![HOW TO WRITE YOUR
FIRST PROGRAM IN JAVA
InordertostartwritingprogramsinJava,setupyour
workenvironment.ManyprogrammersuseIntegrated
DevelopmentEnvironments(IDEs)suchasEclipseand
NetbeansfortheirJavaprogramming,butonecanwrite
aJavaprogramandcompileitwithoutbloatedIDEs.
Any sort of Notepad-like program will
suffice for programming in Java.Hardcore
programmers sometimes prefer to use
text editors that are within the terminal
such as vim and emacs. A very good text
editor that can be installed on both a
Windows machine and on a linux-based
machine (Mac, Ubuntu, etc.) is Sublime
Text, which is what we will be using in
this tutorial.
Make sure that you
have the Java Software
Development
KIT installed. You will
need this for compiling
your program.
We will first create a program that prints
"Hello World." In your text editor, create
a new file and save it as
"HelloWorld.java". HelloWorld is your
class name and you will need your class
name to be the same name as your file.
Declare your class and your main
method. The main method public
static void main(String[] args) is the
method that will be executed when
the programming is running.
Write the line of
code that will
print out "Hello
World."
Put it all
together
Save your file and open
up command prompt or
terminal to compile the
program
Run the
program.
Congratulations,
you have made
your first Java
program!](https://image.slidesharecdn.com/javaprogrammingmandm-9neumannjgmnhs-150209081240-conversion-gate02/85/Java-Programming-M-M-17-320.jpg)
Java Programming (M&M)
- 2. Java is a programming language created by James Gosling from Sun Microsystem (Sun) in 1991. The first publicy available version of Java (Java 1.0) was released in 1995. Sun microsystems was acquired by the Oracle Corporation in 2010. Oracle has now the steermanship for Java.
- 3. Java is a high-level language and software-only platform. It runs on more than 50 million personal computers and on billions of devices worldwide. 9 million developers have created Java applications in all major industries. Java also allows you to play online games, chat with people around the world, calculate your mortgage interest, and view images in 3D, just to name a few. It's also integral to the intranet applications and other e-business solutions that are the foundation of corporate computing.
- 4. Trying to design a very basic chat room in JAVA RMI. My design brief is that all clients messages should be displayed to other clients and also captured and displayed on the server. I have been able to get as far as getting all client messages to display on the server side, but I am having difficulty in being able to display the messages sent by clients to other clients. I have constructed a GUI for clients in netbeans for them to type and receive text. Does anyone know of any ways I can go about solving this issue?
- 5. The Java programming language is a high-level language that can be characterized by all of the following buzzwords: • Architecture neutral •Portable •High performance •Robust •Secure •Object oriented •Distributed •Simple •Multithreaded •Dynamic In the Java programming language, all source code is first written in plain text files ending with the .java extension. Those source files are then compiled into .class files by the javac compiler. A .class file does not contain code that is native to your processor; it instead contains bytecodes — the machine language of the Java Virtual Machine (Java VM). The java launcher tool then runs your application with an instance of the Java Virtual Machine.
- 7. OR
- 9. The two main components of the Java platform are the Java Application Programming Interface (API), which is a library of Java command lines and the Java Virtual Machine (JVM) that interprets Java
- 10. A platform is the hardware or software environment in which a program runs. We've already mentioned some of the most popular platforms like Microsoft Windows, Linux, Solaris OS, and Mac OS. Most platforms can be described as a combination of the operating system and underlying hardware. The Java platform differs from most other platforms in that it's a software-only platform that runs on top of other hardware-based platforms.
- 11. You've already been introduced to the Java Virtual Machine; it's the base for the Java platform and is ported onto various hardware- based platforms. The API is a large collection of ready-made software components that provide many useful capabilities. It is grouped into libraries of related classes and interfaces; these libraries are known as packages. As a platform-independent environment, the Java platform can be a bit slower than native code. However, advances in compiler and virtual machine technologies are bringing performance close to that of native code without threatening portability.
