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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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,
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 *
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package java.lang.constant;

import java.lang.invoke.MethodHandle;
import java.lang.invoke.MethodHandles;
import java.lang.invoke.MethodType;
import java.util.Optional;

import static java.lang.constant.ConstantDescs.CR_MethodHandle;
import static java.util.Objects.requireNonNull;

/**
 * A <a href="package-summary.html#nominal">nominal descriptor</a> for a
 * {@link MethodHandle} constant that performs a {@link MethodHandle#asType(MethodType)}
 * adaptation on another {@link MethodHandle}.
 */
final class AsTypeMethodHandleDesc extends DynamicConstantDesc<MethodHandle>
        implements MethodHandleDesc {

    private final MethodHandleDesc underlying;
    private final MethodTypeDesc type;

    AsTypeMethodHandleDesc(MethodHandleDesc underlying, MethodTypeDesc type) {
        super(ConstantDescs.MHR_METHODHANDLE_ASTYPE, ConstantDescs.INVOKE_NAME, CR_MethodHandle,
              underlying, type);
        this.underlying = requireNonNull(underlying);
        this.type = requireNonNull(type);
    }

    @Override
    public MethodTypeDesc methodType() {
        return type;
    }

    @Override
    public MethodHandle resolveConstantDesc(MethodHandles.Lookup lookup)
            throws ReflectiveOperationException {
        MethodHandle handle = underlying.resolveConstantDesc(lookup);
        MethodType methodType = type.resolveConstantDesc(lookup);
        return handle.asType(methodType);
    }

    @Override
    public Optional<? extends ConstantDesc<ConstantDesc<MethodHandle>>> describeConstable() {
        DirectMethodHandleDesc bootstrap = ConstantDescs.MHR_METHODHANDLEDESC_ASTYPE;
        return Optional.of(DynamicConstantDesc.ofSymbolicExpression(bootstrap, underlying, type));
    }

    @Override
    public String toString() {
        return  String.format("%s.asType%s", underlying.toString(), type.displayDescriptor());
    }
}