Java Language Guide¶
This guide introduces Azure Functions for Java using the annotation-based programming model.
Java functions are declared with @FunctionName and trigger/binding annotations such as @HttpTrigger, providing explicit metadata in familiar Java class structure.
Under Development
The Java tutorial track and recipes are under active development. This page provides a programming model overview, quick start, and cross-language comparison. For production architecture decisions, pair this page with Platform and Operations.
Main Content¶
flowchart LR
A[01 Local Run] --> B[02 First Deploy]
B --> C[03 Configuration]
C --> D[04 Logging & Monitoring]
D --> E[05 Infrastructure as Code]
E --> F["06 CI/CD"]
F --> G[07 Extending Triggers] The Java guide will follow the same 7-step tutorial structure used by the Python guide, covering all four hosting plans.
Java Model at a Glance¶
| Topic | Java on Azure Functions |
|---|---|
| Registration style | Annotation-based function method declarations |
| Core annotations | @FunctionName, @HttpTrigger, output/input binding annotations |
| Worker model | Out-of-process Java worker managed by the Functions host |
| Supported runtimes | Java 8, 11, 17, 21 |
- Function entry methods are grouped in Java classes.
- Trigger and binding behavior is declared via annotations.
- Execution context and logging are provided to handler methods.
- Dependency management follows Maven/Gradle Java ecosystem conventions.
Java vs Python Mental Model¶
| Concern | Python v2 | Java |
|---|---|---|
| Function declaration | Decorators on Python functions | Java annotations on methods |
| App container | func.FunctionApp() object | Class-based methods with annotation metadata |
| Dependency management | requirements.txt | pom.xml or build.gradle |
| Common HTTP pattern | @app.route(...) | @FunctionName + @HttpTrigger |
Quick Start: HTTP Trigger (Java)¶
package com.example;
import com.microsoft.azure.functions.*;
import com.microsoft.azure.functions.annotation.*;
import java.util.Optional;
public class HelloFunction {
@FunctionName("HelloHttp")
public HttpResponseMessage run(
@HttpTrigger(
name = "req",
methods = {HttpMethod.GET},
authLevel = AuthorizationLevel.FUNCTION,
route = "hello/{name?}")
HttpRequestMessage<Optional<String>> request,
@BindingName("name") String name,
final ExecutionContext context) {
String resolvedName = (name != null && !name.isBlank()) ? name : "world";
context.getLogger().info("Processed Java request for " + resolvedName);
return request
.createResponseBuilder(HttpStatus.OK)
.body("Hello, " + resolvedName + "! (Azure Functions Java)")
.build();
}
}
What this example demonstrates¶
- Function naming with
@FunctionName. - HTTP trigger declaration with
@HttpTrigger. - Route parameter extraction with
@BindingName. - Logging through
ExecutionContext.
Tutorial Roadmap¶
The following content is planned for the Java track:
- Tutorial track: Local run, deployment, configuration, monitoring, IaC, CI/CD across all four hosting plans.
- Recipes: Storage, Cosmos DB, Event Grid, Key Vault, Managed Identity.
- Reference docs: Runtime/version matrix notes, host settings mapping, troubleshooting patterns.
- Reference app: Planned
apps/java/implementation that mirrors the Python reference app patterns.
See Also¶
- Language Guides Overview
- Python Guide (reference implementation)
- Node.js Guide
- .NET Guide
- Platform: Architecture
- Platform: Hosting
- Operations: Deployment
- Operations: Monitoring