1 /* 2 * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 package java.lang.constant; 26 27 import java.lang.invoke.MethodHandle; 28 import java.lang.invoke.MethodHandles; 29 import java.lang.invoke.MethodType; 30 import java.util.Optional; 31 32 import static java.lang.constant.ConstantDescs.CR_MethodHandle; 33 import static java.util.Objects.requireNonNull; 34 35 /** 36 * A <a href="package-summary.html#nominal">nominal descriptor</a> for a 37 * {@link MethodHandle} constant that performs a {@link MethodHandle#asType(MethodType)} 38 * adaptation on another {@link MethodHandle}. 39 */ 40 final class AsTypeMethodHandleDesc extends DynamicConstantDesc<MethodHandle> 41 implements MethodHandleDesc { 42 43 private final MethodHandleDesc underlying; 44 private final MethodTypeDesc type; 45 46 AsTypeMethodHandleDesc(MethodHandleDesc underlying, MethodTypeDesc type) { 47 super(ConstantDescs.MHR_METHODHANDLE_ASTYPE, ConstantDescs.INVOKE_NAME, CR_MethodHandle, 48 underlying, type); 49 this.underlying = requireNonNull(underlying); 50 this.type = requireNonNull(type); 51 } 52 53 @Override 54 public MethodTypeDesc methodType() { 55 return type; 56 } 57 58 @Override 59 public MethodHandle resolveConstantDesc(MethodHandles.Lookup lookup) 60 throws ReflectiveOperationException { 61 MethodHandle handle = underlying.resolveConstantDesc(lookup); 62 MethodType methodType = type.resolveConstantDesc(lookup); 63 return handle.asType(methodType); 64 } 65 66 @Override 67 public Optional<? extends ConstantDesc<ConstantDesc<MethodHandle>>> describeConstable() { 68 DirectMethodHandleDesc bootstrap = ConstantDescs.MHR_METHODHANDLEDESC_ASTYPE; 69 return Optional.of(DynamicConstantDesc.ofSymbolicExpression(bootstrap, underlying, type)); 70 } 71 72 @Override 73 public String toString() { 74 return String.format("%s.asType%s", underlying.toString(), type.displayDescriptor()); 75 } 76 }