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 */

Microsoft has now come up with a surface tablet to compete with the Apple iPad. The Surface is the known as the ‘iPad killer’ and ‘Microsoft iPad’. Microsoft has stuck to production of software till date but this is one of its latest hardware devices that is expected to take over the Apple iPad. This is a new challenge posed by Microsoft to Apple.

            The Microsoft Surface saw its official release on 19^th June in the city of Los Angeles. It has made a great first impression and seems to be beginning a new start in the competition between the best tablets in the international market. It has 10.6’’ screen and a magnetic cover that can be used as a keyboard and also as a kickstand in order to place the device upright on tables. There has been a paradigm shift in Microsoft’s policy when it decided to do away with the tile-based Metro theme for its Desktop that is almost a trademark with it.

            There are many features that make the Surface more like a laptop than like a tablet- the most prominent one being the built- in keyboard that will be useful for business customers. As Microsoft Surface employs Windows 8 as an operating system, which is also used in its computers and laptops, it will be a lot easier for customers to switch among their devices.

            The tablet was announced by Microsoft’s CEO, Steve Ballmer, in Los Angeles at a special press conference. It was hailed to be the first of an entirely new family of a number of devices being created and developed by the company. The Surface has a thickness of 9.3mm and weighs 1.5 pounds. It has a kickstand and keyboard for its cover. It is 0.1 mm thinner than the iPad 3, which is the latest iPad from Apple.

In this tutorial I am going to give you a gentle introduction to network programming in Python. If you are new to programming or new to Python then that may seem like a daunting thought. But read on and you will be pleasantly surprised how easy it is.

Like most modern programming languages, Python was designed for networking from the very beginning, and thanks to that, a lot of the networking tasks you would want to accomplish with the language are made a whole lot easier.

Network communication is a large topic, but if it is something that interests you then read on because in this tutorial I will show you how to download a web page. I will show you how easy Python makes tasks like this.

Take a look at the following code:

import urllib
	
con = urllib.urlopen("http://hartmannsoftware.com")
page = con.read()
con.close()
print page