本文介绍了如何在Micronaut中使用entitymanager？的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我是Micronaut框架的新手，我正在尝试使用entitymanager创建我的存储库。
我这样创建我的存储库
I'm new in Micronaut framework and I'm trying to use entitymanager to create my repository.I created my repository like this
public interface EmployeeRepository {
Employee save(@NotNull Employee employee);
Employee update(@NotNull Employee employee);
List<Employee> findAll();
Optional<Employee> findById(@NotNull Long id);
}
我使用此类来实现接口并注入entitymanager
and I used this class to implement the interface and to inject entitymanager
@Singleton
public class EmployeeRepositoryImpl implements EmployeeRepository{
@PersistenceContext
private EntityManager entityManager;
public EmployeeRepositoryImpl(@CurrentSession EntityManager entityManager) {
this.entityManager = entityManager;
}
@Override
@Transactional
public Employee save(@NotNull Employee employee) {
entityManager.persist(employee);
return employee;
}
@Override
@Transactional
public Employee update(@NotNull Employee employee) {
return entityManager.merge(employee);
}
@Override
@Transactional(readOnly = true)
public List<Employee> findAll() {
String qlString = "SELECT * FROM Employee";
TypedQuery<Employee> query = entityManager.createQuery(qlString, Employee.class);
return query.getResultList();
}
@Override
@Transactional(readOnly = true)
public Optional<Employee> findById(@NotNull Long id) {
return Optional.ofNullable(entityManager.find(Employee.class, id));
}
}
问题是我总是遇到此错误：
The problem is that I have always this error :
Message: No bean of type [javax.persistence.EntityManager] exists. Ensure the class is declared a bean and if you are using Java or Kotlin make sure you have enabled annotation processing.
Path Taken: new $EmployeeControllerDefinition$Intercepted([EmployeeRepositoryImpl employeeRepository],BeanContext beanContext,Interceptor[] interceptors) --> new $EmployeeRepositoryImplDefinition$Intercepted([EntityManager entityManager],BeanContext beanContext,Interceptor[] interceptors)
io.micronaut.context.exceptions.DependencyInjectionException: Failed to inject value for parameter [entityManager] of class: com.milamed.dao.$EmployeeRepositoryImplDefinition$Intercepted
PS：我启用了注释处理
PS: I have enabled the annotation processing
推荐答案
您没有为您的项目提供足够的信息来确定丢失的内容，但是我在。
You haven't provided enough about your project to know for sure what is missing but I have created a working example for you at https://github.com/jeffbrown/mohamedmiledijpa.
package mohamedmiledijpa;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
@Entity
public class Employee {
@Id
@GeneratedValue
private Long id;
private String name;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
}
package mohamedmiledijpa;
import javax.validation.constraints.NotNull;
import java.util.List;
import java.util.Optional;
public interface EmployeeRepository {
Employee save(@NotNull Employee employee);
Employee update(@NotNull Employee employee);
List<Employee> findAll();
Optional<Employee> findById(@NotNull Long id);
}
package mohamedmiledijpa;
import io.micronaut.configuration.hibernate.jpa.scope.CurrentSession;
import io.micronaut.spring.tx.annotation.Transactional;
import javax.inject.Singleton;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.TypedQuery;
import javax.validation.constraints.NotNull;
import java.util.List;
import java.util.Optional;
@Singleton
public class EmployeeRepositoryImpl implements EmployeeRepository{
@PersistenceContext
private EntityManager entityManager;
public EmployeeRepositoryImpl(@CurrentSession EntityManager entityManager) {
this.entityManager = entityManager;
}
@Override
@Transactional
public Employee save(@NotNull Employee employee) {
entityManager.persist(employee);
return employee;
}
@Override
@Transactional
public Employee update(@NotNull Employee employee) {
return entityManager.merge(employee);
}
@Override
@Transactional(readOnly = true)
public List<Employee> findAll() {
String qlString = "SELECT e FROM Employee e";
TypedQuery<Employee> query = entityManager.createQuery(qlString, Employee.class);
return query.getResultList();
}
@Override
@Transactional(readOnly = true)
public Optional<Employee> findById(@NotNull Long id) {
return Optional.ofNullable(entityManager.find(Employee.class, id));
}
}
package mohamedmiledijpa;
import io.micronaut.http.annotation.Body;
import io.micronaut.http.annotation.Controller;
import io.micronaut.http.annotation.Get;
import io.micronaut.http.annotation.Post;
import java.util.List;
@Controller("/employee")
public class EmployeeController {
private EmployeeRepository employeeRepository;
public EmployeeController(EmployeeRepository employeeRepository) {
this.employeeRepository = employeeRepository;
}
@Get("/")
public List<Employee> list() {
return employeeRepository.findAll();
}
@Post("/")
public Employee create(@Body Employee employee) {
return employeeRepository.save(employee);
}
}
> https://github.com/jeffbrown/mohamedmiledijpa/blob/f6500d3fb24d29
https://github.com/jeffbrown/mohamedmiledijpa/blob/f6500d3fb24190ed59ca64dcc28a02f8069fedfd/build.gradle#L29
compile "io.micronaut.configuration:micronaut-hibernate-jpa"
这一切似乎都起作用：
~ $ curl http://localhost:8080/employee
[]
~ $
~ $ curl -d '{"name":"Jake"}' -H "Content-Type: application/json" -X POST http://localhost:8080/employee
{"id":1,"name":"Jake"}
~ $
~ $ curl -d '{"name":"Zack"}' -H "Content-Type: application/json" -X POST http://localhost:8080/employee
{"id":2,"name":"Zack"}
~ $
~ $ curl http://localhost:8080/employee
[{"id":1,"name":"Jake"},{"id":2,"name":"Zack"}]
这篇关于如何在Micronaut中使用entitymanager？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！