Create your first Azure function with Java and IntelliJ

This article shows you:

  • How to create a serverless function project with IntelliJ IDEA
  • Steps for testing and debugging the function in the integrated development environment (IDE) on your own computer
  • Instructions for deploying the function project to Azure Functions

If you don't have an Azure subscription, create a free account before you begin.

Set up your development environment

To develop a function with Java and IntelliJ, install the following software:

Installation and Sign-in

  1. In IntelliJ IDEA's Settings/Preferences dialog (Ctrl+Alt+S), select Plugins. Then, find the Azure Toolkit for IntelliJ in the Marketplace and click Install. After installed, click Restart to activate the plugin.

    Azure Toolkit for IntelliJ plugin in Marketplace

  2. To sign in to your Azure account, open sidebar Azure Explorer, and then click the Azure Sign In icon in the bar on top (or from IDEA menu Tools/Azure/Azure Sign in). The IntelliJ Azure Sign In command

  3. In the Azure Sign In window, select Device Login, and then click Sign in (other sign in options).

    The Azure Sign In window with device login selected

  4. Click Copy&Open in Azure Device Login dialog .

    The Azure Login Dialog window

  5. In the browser, paste your device code (which has been copied when you click Copy&Open in last step) and then click Next.

    The device login browser

  6. In the Select Subscriptions dialog box, select the subscriptions that you want to use, and then click OK.

    The Select Subscriptions dialog box

Create your local project

In this section, you use Azure Toolkit for IntelliJ to create a local Azure Functions project. Later in this article, you'll publish your function code to Azure.

  1. Open IntelliJ Welcome dialog, select Create New Project to open a new Project wizard, select Azure Functions.

    Create functions project

  2. Select Http Trigger, then click Next and follow the wizard to go through all the configurations in the following pages; confirm your project location then click Finish; Intellj IDEA will then open your new project.

    Create functions project finish

Run the Function App locally

  1. Navigate to src/main/java/org/example/functions/HttpTriggerFunction.java to see the code generated. Beside the line 17, you will notice that there is a green Run button, click it and select Run 'azure-function-exam...', you will see that your function app is running locally with a few logs.

    Local run functions project

    Local run functions output

  2. You can try the function by accessing the printed endpoint from browser, like http://localhost:7071/api/HttpTrigger-Java?name=Azure.

    Local run functions test result

  3. The log is also printed out in your IDEA, now, stop the function by clicking the stop button.

    Local run functions test log

Debug the Function App locally

  1. Now let's try to debug your Function App locally, click the Debug button in the toolbar (if you don't see it, click View -> Appearance -> Toolbar to enable Toolbar).

    Local debug functions button

  2. Click on line 20 of the file src/main/java/org/example/functions/HttpTriggerFunction.java to add a breakpoint, access the endpoint http://localhost:7071/api/HttpTrigger-Java?name=Azure again , you will find the breakpoint is hit, you can try more debug features like step, watch, evaluation. Stop the debug session by click the stop button.

    Local debug functions break

Deploy your Function App to Azure

  1. Right click your project in IntelliJ Project explorer, select Azure -> Deploy to Azure Functions

    Deploy functions to Azure

  2. If you don't have any Function App yet, click No available function, click to create a new one.

    Deploy functions to Azure create app

  3. Type in the Function app name and choose proper subscription/platform/resource group/App Service plan, you can also create resource group/App Service plan here. Then, keep app settings unchanged, click OK and wait some minutes for the new function to be created. After Creating New Function App... progress bar disappears.

    Deploy functions to Azure create app wizard

  4. Select the function app you want to deploy to, (the new function app you just created will be automatically selected). Click Run to deploy your functions.

    Deploy functions to Azure run

    Deploy functions to Azure log

Manage Azure Functions from IDEA

  1. You can manage your functions with Azure Explorer in your IDEA, click on Function App, you will see all your functions here.

    View functions in explorer

  2. Click to select on one of your functions, and right click, select Show Properties to open the detail page.

    Show functions properties

  3. Right click on your Function HttpTrigger-Java, and select Trigger Function, you will see that the browser is opened with the trigger URL.

    Deploy functions to Azure run

Add more Functions to the project

  1. Right click on the package org.example.functions and select New -> Azure Function Class.

    Add functions to the project entry

  2. Fill in the class name HttpTest and select HttpTrigger in the create function class wizard, click OK to create, in this way, you can create new functions as you want.

    Add functions to the project select trigger

    Add functions to the project output

Cleaning Up Functions

  1. Deleting Azure Functions in Azure Explorer

    Add functions to the project select trigger

Next steps

You've created a Java functions project with an HTTP triggered function, run it on your local machine, and deployed it to Azure. Now, extend your function by...