birt barcode tool C.2.4 Defining domain relationships in Java

Make ECC200 in Java C.2.4 Defining domain relationships

These annotations are used to define one-to-one, one-to-many and many-tomany relationships between entities. javax.persistence.OneToOne Specifies a one-to-one entity association.

@Target({METHOD, FIELD}) @Retention(RUNTIME) Entity class if not public @interface OneToOne { Java generics Class targetEntity() default void.class; CascadeType[] cascade() default {}; FetchType fetch() default EAGER; Relationship boolean optional() default true; owner String mappedBy() default ""; } public enum CascadeType { ALL, PERSIST, MERGE, REMOVE, REFRESH }; public enum FetchType { LAZY, EAGER };

@Target({METHOD, FIELD}) @Retention(RUNTIME) public @interface ManyToOne { Class targetEntity() default void.class; CascadeType[] cascade() default {};

FetchType fetch() default EAGER; boolean optional() default true; }

@Target({METHOD, FIELD}) @Retention(RUNTIME) Entity class if not public @interface OneToMany { Java generic Class targetEntity() default void.class; CascadeType[] cascade() default {}; FetchType fetch() default LAZY; Relationship owner String mappedBy() default ""; }

@Target({METHOD, FIELD}) @Retention(RUNTIME) Entity class if not public @interface ManyToMany { Java generic Class targetEntity() default void.class; CascadeType[] cascade() default {}; FetchType fetch() default LAZY; Relationship owner String mappedBy() default ""; }

These annotations are used to map entity relations to the database. javax.persistence.JoinColumn Denotes a mapping column for an entity association.

@Target({METHOD, FIELD}) @Retention(RUNTIME) public @interface JoinColumn { String name() default ""; String referencedColumnName() default ""; boolean unique() default false; boolean nullable() default true; boolean insertable() default true; boolean updatable() default true; String columnDefinition() default ""; String table() default ""; }

javax.persistence.JoinColumns Denotes a mapping column for an entity association when a composite key is used.

@Target({METHOD, FIELD}) @Retention(RUNTIME) public @interface JoinColumns {

JoinColumn[] value(); }

javax.persistence.PrimaryKeyJoinColumn Denotes the primary key column that is used as a foreign key to join to another table. It is used in one-to-one relationships and the joined subclass inheritance strategy.

@Target({TYPE, METHOD, FIELD}) @Retention(RUNTIME) public @interface PrimaryKeyJoinColumn { Key in current table String name() default ""; String referencedColumnName() default ""; String columnDefinition() default ""; Column DDL }

javax.persistence.PrimaryKeyJoinColumns Specifies composite primary keys used as foreign key to join to another table.

@Target({TYPE, METHOD, FIELD}) @Retention(RUNTIME) public @interface PrimaryKeyJoinColumns { PrimaryKeyJoinColumn[] value(); }

javax.persistence.JoinTable Specifies a join table used in a one-to-many or many-to-many association.

@Target({METHOD, FIELD}) @Retention(RUNTIME) public @interface JoinTable { String name() default ""; Table catalog String catalog default ""; Join column(s) in String schema default ""; Table schema owning side JoinColumn[] joinColumns default {}; JoinColumn[] inverseJoinColumns default {}; Join column(s) in UniqueConstraint[] uniqueConstraints default {}; inverse side }

javax.persistence.AssociationOverride Overrides a many-to-one or one-to-one mapping of property or field for an entity relationship.

@Target({TYPE, METHOD, FIELD}) @Retention(RUNTIME) public @interface AssociationOverride { String name default ""; JoinColumn[] joinColumns default {}; }

javax.persistence.AssociationOverrides Overrides mappings of multiple many-to-one or one-to-one relationship properties or fields.

@Target({TYPE, METHOD, FIELD}) @Retention(RUNTIME) public @interface AssociationOverrides { AssociationOverride[] value(); }

javax.persistence.OrderBy Specifies ordering of a collection-valued association such as one-to-many and many-to-many when it is retrieved.

@Target({METHOD, FIELD}) @Retention(RUNTIME) public @interface OrderBy { String value() default ""; }

javax.persistence.MapKey Specifies the mapping keys for an entity association of type java.util.Map. This annotation is not discussed in this book. We encourage you to explore it on your own.

@Target({METHOD, FIELD}) @Retention(RUNTIME) public @interface MapKey { String name() default ""; }

The following annotations are used to map OO inheritance to relational database tables. javax.persistence.Inheritance Defines the inheritance mapping strategy for entities in the entity hierarchy.

@Target({TYPE}) @Retention(RUNTIME) public @interface Inheritance { InheritanceType strategy() default SINGLE_TABLE; } public enum InheritanceType { SINGLE_TABLE, JOINED, TABLE_PER_CLASS };

javax.persistence.DiscriminatorColumn Defines the discriminator column used when the single-table or joined inheritance strategy is used.

@Target({TYPE}) @Retention(RUNTIME) public @interface DiscriminatorColumn { String name() default "DTYPE"; DiscriminatorType discriminatorType() default STRING; String columnDefinition() default ""; Column DDL int length() default 31; } public enum DiscriminatorType { STRING, CHAR, INTEGER };

javax.persistence.DiscriminatorValue Specifies the value for a discriminator column for storing the entity type when the single-table or joined inheritance strategy is used.

@Target({TYPE}) @Retention(RUNTIME) public @interface DiscriminatorValue { String value(); }