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 */

As much as we love to assume free Wi-Fi is secure, this is far from the truth. Because you are attaching to a service many others are connected to as well, without security measures, your device can be hacked, especially if the network is unencrypted. Because this encryption involves handing out a 26-character hexadecimal key to every individual wanting to use that network, most places opt for ease of access over security. And even with a secure network, your information is vulnerable to everyone else who has the password and is on the network.

This may not seem like such a big deal and many people don’t believe they have anything to hide on their personal devices, but remember what you use on those devices. Chances are your e-mail is attached as well as all other social media sites. You may have apps that track your finances or private messages to certain others that you would never want anyone else to see. Luckily, there are steps that can be taken to reduce and prevent any unwanted information grabbers from accessing your personal information.

To start, go through your computer’s settings in order to verify your operating system’s security functions are all set to offer the highest protection. Open up the Control Panel and double check that your Firewall is enabled for both private and public networks. Then, go to Network and Sharing to open Change advanced sharing settings. In here, you can turn off file and printer sharing and network discovery for public networks.

One of the most important things to watch for is HTTPS. Hypertext Transfer Protocol Secure ensures secure communication across the web. Many of the major email systems use this when you log in (as another layer of password protection) but drop the security as soon as the login is complete. To keep this going, HTTPS Everywhere is a browser extension that gives you a secure connection when browsing some of the more popular sites. It can also be programmed for other sites you like to visit that don’t use HTTPS.

Not every place on the internet provides the choice of HTTPS, and VPNs are there to fill in the security gap. Virtual Private Networks allows data to be sent and received through public access points as if it were directly connected to a secure network. Many businesses offer this for company devices, but if you are an individual looking for that kind of security, ProXPN is a free version that can be upgraded. Unfortunately, it limits your speed, but other choices include VPNBook, OpenVPN Shield Exchange, and OkayFreedom.

With these three steps implemented, secure public Wi-Fi can be achieved. No longer will you have to worry about connecting in an unsure environment with strangers, never knowing if your information is being stolen. With all of the options free of charge, it is also an affordable means of protecting yourself that only takes a little time and effort to implement and guarantee safety.

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What are a few unique pieces of career advice that nobody ever mentions?

It’s the eternal conundrum of a hiring manager – you have to hire for every single position in the company without any first-hand experience. How to do it? If you can have a trusted programmer sit in on the interview, that’s ideal, of course. But what if you’re hiring your first programmer? Or what if you’re hiring a freelancer? Or what if company policy dictates that you’re the only person allowed to do the interviewing? Well, in that case, you need some helpful advice and your innate bullshit detector. We questioned programmers and hiring managers and compiled a list of dos and don’ts. Here are some things to ask when interviewing programmers:

Past Experience

Ask the programmer about the biggest disaster of his career so far, and how he handled it. Did he come in at midnight to fix the code? Was he unaware of the problem until someone brought it up? Did someone else handle it?  According to our programmer sources, “Anyone worth their salt has caused a major meltdown. If they say they haven’t, they’re lying. Or very, very green.” Pushing a code with bugs in it isn’t necessarily bad. Not handling it well is bad.

As usual, your biggest asset is not knowing the field, it is knowing people. Asking about career disasters can be uncomfortable, but if the interviewee is experienced and honest then she won’t have a problem telling you about it, and you will get an idea of how she handles mishaps. Even if you don’t understand what the disaster was or how it was fixed, you should be able to tell how honest she’s being and how she handles being put on the spot.

Google is one of the most popular websites in the entire world that gets millions of views each day. Therefore, it should come as no surprise that it needs a strong and reliable programming language that it can rely on to run its searches and many of the apps that Google has created. Because of this, Google uses Python to ensure that every time a user uses one of their products, it will work smoothly and flawlessly. That being said, Google uses Python in a variety of different ways, outlined below.

Code.Google.Com
Since its creation, Google has always used Python as part of its core for programming language. This can still be seen today considering the strong relationship the two have with one another. Google supports and sponsors various Python events, and Python works to better itself so that Google remains on top of cutting edge material. One way that they do this is by working with code.google.com. This is the place where Google developers go to code, learn to code and test programs. And with it being built on Python, users can experience exactly what it is that they should expect once they start using the real site.

Google AdWords
Google AdWords is a great way for people to get their websites out there, through the use of advertising. Each time a person types in a certain string of keywords, or if they have history in their cookies, then they’ll come across these AdWords. The way that these AdWords are broadcasted to online web surfers is built on the foundation from Python. Python also helps clients access their AdWord accounts, so that they can tailor where they want their advertisements to go.

Beets
If you have loads of music, but some of it is uncategorized or sitting in a music player without a name or title, Beets is for you. This Google project uses Python and a music database to help arrange and organize music. The best part about Beets is that even if it doesn’t run exactly the way that you want, you can use a bit of Python knowledge to tailor it to be more specific to your desires.

Android-Scripting
Not only does Google run off Python, but Android also has its own value for the language. Whether you are someone who is just creating your own app for your phone or if you are someone who is looking to create the next app that gets downloaded multiple millions of times, you can use Python and Android-Scripting to create an app that does exactly what you want it to do.

YouTube
YouTube one just started as a video viewer on its own, but is now a billion-dollar company that is owned by Google. YouTube uses Python to let users view and upload video, share links, embed video and much more. Much like Google itself, YouTube relies heavily on Python to run seamlessly for the amount of traffic it gets daily.

Python is not your average coding language. Instead, it is a valuable and integral part of some of the biggest websites in the world, one of which is Google. And the resources listed here are just a fraction of what Google uses Python for in total.

Related:

What Are The 10 Most Famous Software Programs Written in Python?

The Future of Java and Python

Ranking Programming Languages: Which are Gaining Popularity?

Top 10 Software Skills for 2014 and Beyond

Working With Strings In Python

Working With Lists In Python

Conditional Programming In Python