Spring Boot Jpa 简明教程
Spring Boot JPA - Named Queries
有时会出现需要自定义查询来完成某个测试用例的情况。我们可以使用 @NamedQuery 注解指定实体类中的命名查询，然后再在存储库中声明该方法。以下是示例。
Some time case arises, where we need a custom query to fulfil one test case. We can use @NamedQuery annotation to specify a named query within an entity class and then declare that method in repository. Following is an example.
我们在 JPA Custom Methods 章节中存储库中添加了自定义方法。现在，我们使用 @NamedQuery 添加另一个方法，并对其进行测试。
We’ve added custom methods in Repository in JPA Custom Methods chapter. Now let’s add another method using @NamedQuery and test it.
Entity - Entity.java
以下为Employee的默认代码。它表示一个带id，name，age和email列的Employee表。
Following is the default code of Employee. It represents a Employee table with id, name, age and email columns.
package com.tutorialspoint.entity;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.NamedQuery;
import javax.persistence.Table;
@Entity
@Table
@NamedQuery(name = "Employee.findByEmail",
query = "select e from Employee e where e.email = ?1")
public class Employee {
@Id
@Column
private int id;
@Column
private String name;
@Column
private int age;
@Column
private String email;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
}Repository - EmployeeRepository.java
添加一个通过名字和年龄找到员工的方法。
Add a method to find an employee by its name and age.
package com.tutorialspoint.repository;
import org.springframework.data.repository.CrudRepository;
import org.springframework.stereotype.Repository;
import com.tutorialspoint.entity.Employee;
@Repository
public interface EmployeeRepository extends CrudRepository<Employee, Integer> {
public List<Employee> findByName(String name);
public List<Employee> findByAge(int age);
public Employee findByEmail(String email);
}现在，Spring JPA 将使用命名查询中提供的查询，自动创建以上方法的实现。让我们在 test 文件中添加测试用例，从而测试所添加的方法。以下文件中的最后两个方法测试了所添加的命名查询方法。
Now Spring JPA will create the implementation of above methods automatically using the query provided in named query. Let’s test the methods added by adding their test cases in test file. Last two methods of below file tests the named query method added.
以下是 EmployeeRepositoryTest 的完整代码。
Following is the complete code of EmployeeRepositoryTest.
package com.tutorialspoint.repository;
import static org.junit.jupiter.api.Assertions.assertEquals;
import java.util.ArrayList;
import java.util.List;
import javax.transaction.Transactional;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.extension.ExtendWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit.jupiter.SpringExtension;
import com.tutorialspoint.entity.Employee;
import com.tutorialspoint.sprintbooth2.SprintBootH2Application;
@ExtendWith(SpringExtension.class)
@Transactional
@SpringBootTest(classes = SprintBootH2Application.class)
public class EmployeeRepositoryTest {
@Autowired
private EmployeeRepository employeeRepository;
@Test
public void testFindById() {
Employee employee = getEmployee();
employeeRepository.save(employee);
Employee result = employeeRepository.findById(employee.getId()).get();
assertEquals(employee.getId(), result.getId());
}
@Test
public void testFindAll() {
Employee employee = getEmployee();
employeeRepository.save(employee);
List<Employee> result = new ArrayList<>();
employeeRepository.findAll().forEach(e -> result.add(e));
assertEquals(result.size(), 1);
}
@Test
public void testSave() {
Employee employee = getEmployee();
employeeRepository.save(employee);
Employee found = employeeRepository.findById(employee.getId()).get();
assertEquals(employee.getId(), found.getId());
}
@Test
public void testDeleteById() {
Employee employee = getEmployee();
employeeRepository.save(employee);
employeeRepository.deleteById(employee.getId());
List<Employee> result = new ArrayList<>();
employeeRepository.findAll().forEach(e -> result.add(e));
assertEquals(result.size(), 0);
}
private Employee getEmployee() {
Employee employee = new Employee();
employee.setId(1);
employee.setName("Mahesh");
employee.setAge(30);
employee.setEmail("mahesh@test.com");
return employee;
}
@Test
public void testFindByName() {
Employee employee = getEmployee();
employeeRepository.save(employee);
List<Employee> result = new ArrayList<>();
employeeRepository.findByName(employee.getName()).forEach(e -> result.add(e));
assertEquals(result.size(), 1);
}
@Test
public void testFindByAge() {
Employee employee = getEmployee();
employeeRepository.save(employee);
List<Employee> result = new ArrayList<>();
employeeRepository.findByAge(employee.getAge()).forEach(e -> result.add(e));
assertEquals(result.size(), 1);
}
@Test
public void testFindByEmail() {
Employee employee = getEmployee();
employeeRepository.save(employee);
Employee result = employeeRepository.findByEmail(employee.getEmail());
assertNotNull(result);
}
}