diff -r eca8e9c3ec3e -r cd50c1894ce5 rt/emul/compact/src/main/java/java/lang/invoke/MethodHandleInfo.java --- a/rt/emul/compact/src/main/java/java/lang/invoke/MethodHandleInfo.java Sun Aug 17 20:09:05 2014 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,284 +0,0 @@ -/* - * 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.lang.reflect.*; -import java.util.*; -import java.lang.invoke.MethodHandleNatives.Constants; -import java.lang.invoke.MethodHandles.Lookup; -import static java.lang.invoke.MethodHandleStatics.*; - -/** - * A symbolic reference obtained by cracking a direct method handle - * into its consitutent symbolic parts. - * To crack a direct method handle, call {@link Lookup#revealDirect Lookup.revealDirect}. - *

Direct Method Handles

- * A direct method handle represents a method, constructor, or field without - * any intervening argument bindings or other transformations. - * The method, constructor, or field referred to by a direct method handle is called - * its underlying member. - * Direct method handles may be obtained in any of these ways: - * - * - *

Restrictions on Cracking

- * Given a suitable {@code Lookup} object, it is possible to crack any direct method handle - * to recover a symbolic reference for the underlying method, constructor, or field. - * Cracking must be done via a {@code Lookup} object equivalent to that which created - * the target method handle, or which has enough access permissions to recreate - * an equivalent method handle. - *

- * If the underlying method is caller sensitive, - * the direct method handle will have been "bound" to a particular caller class, the - * {@linkplain java.lang.invoke.MethodHandles.Lookup#lookupClass() lookup class} - * of the lookup object used to create it. - * Cracking this method handle with a different lookup class will fail - * even if the underlying method is public (like {@code Class.forName}). - *

- * The requirement of lookup object matching provides a "fast fail" behavior - * for programs which may otherwise trust erroneous revelation of a method - * handle with symbolic information (or caller binding) from an unexpected scope. - * Use {@link java.lang.invoke.MethodHandles#reflectAs} to override this limitation. - * - *

Reference kinds

- * The Lookup Factory Methods - * correspond to all major use cases for methods, constructors, and fields. - * These use cases may be distinguished using small integers as follows: - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - *
reference kinddescriptive namescopememberbehavior
{@code 1}{@code REF_getField}{@code class}{@code FT f;}{@code (T) this.f;}
{@code 2}{@code REF_getStatic}{@code class} or {@code interface}{@code static}
{@code FT f;}		{@code (T) C.f;}
{@code 3}{@code REF_putField}{@code class}{@code FT f;}{@code this.f = x;}
{@code 4}{@code REF_putStatic}{@code class}{@code static}
{@code FT f;}		{@code C.f = arg;}
{@code 5}{@code REF_invokeVirtual}{@code class}{@code T m(A*);}{@code (T) this.m(arg*);}
{@code 6}{@code REF_invokeStatic}{@code class} or {@code interface}{@code static}
{@code T m(A*);}		{@code (T) C.m(arg*);}
{@code 7}{@code REF_invokeSpecial}{@code class} or {@code interface}{@code T m(A*);}{@code (T) super.m(arg*);}
{@code 8}{@code REF_newInvokeSpecial}{@code class}{@code C(A*);}{@code new C(arg*);}
{@code 9}{@code REF_invokeInterface}{@code interface}{@code T m(A*);}{@code (T) this.m(arg*);}
- * @since 1.8 - */ -public -interface MethodHandleInfo { - /** - * A direct method handle reference kind, - * as defined in the table above. - */ - public static final int - REF_getField = Constants.REF_getField, - REF_getStatic = Constants.REF_getStatic, - REF_putField = Constants.REF_putField, - REF_putStatic = Constants.REF_putStatic, - REF_invokeVirtual = Constants.REF_invokeVirtual, - REF_invokeStatic = Constants.REF_invokeStatic, - REF_invokeSpecial = Constants.REF_invokeSpecial, - REF_newInvokeSpecial = Constants.REF_newInvokeSpecial, - REF_invokeInterface = Constants.REF_invokeInterface; - - /** - * Returns the reference kind of the cracked method handle, which in turn - * determines whether the method handle's underlying member was a constructor, method, or field. - * See the table above for definitions. - * @return the integer code for the kind of reference used to access the underlying member - */ - public int getReferenceKind(); - - /** - * Returns the class in which the cracked method handle's underlying member was defined. - * @return the declaring class of the underlying member - */ - public Class getDeclaringClass(); - - /** - * Returns the name of the cracked method handle's underlying member. - * This is {@code "<init>"} if the underlying member was a constructor, - * else it is a simple method name or field name. - * @return the simple name of the underlying member - */ - public String getName(); - - /** - * Returns the nominal type of the cracked symbolic reference, expressed as a method type. - * If the reference is to a constructor, the return type will be {@code void}. - * If it is to a non-static method, the method type will not mention the {@code this} parameter. - * If it is to a field and the requested access is to read the field, - * the method type will have no parameters and return the field type. - * If it is to a field and the requested access is to write the field, - * the method type will have one parameter of the field type and return {@code void}. - *

