Comparison of C# and Java language / PDF

Comparison of C# and Java language / PDF

Introduction

Many programming languages exist today: C, C++, Microsoft Visual Basic®, COBOL, C#, Java, and so on. With so many languages, how does a software engineer decide which one to use for a project? Sometimes, a language is chosen because the developers of a company like or know it, which may be reasonable. Sometimes, a language is used because it is the latest and greatest, and this becomes a marketing tool to generate more public-relations interest in a product, which may not be reasonable in and of itself. In an ideal world, a programming language should be chosen based upon its strengths for performing a certain task —the problem to solve should determine the language to use. 

This paper would quickly become a book or series of books if it attempted to compare strengths and weaknesses, platform support, and so on for many programming languages. Rather, to limit its scope, it will attempt to compare only C# and Java. Some languages, such as C++ and Pascal, will also be used for comparison, but only to help demonstrate potential motivations for the creation of the newer programming languages with their newer features. If some weakness exists and is exposed in the older language, and then shown to be nonexistent or hidden in the newer language, this may help understand the motivation for some change made by the architect of the newer language. Knowing this motivation is often important, because otherwise it is not possible to objectively critique a language. 

For example, if a so-called “feature” that existed in a previous language is removed from the newer language, then a developer may feel that the latter is not a worthy candidate to use because it doesn’t have the power of the former.  This may not be the case; the newer language may be actually doing him a favor by saving him from falling into some known trap.

Naturally, Java came before C#, and C# was not created in a vacuum.  It is quite natural that C# learned from both the strengths and weaknesses of Java, just as Java learned from Objective-C, which learned from C, etc.  So, C# should be different than Java.  If Java were perfect, then there would have been no reason to create C#.  If C# is perfect, then there is no reason to create any new programming language.  The job would then be done.  However, the future is unclear, and both C# and Java are good object-oriented programming languages in the present, so they beg to be compared.

It is important to note that not everything can be covered here.  The subject matter is simply too large.  But the goal is to give enough information so as to help managers and software developers make a somewhat-informed choice about a language to use in certain situations.  Maybe some little language quirk in C# may make someone choose Java.  Maybe some blemish in Java will influence someone to pick C#.  Either way, this document will attempt to dive deep enough into details to possibly stir-up some old fool’s gold, or to dig-up some new hidden treasure, which aids in our goal. 

(Items shaded in gray such as the paragraph below and subsequent sections have been highlighted to separate my opinion from the rest of the paper.)

While I am not covering everything about C# and Java in this paper, I will attempt to supply some in-depth analysis on most of the topics that are covered.  I don’t believe that it is generally worthwhile just to say that some functionality exists in a language and therefore try to imply that the language is powerful.  For example, I could simply say, “C# is a good language because it is object oriented.”  Naturally, that would assume that an object-oriented language is automatically good, which, from my experience, not everyone agrees with.  So, I feel in this case that I have to show why writing object-oriented code is good first, which should strengthen the above assertion.  This can get a little tedious, but I think that it is important.

Also, I generally do not like to promote anything that I have not used.  If I say below that the “language interoperability using Visual Studio .NET is outstanding because it is very easy,” then I have run at least some basic tests to really see if it is in fact “easy.”  More than likely, while not everyone will agree with its opinions, it doesn’t just “wave its hand” by just restating what others have said; rather it tries to put what others have said to the test.

What’s similar between C# and Java?

C# and Java are actually quite similar, from an application developer’s perspective.  The major similarities of these languages will be discussed here.

All Objects are References

Reference types are very similar to pointers in C++, particularly when setting an identifier to some new class instance.  But when accessing the properties or methods of this reference type, use the ‘.’ operator, which is similar to accessing data instances in C++ that are created on the stack.  All class instances are created on the heap by using the new operator, but delete is not allowed, as both languages use their own garbage collection schemes, discussed below.

It should be noted that actual pointers may be used in C#, but they can only be manipulated in an unsafe mode, which is discouraged.  This paper will not deal with writing “unsafe” C# code not only because it is discouraged, but also because I have very little experience using it; maybe even more important, because the comparisons with Java will nearly vanish as Java does not support anything like it.

Garbage Collection

How many times have you used the new keyword in C++, then forgot to call delete later on?  Naturally, memory leaks are a big problem in languages like C++.  It’s great that you can dynamically create class instances on the heap at run-time, but memory management can be a headache.

Both C# and Java have built-in garbage collection.  What does this mean?  Forgetaboutit!  At least forget about calling delete.  Because if you don’t forget, the compiler will remind you!  Or worse, Tony might make you a Soprano.  Don’t be a wise guy; neither language gives you the permission to whack any Object that’s become expendable.  But you may be asked to call new fairly often, maybe more than you’d like.  This is because all Objects are created on the heap in both languages, meaning that the following is frowned on in either language:

class BadaBing

{

       public BadaBing()

       {

       }

}

BadaBing badaBoom();  //You can’t create temporary data but you must use parens on a constructor

The compiler will send a little message to you about this because you are attempting to create temporary storage.  See, there’s this thing you gotta do:

BadaBing badaBoom = new BadaBing();

Now badaBoom is made and has at least one reference.  Later on, you might be tempted to get rid of him yourself:

delete badaBoom;  //illegal in C# and Java – the compiler will complain

Use badaBoom as long as you want, then the garbage collector will dispose of him for you when you decide to give someone else your reference.  Waste management is a beautiful thing..............

Comparison of C# and Java language / PDF