/*
 * Copyright (c) 2016, 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
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

/*
 * This file is available under and governed by the GNU General Public
 * License version 2 only, as published by the Free Software Foundation.
 * However, the following notice accompanied the original version of this
 * file, and Oracle licenses the original version of this file under the BSD
 * license:
 */
/*
   Copyright 2016 Attila Szegedi

   Redistribution and use in source and binary forms, with or without
   modification, are permitted provided that the following conditions are
   met:
   * Redistributions of source code must retain the above copyright
     notice, this list of conditions and the following disclaimer.
   * Redistributions in binary form must reproduce the above copyright
     notice, this list of conditions and the following disclaimer in the
     documentation and/or other materials provided with the distribution.
   * Neither the name of the copyright holder nor the names of
     contributors may be used to endorse or promote products derived from
     this software without specific prior written permission.

   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
   IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
   TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
   PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDER
   BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
   BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
   OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
   ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

package jdk.dynalink;

/**
 * An enumeration of standard namespaces defined by Dynalink.
 */
public enum StandardNamespace implements Namespace {
    /**
     * Standard namespace for properties of an object.
     */
    PROPERTY,
    /**
     * Standard namespace for elements of a collection object.
     */
    ELEMENT,
    /**
     * Standard namespace for methods of an object. The method objects retrieved
     * through a {@link StandardOperation#GET} on this namespace can be (and where
     * object semantics allows they should be) unbound, that is: not bound to the
     * object they were retrieved through. When they are used with
     * {@link StandardOperation#CALL} an explicit "this" receiver argument is always
     * passed to them. Of course bound methods can be returned if the object semantics
     * requires them and such methods are free to ignore the receiver passed in the
     * {@code CALL} operation or even raise an error when it is different from the one
     * the method is bound to, or exhibit any other behavior their semantics requires
     * in such case.
     */
    METHOD;

    /**
     * If the passed in operation is a {@link NamespaceOperation}, or a
     * {@link NamedOperation} wrapping a {@link NamespaceOperation}, then it
     * returns the first (if any) {@link StandardNamespace} in its namespace
     * list. If the passed operation is not a namespace operation (optionally
     * wrapped in a named operation), or if it doesn't have any standard
     * namespaces in it, returns {@code null}.
     * @param op the operation
     * @return the first standard namespace in the operation's namespace list
     */
    public static StandardNamespace findFirst(final Operation op) {
        for(final Namespace ns: NamespaceOperation.getNamespaces(NamedOperation.getBaseOperation(op))) {
            if (ns instanceof StandardNamespace) {
                return (StandardNamespace)ns;
            }
        }
        return null;
    }
}