Java vs C++: Which Language is Right for Your Software Project?
In one corner, you have C++ —a C language with classes developed by Bjarne Stroustrup in 1985 that's great for writing systems-level code. In the other corner you have the Java programming language—developed by Sun Microsystems with the mantra: “write once, run anywhere.”
Which language is right for your software project?
You’ve probably done a little research into the right language, but it’s difficult for someone without software development expertise to determine which one is right.
Both Java and C++ have been in production for years. They both have similar syntax, support object-oriented programming (OOP), and they both power some of the biggest enterprise platforms on the market. Most C++ programmers will tell you that converting to a Java project is easy for them since style and syntax are very similar.
Even with the similarities, however, the two languages are worlds apart. Java is an interpreted language, while C++ is a compiled language. This dissimilarity will play a huge role in your future project. In this article we’re going to take a look at the top differences between Java and C++.
What are the differences between Java and C++
A common misconception is that if a language is similar to another, then it must be similar in functionality. While Java and C++ are similar in syntax, they are far more dissimilar in the way they execute and process.
Interpreted vs. compiled
Java is an interpreted language, which means it is “translated” to binary at the time of execution. This allows it to run on any operating system regardless of where it was written. C++ is a compiled language, which means your program is compiled on a specific operating system and runs only on that particular operating system. If you want it compatible with another operating system, you must compile your program on it.
Like most high-level programming languages, Java supports garbage collection for automated memory management. In C++, you have to manage memory manually with the help of designated operators and pointers.
Java is a memory-safe language, which means if you attempt to assign values outside of the given array parameters, the programmer receives an error. C++ is much more flexible, but this comes at a price. C++ will allow the programmer to assign values outside of the allocated memory resources, but this can later cause bugs and serious crashes during run-time.
Speed and performance
Java is a favorite among developers, but because the code must first be interpreted during run-time, it’s also slower. C++ is compiled to binaries, so it runs immediately and therefore faster than Java programs.
The difference between C++ and Java in multithreading lies in the level of abstraction you have available for simplifying the writing of concurrent programs. As a low-level language, C++ only gained the support of a standard library for multithreading with the addition of C++11. Before that, it was an arduous chore of managing POSIX threads or p threads in C. Java has long provided more tools and built-in functions for writing concurrent code. C++ does have a slight performance advantage here, though, due to it being closer to the hardware.
Pointers are a C++ construct that allows you to manage values directly in memory spaces. Java does not support pointers, so you are only able to pass values using value references.
C++ has both a global scope and a namespace scope to allow data and functions to exist outside of classes. Because Java follows a single inheritance root hierarchy, it does not have a namespace scope.
Class and filename relationship
In Java, there exists a strict relationship between the public class name and file name—your program won’t compile unless they are identical. There is no such restriction in C++; your class and file names can be distinct as class declarations are handled by the header file.
Compatibility with other programming languages
As a low-level compiled language, C++ is compatible with most other high-level languages. Java, however, is not compatible with other languages.
Most object-oriented languages follow a singly rooted hierarchy where all classes must descend from other classes except for a single root class that descends from no one. Java follows this single inheritance system. Because C++ is both procedural and object oriented, it doesn’t follow a specific root hierarchy.
The syntax for declaring variables in C++ and Java is similar in that if C is a class in either language, the following operation will declare x to be type C:
However, there is a subtle difference beneath the hood, in that in C++ this creates an object that is an instance of Class C while in Java this does not create an object but rather a pointer that can point to that object.
Java was built to be platform independent by design. As long as the target machine has the Java Virtual Machine (JVM) installed, it will be able to compile Java into bytecode that can be run in a Java Runtime Environment (JRE). C++ is not generally considered portable because it lacks this standard implementation. Typically C++ source code must be compiled on every platform, making it platform dependent.
Direct call support for native system libraries
C++ is great for system-level programming because it allows the programmer to make direct calls to native system libraries. As a higher-level language, Java requires additional tools (e.g., Java Native Interface or Java Native Access) to access native features.
