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The Java Persistence API (JPA) : a standard interface-based Java model abstraction of persistence, developed by the JCP.

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/*
 * Copyright (c) 2008, 2009, 2011 Oracle, Inc. 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.
 */
package javax.persistence;

import java.lang.annotation.Retention;
import java.lang.annotation.Target;

import static java.lang.annotation.ElementType.ANNOTATION_TYPE;
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.EAGER;

/**
 * The simplest type of mapping to a database column. The Basic annotation can be applied to a
 * persistent property or instance variable of any of the following types: Java primitive types, wrappers of
 * the primitive types, String, java.math.BigInteger,
 * java.math.BigDecimal, java.util.Date, java.util.Calendar,
 * java.sql.Date, java.sql.Time, java.sql.Timestamp,
 * byte[], Byte[], char[], Character[], enums, and any
 * other type that implements java.io.Serializable.
 * 
 * The use of the Basic annotation is optional for persistent fields and properties of these
 * types. If the Basic annotation is not specified for such a field or property, the default
 * values of the Basic annotation will apply.
 *
 * 
 *    Example 1:
 * 
 *    @Basic
 *    protected String name;
 * 
 *    Example 2:
 * 
 *    @Basic(fetch=LAZY)
 *    protected String getName() { return name; }
 *
 * 
 * @since Java Persistence 1.0
 */
@Target({ANNOTATION_TYPE, METHOD, FIELD})
@Retention(RUNTIME)
public @interface Basic
{

    /**
     * (Optional) Defines whether the value of the field or property should be lazily loaded or must be
     * eagerly fetched. The EAGER strategy is a requirement on the persistence provider runtime
     * that the value must be eagerly fetched. The LAZY strategy is a hint to the persistence
     * provider runtime. If not specified, defaults to EAGER.
     * @return fetch type
     */
    FetchType fetch() default EAGER;

    /**
     * (Optional) Defines whether the value of the field or property may be null. This is a hint and is
     * disregarded for primitive types; it may be used in schema generation. If not specified, defaults to
     * true.
     * @return whether it is optional
     */
    boolean optional() default true;
}