Mapping

Type Mapping:

Annotation mapping
XML mapping
Dynamic mapping

Annotation mapping

/**
 * Single financial operation.
 */
@SuppressWarnings("PMD")
@ToString
@Entity
@Table(name = "journal",
        indexes = {@Index(name = "j_account_idx", columnList = "account_id", unique = false)},
        uniqueConstraints = {@UniqueConstraint(columnNames = {"id", "account_id"})})
@SecondaryTable(name = "operations_details",
        pkJoinColumns = @PrimaryKeyJoinColumn(name = "op_id", referencedColumnName = "id"))
public class Operation {
    /**
     * Operation id.
     */
    @Id
    @GeneratedValue
    @Getter
    @Setter
    @Column(name = "id", nullable = false, updatable = false)
    private Long rowId;

    /**
     * Related transaction id.
     *
     * Single transaction could have
     * more then one operations.
     */
    @Getter
    @Setter
    @Column(name = "trxId", nullable = false, updatable = false)
    private Long id;

    /**
     * Operation's account.
     */
    @Getter
    @Setter
    @Column(nullable = false, updatable = false)
    private Integer accountId;

    /**
     * Operation's amount.
     */
    @Getter
    @Setter
    @Column(nullable = false, updatable = false, scale = 2, precision = 10)
    private BigDecimal amount;

    /**
     * Operation's timestamp.
     */
    @Getter
    @Setter
    @Column(nullable = false, updatable = false)
    private ZonedDateTime timestamp;

    /**
     * Optional operation description.
     */
    @Getter
    @Setter
    @Column(table = "operations_details", length = 64)
    private String description;

    /**
     * Optional operation code.
     */
    @Getter
    @Setter
    @Column(table = "operations_details")
    private Integer opCode;
}

Configuration

<hibernate-configuration>
    <session-factory>
        <property name="hibernate.hbm2ddl.auto">update</property>
        <property name="hibernate.dialect">org.hibernate.dialect.H2Dialect</property>
        <property name="hibernate.connection.url">jdbc:h2:mem:test</property>

        <mapping class="ru.easyjava.data.hibernate.entity.Operation"/>
    </session-factory>
</hibernate-configuration>

XML mapping

<hibernate-mapping package="ru.easyjava.data.hibernate.entity">
    <class name="Person" abstract="true" table="PERSONS">
        <id name="id" type="int" column="id">
            <generator class="native"/>
        </id>
        <property name="firstName" type="string" column="FIRST_NAME"/>
        <property name="lastName" type="string" column="LAST_NAME"/>
        <property name="dob" type="timestamp" column="DOB"/>
        <one-to-one name="passport" class="ru.easyjava.data.hibernate.entity.Passport" cascade="save-update"/>
        <many-to-one name="primaryAddress" class="ru.easyjava.data.hibernate.entity.Address">
        <column name="PRIMARY_ADDRESS"/>
        </many-to-one>
            <set name="workingPlaces" table="WORKERS" inverse="false" lazy="true" cascade="all">
            <key column="PERSON_ID"/>
            <many-to-many column="COMPANY_ID" class="ru.easyjava.data.hibernate.entity.Company"/>
        </set>
    </class>
</hibernate-mapping>

Configuration

<hibernate-configuration>
    <session-factory>
        <property name="hibernate.hbm2ddl.auto">update</property>
        <property name="hibernate.dialect">org.hibernate.dialect.H2Dialect</property>
        <property name="hibernate.connection.url">jdbc:h2:mem:test</property>

        <mapping resource="Passport.hbm.xml"/>
        <mapping resource="Address.hbm.xml"/>
        <mapping resource="Company.hbm.xml"/>
        <mapping resource="Person.hbm.xml"/>
    </session-factory>
</hibernate-configuration>

Dynamic mapping

<hibernate-mapping>
    <class entity-name="Passport">
        <id name="id" type="long" column="ID">
            <generator class="native"/>
        </id>
        <property name="series" column="SERIES" type="string"/>
        <property name="no" column="NO" type="string"/>
        <property name="issueDate" column="ISSUE_DATE" type="timestamp"/>
    </class>
</hibernate-mapping>

Configuration

<hibernate-configuration>
    <session-factory>
        <property name="hibernate.hbm2ddl.auto">update</property>
        <property name="hibernate.dialect">org.hibernate.dialect.H2Dialect</property>
        <property name="hibernate.connection.url">jdbc:h2:mem:test</property>
        <property name="default_entity_mode">dynamic-map</property>

        <mapping resource="Passport.hbm.xml"/>
    </session-factory>
</hibernate-configuration>

Basics Mapping

Entity Mapping

@Entity
@Table
@DynamicInsert (default: true)
@DynamicUpdate (default: true)
@SelectBeforeUpdate (deafult: true)
@Polymorphism (default: implicit)

Entity Mapping

@ClassPersister
@OptimisticLoking (default: version)
@Proxy(lazy = true, proxyClass = "com.some.package.SomeProxyClass.java")
@BatchSize (default: 1)
@Check
@Immutable

Entity Mapping

@Where
@DiscriminatorValue
@Subselct("Some SQL query")
@RowId

Entity Fields Mapping

@Column
@Type
@NotNull
@Formula
@Enumearted

`@Column`

name
unique
nullable
insertable
updatable

`@Column`

columnDifinition
table
length
precision
scale

`@Enumerated`

Нужна для маппинга объектов типа enum
Можно указать сохранять enum как:
- строку (EnumType.STRING)
- целое число (EnumType.ORDINAL)

