java Spring JPA - 按 EmbeddedId 部分查找
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Spring JPA - Find By EmbeddedId partially
提问by Amit Phaltankar
Below code is for demo purpose only.
以下代码仅用于演示目的。
My Entitybean looks like this
我的实体bean 看起来像这样
@Entity
class Employee {
@EmbeddedId
private EmployeeKey employeeKey;
private String firstName;
private String lastName;
// Other fields
// Getter and Setters
}
The Embeddableclass:
该嵌入式类：
@Embeddable
class EmployeeKey implements Serializable {
private int employeeId;
private String branchName;
private String departmentName;
//Getter and Setters
}
I can write JPARepositoryinterface method to find Employees by the EmbeddedId that returns me results as well.
我可以编写JPARepository接口方法，通过也返回结果的 EmbeddedId 来查找员工。
interface EmployeeRepository extends JpaRepository<Employee, EmployeeKey> {
List<Employee> findByEmployeeKey(EmployeeKey employeeKey);
}
Question:Suppose, while querying I have employeeIdand branchNameonly, and I don't want to put filter on departmentName
问题：假设，在查询时我只有员工ID和分支名称，我不想在部门名称上放置过滤器
- In such cases how can I write my Repository method
- Does JPA have something in-build for such scenario?
- 在这种情况下，我该如何编写我的 Repository 方法
- JPA 是否有针对这种情况的内置内容？
采纳答案by Amit Phaltankar
Here is how it worked for me.
这是它对我的工作方式。
@Ketrox's answer is absolutely correct and works fine. But in my real scenario I had 6 fields to search by and which resulted in an 120+ characters long method name. (Something like below)
@Ketrox 的回答绝对正确并且工作正常。但在我的真实场景中，我有 6 个字段可供搜索，这导致了 120 多个字符长的方法名称。（类似于下面的东西）
List<Employee> findByEmployeeKeyField1AndEmployeeKeyField2AndEmployeeKeyField3AndEmployeeKeyField4AndEmployeeKeyField5AndEmployeeKeyField6(String field1, String field2, String field3, String field4, String field5, String field6);
Which is certainly not good enough to read and more than good enough to make codenarcunhappy.
这当然不足以阅读，而且足以让codenarc不高兴。
Finally I used find by example and that turned out to be really pleasant solution.
最后，我使用了 find by example，结果证明这是一个非常令人愉快的解决方案。
Repository:
存储库：
//skipped lines
import org.springframework.data.domain.Example
//skipped lines
interface EmployeeRepository extends JpaRepository<Employee, EmployeeKey>{
List<Employee> findAll(Example<Employee> employee);
}
Usage:
用法：
// Prepare Employee key with all available search by keys (6 in my case)
EmplyeeKey key = new EmplyeeKey();
key.setField1("field1_value");
key.setField2("field2_value");
//Setting remaining 4 fields
// Create new Employee ans set the search key
Employee employee = new Employee();
employee.setEmployeeKey(key);
// Call the findAll by passing an Example of above Employee object
List<Employee> result = employeeRepository.findAll(Example.of(employee));
I have elaborated the search by Spring Data JPA find by @EmbeddedId Partially
我已经通过 @EmbeddedId 部分详细说明了Spring Data JPA find 的搜索
回答by ketrox
List<Employee> findByEmployeeKeyEmployeeIdAndEmployeeKeyDepartmentName(int Id,String name);
Should work Have a look at query derivation
应该工作看看查询派生
