Spring @Autowired tutorial

last modified October 18, 2023

Spring @Autowired tutorial shows how to inject dependencies in a Spring application with @Autowired annotation.

Spring is a popular Java application framework for creating enterprise applications.

Spring @Autowired

@Autowired annotation marks a constructor, field, setter method or config method to be autowired by Spring's dependency injection facilities. It is an alternative to the JSR-330 @Inject annotation.

Spring @Autowired example

The application injects a dependency with @Autowired. The dependency is a service object that returns words.

│   ├───java
│   │   └───com
│   │       └───zetcode
│   │           │   Application.java
│   │           └───service
│   │                   WordService.java
│   └───resources
│           logback.xml

This is the project structure.

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"










In the pom.xml file, we have basic Spring dependencies spring-core, spring-context, and logging logback-classic dependency.

The exec-maven-plugin is used for executing Spring application from the Maven on the command line.

<?xml version="1.0" encoding="UTF-8"?>
    <logger name="org.springframework" level="ERROR"/>
    <logger name="com.zetcode" level="INFO"/>

    <appender name="consoleAppender" class="ch.qos.logback.core.ConsoleAppender">
            <Pattern>%d{HH:mm:ss.SSS} %blue(%-5level) %magenta(%logger{36}) - %msg %n

        <level value="INFO" />
        <appender-ref ref="consoleAppender" />

The logback.xml is a configuration file for the Logback logging library.

package com.zetcode.service;

import org.springframework.stereotype.Service;
import java.util.List;
import java.util.Random;

public class WordService {

    private final List<String> words = List.of("pen", "sky",
            "rock", "forest", "falcon", "eagle");

    public List<String> all() {

        return words;

    public String randomWord() {

        return words.get(new Random().nextInt(words.size()));

WordService class is annotated with the @Service annotation. It is registered by Spring as a managed bean with the help of component scanning. This service object is later injected into the Application with @Autowired.

package com.zetcode;

import com.zetcode.service.WordService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.stereotype.Component;

public class Application {

    private static final Logger logger = LoggerFactory.getLogger(Application.class);

    private WordService wordService;

    public static void main(String[] args) {

        var ctx = new AnnotationConfigApplicationContext(Application.class);

        var bean = ctx.getBean(Application.class);


    public void run() {

        logger.info("{}", wordService.randomWord());
        logger.info("{}", wordService.randomWord());

        var words = wordService.all();
        words.stream().forEach(word -> logger.info("{}", word));

The application is annotated with outputs words using the WordService. The service dependency is injected into the Application with @Autowired.

private WordService wordService;

This is called field injection.

Note: While field injection is short and sweet, in general, it is recommended to use constructor or setter injection.

$ mvn -q exec:java
17:15:34.504 INFO  com.zetcode.Application - falcon
17:15:34.507 INFO  com.zetcode.Application - eagle
17:15:34.508 INFO  com.zetcode.Application - pen
17:15:34.508 INFO  com.zetcode.Application - sky
17:15:34.509 INFO  com.zetcode.Application - rock
17:15:34.509 INFO  com.zetcode.Application - forest
17:15:34.510 INFO  com.zetcode.Application - falcon
17:15:34.510 INFO  com.zetcode.Application - eagle

We run the application.

In this article we have injected dependencies in Spring with @Autowired.


My name is Jan Bodnar and I am a passionate programmer with many years of programming experience. I have been writing programming articles since 2007. So far, I have written over 1400 articles and 8 e-books. I have over eight years of experience in teaching programming.

List all Spring tutorials.