001/*
002 * Portions of this software was developed by employees of the National Institute
003 * of Standards and Technology (NIST), an agency of the Federal Government and is
004 * being made available as a public service. Pursuant to title 17 United States
005 * Code Section 105, works of NIST employees are not subject to copyright
006 * protection in the United States. This software may be subject to foreign
007 * copyright. Permission in the United States and in foreign countries, to the
008 * extent that NIST may hold copyright, to use, copy, modify, create derivative
009 * works, and distribute this software and its documentation without fee is hereby
010 * granted on a non-exclusive basis, provided that this notice and disclaimer
011 * of warranty appears in all copies.
012 *
013 * THE SOFTWARE IS PROVIDED 'AS IS' WITHOUT ANY WARRANTY OF ANY KIND, EITHER
014 * EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, ANY WARRANTY
015 * THAT THE SOFTWARE WILL CONFORM TO SPECIFICATIONS, ANY IMPLIED WARRANTIES OF
016 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND FREEDOM FROM
017 * INFRINGEMENT, AND ANY WARRANTY THAT THE DOCUMENTATION WILL CONFORM TO THE
018 * SOFTWARE, OR ANY WARRANTY THAT THE SOFTWARE WILL BE ERROR FREE.  IN NO EVENT
019 * SHALL NIST BE LIABLE FOR ANY DAMAGES, INCLUDING, BUT NOT LIMITED TO, DIRECT,
020 * INDIRECT, SPECIAL OR CONSEQUENTIAL DAMAGES, ARISING OUT OF, RESULTING FROM,
021 * OR IN ANY WAY CONNECTED WITH THIS SOFTWARE, WHETHER OR NOT BASED UPON WARRANTY,
022 * CONTRACT, TORT, OR OTHERWISE, WHETHER OR NOT INJURY WAS SUSTAINED BY PERSONS OR
023 * PROPERTY OR OTHERWISE, AND WHETHER OR NOT LOSS WAS SUSTAINED FROM, OR AROSE OUT
024 * OF THE RESULTS OF, OR USE OF, THE SOFTWARE OR SERVICES PROVIDED HEREUNDER.
025 */
026
027package gov.nist.secauto.metaschema.databind.model.annotations;
028
029import static java.lang.annotation.ElementType.ANNOTATION_TYPE;
030import static java.lang.annotation.RetentionPolicy.RUNTIME;
031
032import java.lang.annotation.Documented;
033import java.lang.annotation.Retention;
034import java.lang.annotation.Target;
035import java.util.regex.Pattern;
036
037import edu.umd.cs.findbugs.annotations.NonNull;
038
039/**
040 * Identifies a Metapath expression referencing a value that is used in
041 * generating a key as part of a {@link IsUnique}, {@link Index}, or
042 * {@link IndexHasKey} constraint annotation.
043 */
044@Documented
045@Retention(RUNTIME)
046@Target(ANNOTATION_TYPE)
047public @interface KeyField {
048  /**
049   * An optional metapath that points to the target flag or field value that the
050   * key applies to. If omitted the target will be ".", which means the target is
051   * the value of the {@link BoundFlag}, {@link BoundField} or
052   * {@link MetaschemaFieldValue} annotation the constraint appears on. In the
053   * prior case, this annotation may only appear on a {@link BoundField} if the
054   * field has no flags, which results in a {@link BoundField} annotation on a
055   * field instance with a scalar, data type value.
056   *
057   * @return the target metapath
058   */
059  @NonNull
060  String target() default ".";
061
062  /**
063   * Retrieve an optional pattern to use to retrieve the value. If
064   * non-{@code null}, the first capturing group is used to retrieve the value.
065   * This must be a pattern that can compile using
066   * {@link Pattern#compile(String)}.
067   *
068   * @return a pattern string or an empty string if no pattern is provided
069   */
070  @NonNull
071  String pattern() default "";
072
073  /**
074   * Any remarks about the key field, encoded as an escaped Markdown string.
075   *
076   * @return an encoded markdown string or an empty string if no remarks are
077   *         provided
078   */
079  @NonNull
080  String remarks() default "";
081}