Mina Michael 4, 18 18 gold badges 62 62 silver badges bronze badges. Mrinal Mrinal 7 7 silver badges 4 4 bronze badges. Akavall Akavall 2 2 gold badges 6 6 silver badges 22 22 bronze badges. I would say your original version was better, since is the comment character in shells. To compile a Java file to runnable. Oto 'tapik' Buchta Oto 'tapik' Buchta 1, 1 1 gold badge 6 6 silver badges 6 6 bronze badges.
For a first installation, default-jdk is a must and openjdk-X-jdk is not enough. Just type sudo apt-get update , followed by sudo apt-get install openjdkjdk for a quick installation for java7, then you can play games with java :- For more detailed official Java documentation, please visit this link.
It will ask you to select a project. Hit package to generate the JAR file. Once you have created a project in the IDE, you can add files to the project using the New File wizard. Now it is openjdkjdk. How to run simple Java program on Terminal? We can run the compiler without parameters to have an interactive shell.
Fabby I'd suggest that people starting to learn Java now would be best off learning the latest version, Java 7 sudo apt-get install openjdkjdk. Also, it's best to run sudo apt-get update before install ing packages from the Terminal. Featured on Meta.
Congratulations to our 29 oldest beta sites - They're now no longer beta! Unicorn Meta Zoo 7: Interview with Nicolas. Linked 0. Related Hot Network Questions. Question feed. You can either ignore the code completion box and keep typing, or you can select one of the suggested expressions. If you would prefer not to have the code completion box automatically appear, you can turn off the feature. If you want to rename the node for a source file in the Projects window, choose Refactor from IDE's main menu.
The IDE prompts you with the Rename dialog box to lead you through the options of renaming the class and the updating of code that refers to that class. Make the changes and click Refactor to apply the changes.
This sequence of clicks might seem unnecessary if you have just a single class in your project, but it is very useful when your changes affect other parts of your code in larger projects. All rights reserved. Hide TOC. The "Hello World! Add code to the generated source file A source file contains code, written in the Java programming language, that you and other programmers can understand. Compile the source file into a. Run the program The IDE invokes the Java application launcher tool java , which uses the Java virtual machine to run your application.
In the Create Main Class field, type helloworldapp. Click Finish. The project is created and opened in the IDE.
You should see the following components: The Projects window, which contains a tree view of the components of the project, including source files, libraries that your code depends on, and so on. Both the compiler javac and launcher java are case-sensitive , so you must capitalize consistently. HelloWorldApp is not the same as helloworldapp. If you have an IDE, you can try starting it up and seeing if it complains about Java not being present. If not, congratulations! You can go to the next step. Below we cover command-line testing for Windows and Linux.
To start a command-line window:. In the command window, type javac If you do not get a message saying that the command isn't recognized, great. Please proceed to the next step! Otherwise, you need to edit your "environment variables" to tell your computer where to look for javac. Environment variables are little snippets of information that the OS uses so it won't have to keep asking you questions like "Where's your login directory? BAT file? On a Unix machine, chances are that installing the JDK will make it visible without any further twiddling.
You will use the Java compiler javac to compile your Java programs and the Java interpreter java to run them. To verify that Apple's implementation of Java 2. You will use the Java compiler javac to compile your Java programs and the Java interpreter java to run them. Mac OS X includes implementation of Java 2.
But if the system still doesn't recognize javac or java , you must fiddle with environment variables. First, figure out where the newly installed Java lives. Environment variables are set in the initialization files that are run when your shell starts up. Most people nowadays tend to use the "bash" shell, in which case the relevant initialization file is in your home directory and is named.
Step 3: Programming Now, with the Java compiler and interpreter installed, we can finally start to program! How exciting! We consider three scenarios:. You maintain a program e. After writing or editing your program using your text editor, you start a command window, navigate to the directory where you store your program using the "cd" command, compile your program at command-line. You first type.
Using a general text editor is fast. Also, an IDE can invoke Java compiler and interpreter automatically without requiring you to use a command-line window. There are many Java IDEs available. Eclipse is an IDE used by many professional software developers. Most recent machines are 64 Bit machines. After downloading Eclipse, please click it to install it.
We now use Assignment 1 as an example of how to use Eclipse. Launch Eclipse. Eclipse asks for a workspace. The workspace is where you put your Java projects. We recommend that you create a directory for CS, such as cs Select the directory and press OK. Eclipse has a concept called Project to better organize files. We recommend that you create a project for each assignment, for example ps1, for PSET 1.
We will use ps1 as the project name below.