I will begin our blog on Java Tutorial with an incredibly important aspect of java development:  memory management.  The importance of this topic should not be minimized as an application's performance and footprint size are at stake.

From the outset, the Java Virtual Machine (JVM) manages memory via a mechanism known as Garbage Collection (GC).  The Garbage collector

• Manages the heap memory.   All obects are stored on the heap; therefore, all objects are managed.  The keyword, new, allocates the requisite memory to instantiate an object and places the newly allocated memory on the heap.  This object is marked as live until it is no longer being reference.
• Deallocates or reclaims those objects that are no longer being referened. 
• Traditionally, employs a Mark and Sweep algorithm.  In the mark phase, the collector identifies which objects are still alive.  The sweep phase identifies objects that are no longer alive.
• Deallocates the memory of objects that are not marked as live.
• Is automatically run by the JVM and not explicitely called by the Java developer.  Unlike languages such as C++, the Java developer has no explict control over memory management.
• Does not manage the stack.  Local primitive types and local object references are not managed by the GC.

So if the Java developer has no control over memory management, why even worry about the GC?  It turns out that memory management is an integral part of an application's performance, all things being equal.  The more memory that is required for the application to run, the greater the likelihood that computational efficiency suffers. To that end, the developer has to take into account the amount of memory being allocated when writing code.  This translates into the amount of heap memory being consumed.

Memory is split into two types:  stack and heap.  Stack memory is memory set aside for a thread of execution e.g. a function.  When a function is called, a block of memory is reserved for those variables local to the function, provided that they are either a type of Java primitive or an object reference.  Upon runtime completion of the function call, the reserved memory block is now available for the next thread of execution.  Heap memory, on the otherhand, is dynamically allocated.  That is, there is no set pattern for allocating or deallocating this memory.  Therefore, keeping track or managing this type of memory is a complicated process. In Java, such memory is allocated when instantiating an object:

String s = new String();  // new operator being employed
String m = "A String";    /* object instantiated by the JVM and then being set to a value.  The JVM
calls the new operator */

Learning SQL development can seem like an overwhelming task at first. However, mastering just a few key points will help ease your way through 80 percent of the day-to-day challenges when writing stored procedures and solving common problems. Here are three important SQL development factors to keep in mind:

Outer Joins
One of the most crucial things to understand in SQL server are joins. Joins are a way to retrieve data from two or more tables based on logical relationships between them. Joins dictate how Microsoft SQL Server ought to use data from one table to select the rows in another table.

In my experience inner joins are intuitive while outer joins can present additional hours of grief by overlooking associations in the other table(s). The outer join is the key to answering questions about what the database does not have. For example, if you need to make a query to display all the students who are without report-cards, you’ll need a left join to get all students coupled with a “where clause” to return the ones who have nulls for their report card table columns in the results.

Many talented Java script programmers have muddled through the SQL Server by deficient coding around the inner join. As a result, their queries can take five hours to run, whereas, properly written left joins, can take only two seconds to run.

Aggregation
Grouping results comes up in SQL a lot more than you might think. Knowing how to write a query when answering questions such as, “What’s the average grade for each teacher’s student list?” is invaluable. This kind of question cannot be answered with a single table or solely by joins.  You’ll often find you need to use joins in conjunction with group by statements. Always write the raw query first and then look at the results. Next, you have to figure out the best way to group them, rewrite your select clause and add a group by clause in the end.

Digging Through Data
I find this is the most lacking skill in many programmers. In fact, many otherwise-talented programmers holding Master’s Degrees fail to get jobs because they couldn’t analyze rows of data objectively during interviews. It’s just something that’s not taught but is crucial to get under you belt. Why? Eventually, some query is not going to perform as you may expect. And, the only way to find discrepancies is to look at rows of data, identify what join isn’t finding a match or where bad data is throwing things into chaos. Get familiar with how joins actually work, even if you have to manually walk through the logic of a large stored procedure’s tree of joins. It’s boring and time-consuming but absolutely necessary.

Take the time to master the core skills that will make you a successful SQL Programmer and avoid queries that run for five hours!

There are a lot of articles you will find on the internet that talk about the tenants of having a successful professional career. From soft-skills to job relevant skills, there is an unending list of the do’s and don’ts for establishing a great career. However, a successful career in information technology commands some specific efforts and focus. As a result, it is critical to focus on these 4 key tenants that can help you establish a promising and successful career in Information Technology.

·         Be Multi-lingual– This is the analogy of Steve Job’s famous quote ‘Stay Hungry, Stay Foolish’ as it applies to Information Technology. Gone are the days when you could train yourself on a specific programming language say Java or C++ and code your way to a successful career. The best programmers of today and tomorrow are pushing the limits and becoming experts in one of more languages. Knowing more than one programming language instantly makes you more employable since you can add value to multiple projects that require different languages. If you need proof, IT professionals knowing more than one language can attract a salary premium of £10,000 . Additionally, there is no telling how dynamic technology is and by being open to constantly learning new languages you will position yourself to get technology jobs that did not exist a few years ago

·         Go Beyond the ‘How’, Focus On ‘Why’: A common theme with most information technology professionals is their ability to figure out the HOW or, in other words, applying their technical know-how in achieving the solution to a problem. This is especially true when you are working for a service based IT organization where your key job is to develop a solution for the client’s business problem. Yes, you are and will get paid to be good at the ‘How’ but to advance a career in IT; it will help you immensely to also start focussing on the ‘Why’. This stems from a famous quote by Einsten “If I were given one hour to save the planet, I would spend 59 minutes defining the problem and one minute resolving it”. In essence, spend time in understanding ‘Why’ are your trying to solve the problem before you get down with figuring out the ‘How’ part. The reasons for developing this mindset are two-fold. One, you will instantly distinguish yourself from thousands of other IT peers who are content with the ‘How’ part. Two, there is a good chance that you want to get ahead in your career not only as a programmer but as a system architect or a business solution consultant. This is where the habit of asking the right questions pertaining to why a certain IT solution is requires will help you build the right solution.

·         Focus on the impact and results (Financial impact):This may not apply to IT professionals who are early in their careers but is paramount for senior IT professionals. For the most part, IT departments are required to make sure that the systems and the solutions function as desired and help the business run efficiently. In other words, the key metric for success for most IT professionals is being extremely good at technology, languages and Quality Assurance. However, the times are changing! No longer is the Chief Information Officer (CIO) in charge of making IT decisions. With organizations closely guarding the ROI of their investment in technology, CIOs are increasingly required to be cognizant of the financial benefits of technology so that they can justify the spending on IT. No wonder than that CFOs are increasingly pressurizing CIOs to get their act together

Many of us who have iPhones download every interesting app we find on the App Store, especially when they’re free. They can range from a simple payment method app, to a game, to a measurement tool. But, as you may have noticed, our phones become cluttered with tons of pages that we have to swipe through to get to an app that we need on demand. However, with an update by Apple that came out not so long ago, you are able to group your applications into categories that are easily accessible, for all of you organization lovers.

To achieve this grouping method, take a hold of one of the applications you want to categorize. Take a game for example. What you want to do is press your finger on that particular application, and hold it there until all of the applications on the screen begin to jiggle. This is where the magic happens. Drag it over to another game application you want to have in the same category, and release. Your applications should now be held in a little container on your screen. However, a step ago, if you did not have another game application on the same screen, and since you can’t swipe, try putting the held game application on any application you choose, and simply remove that extra application from the list, after moving over another gaming application from a different page.