Paradoxically, both programming languages share a lot of features, and a lot of features divide them, which does not help in distinguishing between them. I’ve decided to analyze this subject and to describe the major distinctive differences in each scripting language. In this article, I’m discussing the following issues:
- The basic differences between the two programming languages;
- The main uses of each language;
- Information about the environments in which the programming you create in each language can run;
- Their usability in reference to the creation of mobile web apps.
I hope this text will dispel your doubts and help you understand the differences between each programming language.
Java is a compiled language, which means that the code written by a programmer is transformed by means of a compiler into bytecode. The compiled class (that is code) is saved to an output file “*.class”.
What is the bytecode itself? It’s a list of instructions read by the Java Virtual Machine – JVM, i.e. the environment in which Java code is started. To compile the code written in Java, you must install the JDK (Java Development Kit) version of Java. To run programming written in Java, you need the JVM.
What is JRE (Java Runtime Environment)?
It’s a set of tools necessary to run the code (program). It enables you to start the Virtual Machine. However, it does not let you compile the code written by a programmer into bytecode.
What is JDK (Java Development Kit)?
When it comes to web development, JDK (Java Development Kit) contains all the tools included in the JRE package, it also has an ample collection of development and web development tools, among others, the Java compiler and debugger. Programmers use the JDK to create software.
How to run the written code?
Java follows the rule of ”write once, run anywhere”. This means that any program written in Java should be read by and run on any computer with the JVM installed: no matter if it’s a PC, a server, or a device with the ARM processor. Obviously, the computing power and the RAM size of the device must be sufficient for it to be able to run both the JVM and the program itself.
While working on this article, I did an experiment to check whether the programming code can run in any environment. To do that, I used my personal computer with the Ubuntu system, and I tried to run a program compiled for Ubuntu on the Raspberry Pi 3. For the purposes of the experiment, I created an app in Spring Boot which can read the level of liquid in a container in a smart house. I built the app using my own laptop. Then, I uploaded the compiled target code and started it on a Raspberry Pi 3 computer. There was no need to install any plug-ins for the app. I had no trouble running the program compiled on my laptop on the JVM in the ARM architecture.
The programmers’ community
Static vs. dynamic type checking
Static typing means assigning types to variables or constants during compilation. So, the compiler assigns the integer type to a variable containing a numeric value. If the value is textual, the compiler cannot read it and will report an error during compilation. This way, static typing allows programmers to detect many errors early, in the compilation stage.
In dynamic typing, the types are assigned as the program is started. Thus, the error described above will only be detected when the program is running. This gives rise to plenty of programming language jokes about the two, such as the one below:
Concurrency refers to the processing of multiple threads or processes. Each thread must perform certain operations and receives a determined amount of memory and time in which the processor can process data for a given thread. Overall, it gives the impression that a couple of programs or operations are read and executed simultaneously with one processor..
With regard to multithreading, in Java, concurrency is supported by the threads which allow you to assign the processor time to many programs. You can use the Thread class or the Runnable interface. What’s more, you have a number of libraries offering interesting solutions to problems connected with concurrency.
Each scripting language has undergone considerable changes over the years. Looking back on it, one can say that the changes have had a positive impact on the development of both of them.
In the case of Java, the most significant changes were brought about by the version 8, published in March 2014. It provided support for functional programming (meaning lambda expressions). Many of the operations which used to take up a series of code lines can now be expressed in a much shorter, quickly read form; and many other things were simplified as well.
Moreover, tools like ReactNative present many more opportunities than Java does. For example, they allow you to create cross-platform mobile apps. This means that once code is created, it can be used simultaneously on two mobile operating systems – Android and iOS.
From a client’s perspective, this is a perfect solution. They don’t need to hire two web development teams to build to native apps for iOS and Android. They will do well with a single team creating an app for both systems at the same time. This, in turn, results in reducing the costs of the mobile app creation considerably. However, if the app is dedicated only to Android or iOS or if the speed of performance is the critical condition, I definitely recommend creating a native application.
As a Java programmer with several years of experience