- * Note that original direct method handle may include a leading {@code this} parameter, - * or (in the case of a constructor) will replace the {@code void} return type - * with the constructed class. - * The nominal type does not include any {@code this} parameter, - * and (in the case of a constructor) will return {@code void}. - * @return the type of the underlying member, expressed as a method type - */ - public MethodType getMethodType(); - - // Utility methods. - // NOTE: class/name/type and reference kind constitute a symbolic reference - // member and modifiers are an add-on, derived from Core Reflection (or the equivalent) - - /** - * Reflects the underlying member as a method, constructor, or field object. - * If the underlying member is public, it is reflected as if by - * {@code getMethod}, {@code getConstructor}, or {@code getField}. - * Otherwise, it is reflected as if by - * {@code getDeclaredMethod}, {@code getDeclaredConstructor}, or {@code getDeclaredField}. - * The underlying member must be accessible to the given lookup object. - * @param the desired type of the result, either {@link Member} or a subtype - * @param expected a class object representing the desired result type {@code T} - * @param lookup the lookup object that created this MethodHandleInfo, or one with equivalent access privileges - * @return a reference to the method, constructor, or field object - * @exception ClassCastException if the member is not of the expected type - * @exception NullPointerException if either argument is {@code null} - * @exception IllegalArgumentException if the underlying member is not accessible to the given lookup object - */ - public T reflectAs(Class expected, Lookup lookup); - - /** - * Returns the access modifiers of the underlying member. - * @return the Java language modifiers for underlying member, - * or -1 if the member cannot be accessed - * @see Modifier - * @see #reflectAs - */ - public int getModifiers(); - - /** - * Determines if the underlying member was a variable arity method or constructor. - * Such members are represented by method handles that are varargs collectors. - * @implSpec - * This produces a result equivalent to: - * 

{@code
-     *     getReferenceKind() >= REF_invokeVirtual && Modifier.isTransient(getModifiers())
-     * }
- * - * - * @return {@code true} if and only if the underlying member was declared with variable arity. - */ - // spelling derived from java.lang.reflect.Executable, not MethodHandle.isVarargsCollector - public default boolean isVarArgs() { - // fields are never varargs: - if (MethodHandleNatives.refKindIsField((byte) getReferenceKind())) - return false; - // not in the public API: Modifier.VARARGS - final int ACC_VARARGS = 0x00000080; // from JVMS 4.6 (Table 4.20) - assert(ACC_VARARGS == Modifier.TRANSIENT); - return Modifier.isTransient(getModifiers()); - } - - /** - * Returns the descriptive name of the given reference kind, - * as defined in the table above. - * The conventional prefix "REF_" is omitted. - * @param referenceKind an integer code for a kind of reference used to access a class member - * @return a mixed-case string such as {@code "getField"} - * @exception IllegalArgumentException if the argument is not a valid - * reference kind number - */ - public static String referenceKindToString(int referenceKind) { - if (!MethodHandleNatives.refKindIsValid(referenceKind)) - throw newIllegalArgumentException("invalid reference kind", referenceKind); - return MethodHandleNatives.refKindName((byte)referenceKind); - } - - /** - * Returns a string representation for a {@code MethodHandleInfo}, - * given the four parts of its symbolic reference. - * This is defined to be of the form {@code "RK C.N:MT"}, where {@code RK} is the - * {@linkplain #referenceKindToString reference kind string} for {@code kind}, - * {@code C} is the {@linkplain java.lang.Class#getName name} of {@code defc} - * {@code N} is the {@code name}, and - * {@code MT} is the {@code type}. - * These four values may be obtained from the - * {@linkplain #getReferenceKind reference kind}, - * {@linkplain #getDeclaringClass declaring class}, - * {@linkplain #getName member name}, - * and {@linkplain #getMethodType method type} - * of a {@code MethodHandleInfo} object. - * - * @implSpec - * This produces a result equivalent to: - * 
{@code
-     *     String.format("%s %s.%s:%s", referenceKindToString(kind), defc.getName(), name, type)
-     * }
- * - * @param kind the {@linkplain #getReferenceKind reference kind} part of the symbolic reference - * @param defc the {@linkplain #getDeclaringClass declaring class} part of the symbolic reference - * @param name the {@linkplain #getName member name} part of the symbolic reference - * @param type the {@linkplain #getMethodType method type} part of the symbolic reference - * @return a string of the form {@code "RK C.N:MT"} - * @exception IllegalArgumentException if the first argument is not a valid - * reference kind number - * @exception NullPointerException if any reference argument is {@code null} - */ - public static String toString(int kind, Class defc, String name, MethodType type) { - Objects.requireNonNull(name); Objects.requireNonNull(type); - return String.format("%s %s.%s:%s", referenceKindToString(kind), defc.getName(), name, type); - } -}