Retrieving an entity without a default constructor

Edward.java

package net.millenary.gtdev.exmaples.domain.edward;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;

@Entity
public class Edward {

	@Id
	@GeneratedValue(strategy = GenerationType.AUTO)
	private Long id;

	private final Integer age;

	public Edward(Integer age) {
		this.age = age;
	}

	public Integer getAge() {
		return age;
	}

}

EdwardRepository.java

package net.millenary.gtdev.exmaples.domain.edward;

import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;

@Repository
public interface EdwardRepository extends JpaRepository<Edward, Long> {}

EdwardTester.java

package net.millenary.gtdev.exmaples.domain.edward;

import javax.annotation.PostConstruct;
import javax.persistence.EntityNotFoundException;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class EdwardTester {

	private final EdwardRepository repository;

	@Autowired
	public EdwardTester(EdwardRepository repository) {
		this.repository = repository;
	}

	@PostConstruct
	private void showAgeOfEdward() {
		/* 20歳のエドワードを永続化 */
		Edward edward = new Edward(20);
		this.repository.saveAndFlush(edward);

		/* ID 1 のエドワードを取得 */
		edward = this.repository.findById(1L).orElseThrow(() -> new EntityNotFoundException("Edward has gone"));
		System.out.println(edward.getAge());
	}

}