我是Micronaut框架的新手,我正在尝试使用entitymanager创建我的存储库。 我创建了这样的存储库
public interface EmployeeRepository {
Employee save(@NotNull Employee employee);
Employee update(@NotNull Employee employee);
List<Employee> findAll();
Optional<Employee> findById(@NotNull Long id);
}
并且我使用此类来实现接口并注入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:
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:我已启用注释处理
答案 0 :(得分:1)
对于您的项目,您还没有提供足够的信息来确定缺少的内容,但是我在https://github.com/jeffbrown/mohamedmiledijpa为您创建了一个有效的示例。
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);
}
}
compile "io.micronaut.configuration:micronaut-hibernate-jpa"
一切似乎都有效:
~ $ 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"}]
答案 1 :(得分:0)
我遇到了这个问题,我找到了解决方案:
如果您使用@PersistenceContext 来注入 EntityManger,则需要包含此依赖项:
{使用 Gradle}
compile "io.micronaut.configuration:micronaut-jdbc-hikari"
或 {使用 Maven}
<dependency>
<groupId>io.micronaut.sql</groupId>
<artifactId>micronaut-jdbc-hikari</artifactId>
<scope>compile</scope>
</dependency>
因为这是 micronaut 定位 application.yml 中定义的数据源的方式。