`@Enumerated`

@Enumerated(EnumType.STRING)
private Gender gender;

Table and Column Naming Strategy

public class DefaultNamingStrategy implements PhysicalNamingStrategy {
    @Override
    public Identifier toPhysicalCatalogName(final Identifier identifier,
            final JdbcEnvironment jdbcEnv) {
        return convertToSnakeCase(identifier);
    }

    @Override
    public Identifier toPhysicalColumnName(final Identifier identifier,
            final JdbcEnvironment jdbcEnv) {
        return convertToSnakeCase(identifier);
    }

    @Override
    public Identifier toPhysicalSchemaName(final Identifier identifier,
            final JdbcEnvironment jdbcEnv) {
        return convertToSnakeCase(identifier);
    }

    @Override
    public Identifier toPhysicalSequenceName(final Identifier identifier,
            final JdbcEnvironment jdbcEnv) {
        return convertToSnakeCase(identifier);
    }

    @Override
    public Identifier toPhysicalTableName(final Identifier identifier,
            final JdbcEnvironment jdbcEnv) {
        return convertToSnakeCase(identifier);
    }

    private Identifier convertToSnakeCase(final Identifier identifier) {
        final String regex = "([a-z])([A-Z])";
        final String replacement = "$1_$2";
        final String newName = identifier.getText()
          .replaceAll(regex, replacement)
          .toLowerCase();
        return Identifier.toIdentifier(newName);
    }
}

Table and Column Naming Strategy

Configuration conf = new Configuration()
        .configure()
        .setNamingStrategy(new DefaultNamingStrategy());
        .buildSessionFactory();

Table and Column Naming Strategy

<hibernate-configuration>
    <session-factory>
        <property name="hibernate.physical_naming_strategy">
            com.rakovers.course.datapersistence.dal.config.DefaultNamingStrategy
        </property>
    </session-factory>
</hibernate-configuration>

Object Identity and Equality

Object Identity
Object Equality
Database Identity

Object Identity and Equality

@Id
@Type
@Column
@Access
@GeneratedValue

`GenerationType`

AUTO
TABLE
SEQUENCE
IDENTITY

`org.hibernate.id.IdentifierGenerator`

uuid2 - UUIDGenerator
guid - GUIDGenerator
uuid - UUIDHexGenerator
uuid.hex - UUIDHexGenerator
assigned - Assigned
identity - IdentityGenerator
select - SelectGenerator

`org.hibernate.id.IdentifierGenerator`

sequence - SequenceStyleGenerator
seqhilo - SequenceHiLoGenerator
increment - IncrementGenerator
foreign - ForeignGenerator
sequence-identity - SequenceIdentityGenerator
enhanced-sequence - SequenceStyleGenerator
enhanced-table- TableGenerator

Component Mapping

Entity - объект, наделенный уникальным идентификатором
Component - объект, без идентификатора

Component Mapping

@Embedded
@Embeddable

Mapping of Inheritance

Three inheritance mapping strategies:

Table Per Hierarchy
Table Per Concrete class
Table Per Subclass

Table Per Hierarchy

@Entity
@Table(name = "employees")
@Inheritance(strategy = InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(name = "employee_type", discriminatorType = DiscriminatorType.STRING)
@NoArgsConstructor
@ToString(callSuper = true)
public abstract class EmployeeEntity extends BaseEntity {
    @Column(name = "name")
    @Getter
    @Setter
    private String name;
}

Table Per Hierarchy

@Entity
@Table(name = "managers")
@ToString(callSuper = true)
@DiscriminatorValue("manager")
public class ManagerEntity extends EmployeeEntity {
    @Getter
    @Setter
    @Column(name = "number_of_idle_hours", nullable = false)
    private Integer numberOfIdleHours;
}

Table Per Concrete class

@Entity
@Table(name = "employees")
@Inheritance(strategy = InheritanceType.TABLE_PER_CLASS)
@NoArgsConstructor
@ToString(callSuper = true)
public abstract class EmployeeEntity extends BaseEntity {
    @Column(name = "name")
    @Getter
    @Setter
    private String name;
}

Table Per Concrete class

@Entity
@Table(name = "managers")
@ToString(callSuper = true)
@AttributeOverrides({
        @AttributeOverride(name = "id", column = @Column(name = "id")),
        @AttributeOverride(name = "name", column = @Column(name = "name"))
})
public class ManagerEntity extends EmployeeEntity {
    @Getter
    @Setter
    @Column(name = "number_of_idle_hours", nullable = false)
    private Integer numberOfIdleHours;
}

Table Per Subclass

@Entity
@Table(name = "employees")
@Inheritance(strategy = InheritanceType.JOINED)
@NoArgsConstructor
@ToString(callSuper = true)
public abstract class EmployeeEntity extends BaseEntity {
    @Column(name = "name")
    @Getter
    @Setter
    private String name;
}

Table Per Subclass

@Entity
@Table(name = "managers")
@ToString(callSuper = true)
@PrimaryKeyJoinColumn(name = "employee_id")
public class ManagerEntity extends EmployeeEntity {
    @Getter
    @Setter
    @Column(name = "number_of_idle_hours", nullable = false)
    private Integer numberOfIdleHours;
}