阅读副本和Spring Data第2部分：配置基础项目

女爷i 2023-02-25 04:00 31阅读 0赞

在上一篇文章中，我们使用相同的数据设置了多个PostgreSQL实例。  
下一步将是使用这两个服务器来配置spring项目。

![format_png][]

如前所述，由于我们使用完全相同的数据库，因此我们将使用[Spring Boot JPA][]帖子中的一些代码。

这将是我们的gradle构建文件

plugins { 
         id 'org.springframework.boot' version '2.1.9.RELEASE' 
         id 'io.spring.dependency-management' version '1.0.8.RELEASE' 
         id 'java'  }  group = 'com.gkatzioura'  version = '0.0.1-SNAPSHOT'  sourceCompatibility = '1.8'  repositories { 
         mavenCentral()  }  dependencies { 
         implementation 'org.springframework.boot:spring-boot-starter-data-jpa' 
         implementation 'org.springframework.boot:spring-boot-starter-web' 
         implementation "org.postgresql:postgresql:42.2.8" 
         testImplementation 'org.springframework.boot:spring-boot-starter-test'  }

现在，让我们基于上一个博客上创建的表来创建模型。

package com.gkatzioura.springdatareadreplica.entity;  import javax.persistence.Column;  import javax.persistence.Entity;  import javax.persistence.GeneratedValue;  import javax.persistence.GenerationType;  import javax.persistence.Id;  import javax.persistence.Table;  @Entity  @Table (name = "employee" , catalog= "spring_data_jpa_example" )  public class Employee { 
         @Id 
         @Column (name = "id" ) 
         @GeneratedValue (strategy = GenerationType.IDENTITY) 
         private Long id; 
         @Column (name = "firstname" ) 
         private String firstName; 
         @Column (name = "lastname" ) 
         private String lastname; 
         @Column (name = "email" ) 
         private String email; 
         @Column (name = "age" ) 
         private Integer age; 
         @Column (name = "salary" ) 
         private Integer salary; 
         public Long getId() { 
             return id; 
         } 
         public void setId(Long id) { 
             this .id = id; 
         } 
         public String getFirstName() { 
             return firstName; 
         } 
         public void setFirstName(String firstName) { 
             this .firstName = firstName; 
         } 
         public String getLastname() { 
             return lastname; 
         } 
         public void setLastname(String lastname) { 
             this .lastname = lastname; 
         } 
         public String getEmail() { 
             return email; 
         } 
         public void setEmail(String email) { 
             this .email = email; 
         } 
         public Integer getAge() { 
             return age; 
         } 
         public void setAge(Integer age) { 
             this .age = age; 
         } 
         public Integer getSalary() { 
             return salary; 
         } 
         public void setSalary(Integer salary) { 
             this .salary = salary; 
         }  }

下一步是创建spring数据存储库。

package com.gkatzioura.springdatareadreplica.repository;  import org.springframework.data.jpa.repository.JpaRepository;  import com.gkatzioura.springdatareadreplica.entity.Employee;  public interface EmployeeRepository extends JpaRepository<Employee,Long> {  }

另外，我们将添加一个控制器。

package com.gkatzioura.springdatareadreplica.controller;  import java.util.List;  import org.springframework.web.bind.annotation.RequestMapping;  import org.springframework.web.bind.annotation.RestController;  import com.gkatzioura.springdatareadreplica.entity.Employee;  import com.gkatzioura.springdatareadreplica.repository.EmployeeRepository;  @RestController  public class EmployeeContoller { 
         private final EmployeeRepository employeeRepository; 
         public EmployeeContoller(EmployeeRepository employeeRepository) { 
             this .employeeRepository = employeeRepository; 
         } 
         @RequestMapping ( "/employee" ) 
         public List<Employee> getEmployees() { 
             return employeeRepository.findAll(); 
         }  }

它所要做的只是在application.yaml中添加正确的属性。

spring: 
       datasource: 
         platform: postgres 
         driverClassName: org.postgresql.Driver 
         username: db-user 
         password: your-password 
         url: jdbc:postgresql: //127.0.0.2:5432/postgres url: jdbc:postgresql: //127.0.0.2:5432/postgres url: jdbc:postgresql:

如今，Spring Boot使得不必理会任何JPA配置。

这是运行该应用程序所需的全部。 应用程序运行后，只需尝试获取员工即可。

curl http: //localhost :8080 /employee

如您所见，我们没有进行任何JPA配置。 由于Spring Boot 2指定数据库url就足以启动自动配置并为您完成所有此配置。

但是，在我们的情况下，我们希望具有多个数据源和实体管理器配置。 在下一篇[文章中，][Link 1]我们将为我们的应用程序配置实体管理器。

> 翻译自: [https://www.javacodegeeks.com/2019/10/read-replicas-and-spring-data-configuring-the-base-project.html][https_www.javacodegeeks.com_2019_10_read-replicas-and-spring-data-configuring-the-base-project.html]

[format_png]: /images/20230209/f5c602bb9cbc4a759d83967342fb6cca.png
[Spring Boot JPA]: https://egkatzioura.com/2016/06/02/spring-boot-and-spring-data-jpa-integration/
[Link 1]: https://egkatzioura.com/2019/10/10/read-replicas-and-spring-data-part-3-configuring-two-entity-managers/
[https_www.javacodegeeks.com_2019_10_read-replicas-and-spring-data-configuring-the-base-project.html]: https://www.javacodegeeks.com/2019/10/read-replicas-and-spring-data-configuring-the-base-project.html