/*

 * Copyright (c) 2012, 2013, 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.

 */

package java.lang.invoke;

import java.security.*;

import java.lang.reflect.*;

import java.lang.invoke.MethodHandleNatives.Constants;

import java.lang.invoke.MethodHandles.Lookup;

import static java.lang.invoke.MethodHandleStatics.*;

/*

 * Auxiliary to MethodHandleInfo, wants to nest in MethodHandleInfo but must be non-public.

 */

/*non-public*/

    private final MemberName member;

    private final int referenceKind;

    InfoFromMemberName(Lookup lookup, MemberName member, byte referenceKind) {

        assert(member.isResolved() || member.isMethodHandleInvoke() || member.isVarHandleMethodInvoke());

        assert(member.referenceKindIsConsistentWith(referenceKind));

        this.member = member;

        this.referenceKind = referenceKind;

    }

    @Override

    public Class<?> getDeclaringClass() {

        return member.getDeclaringClass();

    }

    @Override

    public String getName() {

        return member.getName();

    }

    @Override

    public MethodType getMethodType() {

        return member.getMethodOrFieldType();

    }

    @Override

    public int getModifiers() {

        return member.getModifiers();

    }

    @Override

    public int getReferenceKind() {

        return referenceKind;

    }

    @Override

    public String toString() {

        return MethodHandleInfo.toString(getReferenceKind(), getDeclaringClass(), getName(), getMethodType());

    }

    @Override

    public <T extends Member> T reflectAs(Class<T> expected, Lookup lookup) {

        if ((member.isMethodHandleInvoke() || member.isVarHandleMethodInvoke())

            && !member.isVarargs()) {

            // This member is an instance of a signature-polymorphic method, which cannot be reflected

            // A method handle invoker can come in either of two forms:

            // A generic placeholder (present in the source code, and varargs)

            // and a signature-polymorphic instance (synthetic and not varargs).

            // For more information see comments on {@link MethodHandleNatives#linkMethod}.

            throw new IllegalArgumentException("cannot reflect signature polymorphic method");

        }

        Member mem = AccessController.doPrivileged(new PrivilegedAction<>() {

                public Member run() {

                    try {

                        return reflectUnchecked();

                    } catch (ReflectiveOperationException ex) {

                        throw new IllegalArgumentException(ex);

                    }

                }

            });

        try {

            Class<?> defc = getDeclaringClass();

            byte refKind = (byte) getReferenceKind();

            lookup.checkAccess(refKind, defc, convertToMemberName(refKind, mem));

        } catch (IllegalAccessException ex) {

            throw new IllegalArgumentException(ex);

        }

        return expected.cast(mem);

    }

    private Member reflectUnchecked() throws ReflectiveOperationException {

        byte refKind = (byte) getReferenceKind();

        Class<?> defc = getDeclaringClass();

        boolean isPublic = Modifier.isPublic(getModifiers());

        if (MethodHandleNatives.refKindIsMethod(refKind)) {

            if (isPublic)

                return defc.getMethod(getName(), getMethodType().parameterArray());

            else

                return defc.getDeclaredMethod(getName(), getMethodType().parameterArray());

        } else if (MethodHandleNatives.refKindIsConstructor(refKind)) {

            if (isPublic)

                return defc.getConstructor(getMethodType().parameterArray());

            else

                return defc.getDeclaredConstructor(getMethodType().parameterArray());

        } else if (MethodHandleNatives.refKindIsField(refKind)) {

            if (isPublic)

                return defc.getField(getName());

            else

                return defc.getDeclaredField(getName());

        } else {

            throw new IllegalArgumentException("referenceKind="+refKind);

        }

    }

    private static MemberName convertToMemberName(byte refKind, Member mem) throws IllegalAccessException {

        if (mem instanceof Method) {

            boolean wantSpecial = (refKind == REF_invokeSpecial);

            return new MemberName((Method) mem, wantSpecial);

        } else if (mem instanceof Constructor) {

            return new MemberName((Constructor) mem);

        } else if (mem instanceof Field) {

            boolean isSetter = (refKind == REF_putField || refKind == REF_putStatic);

            return new MemberName((Field) mem, isSetter);

        }

        throw new InternalError(mem.getClass().getName());

    }

}