!.

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