| /******************************************************************************* |
| * Copyright (c) 2008 - 2013 Oracle Corporation. All rights reserved. |
| * |
| * This program and the accompanying materials are made available under the |
| * terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0 |
| * which accompanies this distribution. |
| * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html |
| * and the Eclipse Distribution License is available at |
| * http://www.eclipse.org/org/documents/edl-v10.php. |
| * |
| * Contributors: |
| * Linda DeMichiel - Java Persistence 2.1 |
| * Linda DeMichiel - Java Persistence 2.0 |
| * |
| ******************************************************************************/ |
| package javax.persistence; |
| |
| import java.lang.annotation.Target; |
| import java.lang.annotation.Retention; |
| import javax.persistence.CascadeType; |
| import static java.lang.annotation.ElementType.FIELD; |
| import static java.lang.annotation.ElementType.METHOD; |
| import static java.lang.annotation.RetentionPolicy.RUNTIME; |
| import static javax.persistence.FetchType.LAZY; |
| |
| /** |
| * Specifies a many-valued association with many-to-many multiplicity. |
| * |
| * <p> Every many-to-many association has two sides, the owning side |
| * and the non-owning, or inverse, side. The join table is specified |
| * on the owning side. If the association is bidirectional, either |
| * side may be designated as the owning side. If the relationship is |
| * bidirectional, the non-owning side must use the <code>mappedBy</code> element of |
| * the <code>ManyToMany</code> annotation to specify the relationship field or |
| * property of the owning side. |
| * |
| * <p> The join table for the relationship, if not defaulted, is |
| * specified on the owning side. |
| * |
| * <p> The <code>ManyToMany</code> annotation may be used within an |
| * embeddable class contained within an entity class to specify a |
| * relationship to a collection of entities. If the relationship is |
| * bidirectional and the entity containing the embeddable class is the |
| * owner of the relationship, the non-owning side must use the |
| * <code>mappedBy</code> element of the <code>ManyToMany</code> |
| * annotation to specify the relationship field or property of the |
| * embeddable class. The dot (".") notation syntax must be used in the |
| * <code>mappedBy</code> element to indicate the relationship |
| * attribute within the embedded attribute. The value of each |
| * identifier used with the dot notation is the name of the respective |
| * embedded field or property. |
| * |
| * <pre> |
| * |
| * Example 1: |
| * |
| * // In Customer class: |
| * |
| * @ManyToMany |
| * @JoinTable(name="CUST_PHONES") |
| * public Set<PhoneNumber> getPhones() { return phones; } |
| * |
| * // In PhoneNumber class: |
| * |
| * @ManyToMany(mappedBy="phones") |
| * public Set<Customer> getCustomers() { return customers; } |
| * |
| * Example 2: |
| * |
| * // In Customer class: |
| * |
| * @ManyToMany(targetEntity=com.acme.PhoneNumber.class) |
| * public Set getPhones() { return phones; } |
| * |
| * // In PhoneNumber class: |
| * |
| * @ManyToMany(targetEntity=com.acme.Customer.class, mappedBy="phones") |
| * public Set getCustomers() { return customers; } |
| * |
| * Example 3: |
| * |
| * // In Customer class: |
| * |
| * @ManyToMany |
| * @JoinTable(name="CUST_PHONE", |
| * joinColumns= |
| * @JoinColumn(name="CUST_ID", referencedColumnName="ID"), |
| * inverseJoinColumns= |
| * @JoinColumn(name="PHONE_ID", referencedColumnName="ID") |
| * ) |
| * public Set<PhoneNumber> getPhones() { return phones; } |
| * |
| * // In PhoneNumberClass: |
| * |
| * @ManyToMany(mappedBy="phones") |
| * public Set<Customer> getCustomers() { return customers; } |
| * </pre> |
| * |
| * @see JoinTable |
| * |
| * @since Java Persistence 1.0 |
| */ |
| @Target({METHOD, FIELD}) |
| @Retention(RUNTIME) |
| public @interface ManyToMany { |
| |
| /** |
| * (Optional) The entity class that is the target of the |
| * association. Optional only if the collection-valued |
| * relationship property is defined using Java generics. Must be |
| * specified otherwise. |
| * |
| * <p> Defaults to the parameterized type of |
| * the collection when defined using generics. |
| */ |
| Class targetEntity() default void.class; |
| |
| /** |
| * (Optional) The operations that must be cascaded to the target |
| * of the association. |
| * |
| * <p> When the target collection is a {@link java.util.Map |
| * java.util.Map}, the <code>cascade</code> element applies to the |
| * map value. |
| * |
| * <p> Defaults to no operations being cascaded. |
| */ |
| CascadeType[] cascade() default {}; |
| |
| /** (Optional) Whether the association should be lazily loaded or |
| * must be eagerly fetched. The EAGER strategy is a requirement on |
| * the persistence provider runtime that the associated entities |
| * must be eagerly fetched. The LAZY strategy is a hint to the |
| * persistence provider runtime. |
| */ |
| FetchType fetch() default LAZY; |
| |
| /** |
| * The field that owns the relationship. Required unless |
| * the relationship is unidirectional. |
| */ |
| String mappedBy() default ""; |
| } |