Service In Spring Boot For Beginners

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Service in spring boot is component where you usually place your business logic of your application. So service will be the class where mostly you will write Java code. Business logic can be anything for example, when user update profile, buying items, checkout, etc.

So here's an example of simple service in spring for user registration, login, update, and remove.

@Service
public class UserService{

@UserRepository
private UserRepository userRepository;

 public User registration(User newUser){
return userRepository.save(newUser);
}

 public User login(UserDto user){
return userRepository.findByUsername(user.getUsername());
}

 public User update(Long id, User newUser){
User user = userRepository.findById(id).orElse(new User);
user.setUsername(newUser.getUsername());
user.setName(newUser.getName());
userRepository.save(user);
return user;
}

 public void remove(Long id){
userRepository.deleteById(id);
}
}

To make a class as a service, you add a @Service annotation, and on the above code we are auto wiring UserRepostiry which we already discuss on the previous post, please refer to:



And if there's something you need to know about spring, pleas leave a comment.

I am an experiences web developer, have a good problem-solving and deep understanding of software development principles. With comprehensive skill set in Java, PHP, Python, C and JavaScript. Able to do database thing like MySQL and Oracle. Along with expertise in frameworks like Spring, React, and Firebase. Have a solid understanding of software development methodologies, like Agile and Scrum. I applies best practices to ensure the development process is efficient and of the highest quality output.

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