- 12. 10 REASONS WHY JAVA ROCKS MORE THAN EVER Part 1: The Java Compilerr The compiler is one of the things we take for granted in any language, without thinking about its great features. In Java, unlike C++, you can simply compile your code without thinking too much about linking, optimisation and all sorts of other usual compiler features. This is partially due to the JIT (Just In Time compiler), which does further compilation work at runtime. Part 2: The Core API The JDK’s core API consists of a very solid, stable and well-understood set of libraries. While many people complain about the lack of functionality in this area (resorting to Google Guava or Apache Commonss, people often forget that the core API is still the one that is underneath all those extensions. Again, from a C++ perspective, this is a truly luxurious situation.
- 13. Part 3: Open Source In this section, ZeroTurnaround’s Geert Bevin‘s mind-set aligns well with our own at Data Geekery when it comes to the spirit of Open Source – no matter whether this is about free-as-in-freedom, or free-as- in-beer, the point is that so many things about Java are “open”. We’re all in this together. Part 4: The Java Memory Model Again, a very interesting point of view from someone with a solid C++ background. We’re taking many things for granted as Java has had a very good threading and memory model from the beginning, which was corrected only once in the JDK 1.5 in 2004, and which has built a solid grounds for newer API like actor-based ones, Fork/JOIN, etc.
- 14. Part 5: High-Performance JVM The JVM is the most obvious thing to talk about it has allowed for so many languages to work on so many hardware environments, and it runs so fast, nowadays! Part 6: Bytecode Bytecode is a vendor-independent abstraction of machine code, which is very predi ctable and can be generated, manipulated, and transformed by various technologies. We’ve recently had a guest post by Dr. Ming-Yee Iu who has shown how bytecode transformations can be used to emulate LINQ in Java. Let’s hear it
- 15. Part 7: Intelligent IDEs 15 years ago, developing software worked quite differently. People can write assembler or C programs with vi or Notepad. But when you’re writing a very complex enterprise-scale Java program, you wouldn’t want to miss IDEs, nowadays. We’ve blogged about various reasons why SQLJ has died. The lack of proper IDE support was one of them. Part 8: Profiling Tools Remember when Oracle released Java Mission Control for free developer use with the JDK 7u40? Profiling is something very very awesome. With modern profilers, you can know exactly where your bottleneck is by simply measuring every aspect of your JVM. You don’t have to guess, you can know.
- 16. Part 9: Backwards Compatibility While backwards-compatibility has its drawbacks, too, it is still very impressive how long the Java language, the JVM, and the JDK have existed so far without introducing any major backwards-compatibility regressions. The only thing that comes to mind is the introduction of keywords like assert and enum. Part 10: Maturity With Innovation In fact, this article is a summary of all the others, saying that Java has been a very well-designed and mature platform from the beginning without ever ceasing to innovate. And it’s true. With Java 8, a great next step has been published that will – again – change the way the enterprise perceives software development for good.
- 17. HOW TO WRITE YOUR FIRST PROGRAM IN JAVA InordertostartwritingprogramsinJava,setupyour workenvironment.ManyprogrammersuseIntegrated DevelopmentEnvironments(IDEs)suchasEclipseand NetbeansfortheirJavaprogramming,butonecanwrite aJavaprogramandcompileitwithoutbloatedIDEs. Any sort of Notepad-like program will suffice for programming in Java.Hardcore programmers sometimes prefer to use text editors that are within the terminal such as vim and emacs. A very good text editor that can be installed on both a Windows machine and on a linux-based machine (Mac, Ubuntu, etc.) is Sublime Text, which is what we will be using in this tutorial. Make sure that you have the Java Software Development KIT installed. You will need this for compiling your program. We will first create a program that prints "Hello World." In your text editor, create a new file and save it as "HelloWorld.java". HelloWorld is your class name and you will need your class name to be the same name as your file. Declare your class and your main method. The main method public static void main(String[] args) is the method that will be executed when the programming is running. Write the line of code that will print out "Hello World." Put it all together Save your file and open up command prompt or terminal to compile the program Run the program. Congratulations, you have made your first Java program!
- 18. MATTHEW CALIFF CALIP MARIFER ABAO 9 S S C N E U M A N N J A V A P R O G R A M M I N G