Redis

https://github.com/spring-boot-tutorials/spring-data-redis

In this article we will configure Spring Boot to connect to a Redis database.

Redis Server

Install and run Redis server

brew install redis
brew services start redis

Create Initial Code Base

Go to https://start.spring.io/
Click Add Dependencies, search for redis, then add
Click Add Dependencies, search for Lombok, then add
Click Generate

Dependencies

Dependencies used in pom.xml

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>
<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <optional>true</optional>
</dependency>

Properties

In src/main/resources/application.properties let’s add the following properties so the Spring Boot application can connect to the database

spring.data.redis.host=localhost
spring.data.redis.port=6379

# Optional: Redis database index
#spring.data.redis.database=0
# Optional: if Redis requires authentication
#spring.data.redis.password=your_password
# Optional: connection timeout in milliseconds
#spring.data.redis.timeout=60000

Model

Let’s create a new POJO src/main/java/com/example/Student.java

@Data
@SuperBuilder
@NoArgsConstructor
@RedisHash("Student")
public class Student implements Serializable {

    public enum Gender {
        MALE, FEMALE
    }

    private String id;
    private String name;
    private Gender gender;
    private int grade;
}

Repository

Next we will create a Spring repository to CRUD against the database.

This file will be called src/main/java/com/example/StudentRepository.java

@Repository
public interface StudentRepository extends CrudRepository<Student, String> {

}

Main

Now let’s use this repository.

Go back to MainApplication.java and add the following:

@SpringBootApplication
public class RedisExampleApplication implements CommandLineRunner {

    public static void main(String[] args) {
            SpringApplication.run(RedisExampleApplication.class, args);
    }

    @Autowired
    StudentRepository studentRepository;

    @Override
    public void run(String... args) throws Exception {
            studentRepository.deleteAll();

            // 1. save
            Student student = Student.builder()
                            .name("John Doe")
                            .gender(Student.Gender.MALE)
                            .grade(50)
                            .build();
            student = studentRepository.save(student);
            System.out.println(student);

            // 2. findAll
            Iterable<Student> students = studentRepository.findAll();
            students.forEach(System.out::println);

            student = studentRepository.findById(student.getId()).get();
            System.out.println(student);

            // 3. Updating
            student.setName("Richard Watson");
            student = studentRepository.save(student);
            System.out.println(student);

            // 4. Deleting
            studentRepository.deleteById(student.getId());
    }
}

Run Application

Open terminal at project root and execute the following:

mvn spring-boot:run

There should be no errors and the output will display all the CRUD operations.