How to compile and run Java code in Visual Studio Code

Question

I downloaded Visual Studio Code and installed the "Java Extension Pack" by Microsoft.

Afterwards I downloaded the jdk1.8.0_161 and created the required environment variables as described in the "Java Extension Pack" documentation.

I then created a new file with .java ending and wrote a simple "Hello World" test program.

But how can I now compile and run the code?

Read the documentation for VSCode and the Java pack? BTW,t he link you gave for the Java pack is invalid. — Jim Garrison, Mar 22 '18 at 22:38

score 0 · Accepted Answer · answered Mar 24 '18 at 09:31

As a first step, try to compile your programm from te command line. E.g. How do I run a Java program from the command line on Windows? is a good start. You can run the commands directly in VSCode's integrated terminal. Optionally, create a VS Code build task from that command to run builds with the build command.

{
    "version": "2.0.0",
    "tasks": [
        {
            "label": "Build Foo",
            "type": "shell",
            "command": "javac foo.java",
            "problemMatcher": []
        }
    ]
}

To run/debug, create a launch config in the debug viewlet, for example:

   // Use IntelliSense to learn about possible attributes.
    // Hover to view descriptions of existing attributes.
    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
    "version": "0.2.0",
    "configurations": [
        {
            "type": "java",
            "name": "Debug (Launch)-Foo",
            "request": "launch",
            "cwd": "${workspaceFolder}",
            "console": "internalConsole",
            "stopOnEntry": false,
            "mainClass": "Foo",
            "args": ""
        },
        {
            "type": "java",
            "name": "Debug (Attach)",
            "request": "attach",
            "hostName": "localhost",
            "port": 0
        }
    ]
}

What is `debug viewlet` for running the program, is it `settings.json` in `.vscode`? — Timo, Jul 08 '23 at 20:08

score 0 · Answer 2 · edited Jul 26 '22 at 05:16

Here are the overall steps:

Install the Java Extension Pack --> you did this already
Create a Java project: Ctrl + Shift + P and type "Java". Choose the option "Java: Create Java Project"
Modify the App.java class and save it: Ctrl + S

When you save it, VS Code automatically compiles the java files for you. In the bin/app directory you'll see a file called "App.class". That's the confirmation you need.

Edit: Running the project: To run the project, hit F5. VSCode will ask if you want to add a configuration. Choose "Java: Launch Program". Make sure you have App.java opened and hit F5 one more time. That's it.

I noticed that VSCode does not deal well with packages, but that is for another question.

How to compile and run Java code in Visual Studio Code

2 Answers2

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