/*

 * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 */

package com.sun.xml.internal.xsom;

import java.util.List;

/**

 * Identity constraint.

 *

 * @author Kohsuke Kawaguchi

 */

public interface XSIdentityConstraint extends XSComponent {

    /**

     * Gets the {@link XSElementDecl} that owns this identity constraint.

     *

     * @return

     *      never null.

     */

    XSElementDecl getParent();

    /**

     * Name of the identity constraint.

     *

     * A name uniquely identifies this {@link XSIdentityConstraint} within

     * the namespace.

     *

     * @return

     *      never null.

     */

    String getName();

    /**

     * Target namespace of the identity constraint.

     *

     * Just short for <code>getParent().getTargetNamespace()</code>.

     */

    String getTargetNamespace();

    /**

     * Returns the type of the identity constraint.

     *

     * @return

     *      either {@link #KEY},{@link #KEYREF}, or {@link #UNIQUE}.

     */

    short getCategory();

    final short KEY = 0;

    final short KEYREF = 1;

    final short UNIQUE = 2;

    /**

     * Returns the selector XPath expression as string.

     *

     * @return

     *      never null.

     */

    XSXPath getSelector();

    /**

     * Returns the list of field XPaths.

     *

     * @return

     *      a non-empty read-only list of {@link String}s,

     *      each representing the XPath.

     */

    List<XSXPath> getFields();

    /**

     * If this is {@link #KEYREF}, returns the key {@link XSIdentityConstraint}

     * being referenced.

     *

     * @return

     *      always non-null (when {@link #getCategory()}=={@link #KEYREF}).

     * @throws IllegalStateException

     *      if {@link #getCategory()}!={@link #KEYREF}

     */

    XSIdentityConstraint getReferencedKey();

}