/*

 * Copyright (c) 2009, 2015, 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.

 *

 * 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.

 */

package jdk.vm.ci.hotspot;

import java.lang.invoke.CallSite;

import java.util.Objects;

import jdk.vm.ci.meta.Assumptions;

import jdk.vm.ci.meta.JavaConstant;

import jdk.vm.ci.meta.ResolvedJavaType;

import jdk.vm.ci.meta.VMConstant;

/**

 * Represents a constant non-{@code null} object reference, within the compiler and across the

 * compiler/runtime interface.

 */

public interface HotSpotObjectConstant extends JavaConstant, HotSpotConstant, VMConstant {

    @Override

    JavaConstant compress();

    @Override

    JavaConstant uncompress();

    /**

     * Gets the resolved Java type of the object represented by this constant.

     */

    HotSpotResolvedObjectType getType();

    /**

     * Gets the {@linkplain System#identityHashCode(Object) identity} has code for the object

     * represented by this constant.

     */

    int getIdentityHashCode();

    /**

     * Gets the result of {@link CallSite#getTarget()} for the {@link CallSite} object represented

     * by this constant.

     *

     * @param assumptions used to register an assumption that the {@link CallSite}'s target does not

     *            change

     * @return {@code null} if this constant does not represent a {@link CallSite} object

     */

    JavaConstant getCallSiteTarget(Assumptions assumptions);

    /**

     * Determines if this constant represents an {@linkplain String#intern() interned} string.

     */

    boolean isInternedString();

    /**

     * Gets the object represented by this constant represents if it is of a given type.

     *

     * @param type the expected type of the object represented by this constant. If the object is

     *            required to be of this type, then wrap the call to this method in

     *            {@link Objects#requireNonNull(Object)}.

     * @return the object value represented by this constant if it is an

     *         {@link ResolvedJavaType#isInstance(JavaConstant) instance of} {@code type} otherwise

     *         {@code null}

     */

    <T> T asObject(Class<T> type);

    /**

     * Gets the object represented by this constant represents if it is of a given type.

     *

     * @param type the expected type of the object represented by this constant. If the object is

     *            required to be of this type, then wrap the call to this method in

     *            {@link Objects#requireNonNull(Object)}.

     * @return the object value represented by this constant if it is an

     *         {@link ResolvedJavaType#isInstance(JavaConstant) instance of} {@code type} otherwise

     *         {@code null}

     */

    Object asObject(ResolvedJavaType type);

    @Override

    String toValueString();

}