Structures and unions
A structure contains an ordered group of data objects and a union is an ordered group of data objects that must all start at the same location in memory. Java does not support structures and unions. C++ supports both of these constructs and treats them like classes with members and inheritance set to public by default.
Run time errors
When a C++ program suddenly stops running, you must manually find the runtime error. In Java, runtime error detection is handled by the system.
Concerning type semantics, primitive and object types are consistent for C++, but not for Java.
Operator overloading allows a single operator to have different implementations depending on the argument it receives. Method overloading expands this property to methods. Both types of overloading are supported by C++ but only method overloading is supported by Java, which restricts programmers from defining their own operator overloads.
C++ achieves dynamic polymorphism by providing the virtual keyword to indicate which functions can be overridden in a derived class. Java lacks a virtual keyword, but allows all non-static methods to be overridden by default.
Documentation & comment
C++ is very close to the C language and similarly does not support documentation and commenting. Like most high-level languages Java supports these features.
Access control and object protection
C++ gives you granularity and flexibility in how you can access and therefore protect your objects. The end result is a strong encapsulation of objects. By comparison, Java's object model has weaker encapsulation.
Because memory management is manual in C++, so, too is the management of objects. Programmers must use the "new" and "delete" operators to create and destroy objects. Similarly, constructors and destructors are used for class objects. Java relies on automatic garbage collection to handle objects, but does support the use of constructors.
Scope resolution operator
The scope resolution operator allows C++ programmers to access global variables and define methods outside a class. Java lacks support for this operator due to its single inheritance model in which all objects inherit from a single root.
The try, catch, and throw keywords are the bread and butter of exception handling in programming. The key difference here is that C++ allows all types to be thrown as exceptions. Java requires you to specify throwable objects before they can be thrown as an exception.
While both languages are general purpose, they do have their niches. Java is the foundation program for Android applications, so it’s the general choice for mobile developers. It’s also used in many standard enterprise app ecosystems such as Oracle. C++ is a low-level language used to power hardware and low-level programs such as device drivers and network analysis tools.
C++ vs. Java: Similarities
C++ and Java have a few similarities. These similarities are more relevant to a developer using the language than a client looking for a developer. You should generally look for a developer who excels in their language of choice, but the similarities between languages are useful should you find a developer you like to work with and need to edit code in a different language.
Looping structures, classes, defining variables, and conditional operators are very similar in both languages. This makes it easy for developers to work cross-platform should you have several projects that use both languages.
When your program starts, the compiler or interpreter looks for where it needs to begin execution. Both Java and C++ look for the “main” entry point.
The idea of object orientation is that the languages use classes that represent components of your program. Each class then contains methods and properties that define it. Both C++ and Java are object-oriented languages, which makes your program much more modular so you can reuse code for other programs.
Java vs C++: Which one is right for your project?
Both Java and C++ can be used to create a wide variety of programs. However, the language you use is determined by what you want developed.
C++ is generally reserved for software that needs “hardware-level” manipulation. One difference between C++ and Java is that C++ is closest to machine language, which makes it much more viable for software that needs to run quickly and requires the ability to work directly with your computer’s memory, hard drive, CPU or other devices. C++ is also common with gaming applications where speed is necessary.
You can manipulate hardware with Java, but it’s not a common language for low-level programming since it’s a “safer” language. Because Java won’t allow you to perform certain functions to protect the PC, it’s preferred for higher level applications.
Java is the foundation for Android development, so if you want a mobile application specifically for Android, then Java will be your language of choice. Java is also common for web and desktop apps as well as applications that run on servers. Java is more widely known and versatile, so it’s also easier to find a Java developer than a “harder” language such as C++.
Overall, C++ can be used for almost anything, but it’s not always necessary to use it. Java is usually sufficient and can be much more effective for your project. You can find more developers who know Java, and you’ll be able to find more developers to pick up where your former developer left off if you part ways.
The best way to make a firm decision is to post your project and ask developers for their opinions. They can tell you which language is right for your project to help guide you to the right solution.