3. gyakorlat

Perzisztencia...

• előfeltételek: MySQL vagy Postgre
• JPA https://spring.io/projects/spring-data-jpa (specifikáció) --> Hibernate (implementáció)
• deps:

  • Tipp: Úgy dependency-k hozzáadásához használjuk a pom.xml-en belül az Alt + Insert billentyűkombinációt.

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
        </dependency>
    

• application.properties https://www.baeldung.com/spring-boot-h2-database#database-configuration

  spring.datasource.url=jdbc:h2:mem:testdb
  spring.datasource.driverClassName=org.h2.Driver
  spring.datasource.username=sa
  spring.datasource.password=sa
  spring.jpa.database-platform=org.hibernate.dialect.H2Dialect
  

• Hikari Pooling

• http://localhost:8080/h2-console
  • JDBC URL az app.props-ból

  • Tipp: IntelliJ > Database fül > Conn-type: In-memory

• Contact model:
  • @Entity
  • @Id
• csekkolni a h2-console-on
• @Table(name = "CONTACT_TABLE")
• @Column(name = "name_col", nullable = false) vs. @NotNull

  package hu.suaf.contacts.model;
  
  import lombok.Data;
  
  import javax.persistence.*;
  import javax.validation.constraints.*;
  import java.util.Date;
  
  @Data
  @Entity
  @Table(name = "CONTACT_TABLE")
  public class Contact {
  
      @Id
      @GeneratedValue(strategy = GenerationType.AUTO)
      private Long id;
  
      @NotEmpty(message = "Name cannot be empty")
      @Size(min = 3, message = "Name must be at least 3 characters long")
      @Column(name = "name_col", nullable = false)
      private String name;
  
      @NotNull
      private String phone;
  
      @NotEmpty(message = "Email cannot be empty")
      @Email(message = "Must be a well-formed email")
      private String email;
      private String address;
  
      @NotNull(message = "Birth date cannot be empty")
      @Past(message = "Must be a past date")
      private Date birthDate;
  
      @PastOrPresent
      private Date createdAt;
  
      @ManyToOne
      @JoinColumn(name = "group_id")
      private ContactGroup contactGroup;
  
  }
  

• új entity:
  • Group --> neve miatt elszáll
    • id, name
  • ContactGroup vagy @Table

    package hu.suaf.contacts.model;
    
    import javax.persistence.Entity;
    import javax.persistence.Id;
    import javax.persistence.OneToMany;
    import java.util.List;
    
    @Entity
    public class ContactGroup {
    
        @Id
        private long id;
    
        private String name;
    
        @OneToMany
        private List<Contact> contacts;
    
    }
    

• Contact-ban kapcsolatok
  • @OneToOne
  • @OneToMany
  • @ManyToOne
  • @ManyToMany
  • extrák:
    • @JoinColumn
    • @JoinTable
  • Group-ban a visszafelé irány (demo, majd kikommentez)
    • List contacts
  • class ContactRepository
    • interface ContactRepository extends JpaRepository<Contact, Long>
    • < típus, id >

      package hu.suaf.contacts.repository;
      
      import hu.suaf.contacts.model.Contact;
      import org.springframework.data.jpa.repository.JpaRepository;
      import org.springframework.stereotype.Repository;
      
      @Repository
      public interface ContactRepository extends JpaRepository<Contact, Long> {
      
      }
      

  • a ContactService-ben helyettesítsük be az új metódusokat
    • az addContact és a saveContact összevonása

      package hu.suaf.contacts.service;
      
      import hu.suaf.contacts.model.Contact;
      import hu.suaf.contacts.repository.ContactRepository;
      import lombok.extern.slf4j.Slf4j;
      import org.springframework.beans.factory.annotation.Autowired;
      import org.springframework.stereotype.Service;
      
      import java.util.List;
      
      @Service
      @Slf4j
      public class ContactService {
      
          private ContactRepository contactRepository;
      
          @Autowired
          public void setContactRepository(ContactRepository contactRepository) {
              this.contactRepository = contactRepository;
          }
      
          public void saveContact(Contact c){
              contactRepository.save(c);
              log.info("Contact added: " + c.toString());
          }
      
          public List<Contact> getContacts(){
              return contactRepository.findAll();
          }
      
          public void deleteContact(long id){
              contactRepository.deleteById(id);
              log.info("Contact deleted with id: " + Long.toString(id));
          }
      
          public Contact getContactById(long id) {
              return contactRepository.findById(id).orElse(null);
          }
      
      }
      

  • auto adat beszúrás
    • resources-ban: data.sql vagy schema.sql

Profilok...

• resources-ban:
  • application-dev.properties:

    spring.datasource.url=jdbc:h2:mem:testdb
    spring.datasource.driverClassName=org.h2.Driver
    spring.datasource.username=sa
    spring.datasource.password=sa
    spring.jpa.database-platform=org.hibernate.dialect.H2Dialect
    

  • application-prod.properties:
    • Postgre: https://dzone.com/articles/bounty-spring-boot-and-postgresql-database
    • MySQL: https://spring.io/guides/gs/accessing-data-mysql/

      spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.PostgreSQLDialect
      spring.datasource.url=jdbc:postgresql://localhost:5432/testdb
      spring.datasource.username=user
      spring.datasource.password=user
      
      spring.jpa.hibernate.ddl-auto=update
      

  • spring.profiles.active=prod

    • Tipp: IntelliJ > run config > active profiles

  • pom.xml:

    <dependency>
        <groupId>org.postgresql</groupId>
        <artifactId>postgresql</artifactId>
    </dependency>
    

Feladat

Egészítsük ki a Contact Create form-ot a group megadásának lehetőségével, valamint készétsük el a ContactGroup CRUD műveleteihez szükséges felületeket/controller-eket/stb.

További anyagok

A gyakorlat anyagáról készült videó:

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Utolsó frissítés: 2021-09-29 22:22:18