Spring Boot JPA - 命名查询

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有时会出现这样的情况，我们需要一个自定义查询来完成一个测试用例。我们可以使用@NamedQuery注释在实体类中指定命名查询，然后在存储库中声明该方法。下面是一个例子。

我们在JPA 自定义方法章节的存储库中添加了自定义方法。现在让我们使用 @NamedQuery 添加另一个方法并测试它。

实体-Entity.java

以下是 Employee 的默认代码。它代表一个包含 id、name、age 和 email 列的 Employee 表。

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;
   }
}

存储库-EmployeeRepository.java

添加一种按姓名和年龄查找员工的方法。

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上述方法的实现。让我们通过在测试文件中添加测试用例来测试添加的方法。下面文件的最后两个方法测试添加的命名查询方法。

以下是EmployeeRepositoryTest的完整代码。

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);	     
   }
}

运行测试用例

在 eclipse 中右键单击该文件并选择“运行 JUnit 测试”并验证结果。