[# 1 Java] Basics of Java-Major premise before studying-

Hello, this is Moe. This time I would like to write about Java, which inspired me to come into contact with programming languages.

What is Java in the first place?

Java is one of the programming languages that needs to be compiled and used to create programs. With Java, you can develop a variety of programs that run on different computers.
Programmers who have mastered Java are currently the most sought after in the market, so if you think about the future, you may want to start studying Java for the time being.
However, Java has some unusual characteristics compared to other programming languages.

--Java features --Easy to learn and standard basic grammar --Supports object-oriented programming to support large-scale development --A richly prepared and convenient instruction group --Versatility that works the same in any environment of Windows, Mac, Linux

Java works everywhere! Is a language created with the motto. Therefore, instead of translating it into a machine language that can be understood by a specific computer, we create an intermediate language that can be used by any computer.
When it is executed, the Java Virtual Machine (Java VM) installed on each computer translates it into machine language and executes it. It is easy to understand if you have the image that you must first translate into English and then into another language instead of translating into "Japanese → Chinese" or "Japanese → German" to execute the program. think.

Let's write Java source code

A Java file can be completed by adding the extension ".java" with a text editor, but it cannot be executed unless an execution environment is prepared. I built the environment by referring to Using AdoptOpenJDK.

Java integrated development environment

After creating a file, Java translates a program called compilation into the source code, converts it to byte code, and then executes it. By the way, the translation software that performs this translation work is called a compiler. After compiling, it also instructs software called an interpreter to execute bytecode. This interprinter has a mechanism called JavaVM inside, and converts bytecode into machine language that the CPU can understand.

Programs written by humans are executed only after being translated so that the computer can understand them in this way, but it is rare to develop such settings by themselves.
Actually, it is done using the "Integrated Development Environment (IDE)" that makes it possible to improve the efficiency of program development, such as "coding", "compilation", "testing", and "debugging" required for Java development. There are several types of this, but let's set up a development environment that suits you. By the way, I use Eclipse and IntelliJ IDEA, and I mainly use Eclipse. In selecting the development environment, I read [For beginners] Explanation of Java development tool types with images.


Program development has a convenient environment called an integrated development environment, and there is also a framework that assists in its development. This is a system in which the entire processing flow is implemented in advance, and some specific processing in it can be implemented and fitted by yourself. By utilizing this framework, developers can improve the efficiency of development.

Is the basic story of Java like this? I will post again!

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