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Neo4j-OGM's internal Api for connecting different transports.

There is a newer version: 4.0.11

/*
 * Copyright (c) 2002-2016 "Neo Technology,"
 * Network Engine for Objects in Lund AB [http://neotechnology.com]
 *
 * This product is licensed to you under the Apache License, Version 2.0 (the "License").
 * You may not use this product except in compliance with the License.
 *
 * This product may include a number of subcomponents with
 * separate copyright notices and license terms. Your use of the source
 * code for these subcomponents is subject to the terms and
 *  conditions of the subcomponent's license, as noted in the LICENSE file.
 */
package org.neo4j.ogm.annotation;

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

/**
 * Fields and properties marked with this annotation will notify the OGM that they
 * should be used as part of an index and/or for use during lookups and merging.
 *
 * Fields marked with unique=false and primary=true will be ignored.
 *
 * Only one index per class hierarchy may be marked as primary.
 *
 * If index auto generation is turned on then classes containing @Index
 * will be used. Indexes will always be generated with the containing class's label and
 * the annotated property's name.
 *
 * Index generation behaviour can be defined in ogm.properties by
 * defining a property called: indexes.auto and providing
 * a value of:
 * 
 * assert: drop all indexes and constraints then create
 * constraints and indexes on startup. No indexes or constraints will be dropped on
 * shutdown.
 * validate: confirm that the required indexes and constraints
 * defined already exist on startup otherwise abort startup
 * dump: will generate a file in the current directory with the
 * cypher commands to create indexes and constraints. Before doing this it will run the
 * same behaviour as validate.
 * none: do not generate any constraints or indexes
 * [default]
 * 
 *
 * @author Mark Angrish
 */
@Retention(RetentionPolicy.RUNTIME)
@Target(value = ElementType.FIELD)
public @interface Index {

	/**
	 * Indicates whether to apply a unique constraint on this property, defaults to
	 * false.
	 */
	boolean unique() default false;

	/**
	 * Indicates this constraint (unique index) should be used as the key for merges and loading by id.
	 */
	boolean primary() default false;
}