java.lang.invoke: Add MethodHandleInfo.
This interface is being introduced ahead of MethodHandles.Lookup
to break a circular dependency.
test: MethodHandleInfoTest / make docs
bug: 30550796
Change-Id: I0f2b5f3dfcbfb3f4b3cc8a2ee495f928b4f9d159
diff --git a/luni/src/test/java/libcore/java/lang/invoke/MethodHandleInfoTest.java b/luni/src/test/java/libcore/java/lang/invoke/MethodHandleInfoTest.java
new file mode 100644
index 0000000..12b82b0
--- /dev/null
+++ b/luni/src/test/java/libcore/java/lang/invoke/MethodHandleInfoTest.java
@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License
+ */
+
+package libcore.java.lang.invoke;
+
+import junit.framework.TestCase;
+
+import java.lang.invoke.MethodHandleInfo;
+import java.lang.invoke.MethodType;
+
+import static java.lang.invoke.MethodHandleInfo.*;
+
+public class MethodHandleInfoTest extends TestCase {
+ public void test_toString() {
+ final MethodType type = MethodType.methodType(String.class, String.class);
+ String string = MethodHandleInfo.toString(REF_invokeVirtual, String.class, "concat", type);
+ assertEquals("invokeVirtual java.lang.String.concat:(String)String", string);
+
+ try {
+ MethodHandleInfo.toString(-1, String.class, "concat", type);
+ fail();
+ } catch (IllegalArgumentException expected) {
+ }
+
+ try {
+ MethodHandleInfo.toString(REF_invokeVirtual, String.class, null, type);
+ fail();
+ } catch (NullPointerException expected) {
+ }
+
+ try {
+ MethodHandleInfo.toString(REF_invokeVirtual, null, "concat", type);
+ fail();
+ } catch (NullPointerException expected) {
+ }
+
+ try {
+ MethodHandleInfo.toString(REF_invokeVirtual, String.class, "concat", null);
+ fail();
+ } catch (NullPointerException expected) {
+ }
+ }
+
+ public void test_referenceKindToString() {
+ assertEquals("getField", referenceKindToString(REF_getField));
+ assertEquals("getStatic", referenceKindToString(REF_getStatic));
+ assertEquals("putField", referenceKindToString(REF_putField));
+ assertEquals("putStatic", referenceKindToString(REF_putStatic));
+ assertEquals("invokeVirtual", referenceKindToString(REF_invokeVirtual));
+ assertEquals("invokeStatic", referenceKindToString(REF_invokeStatic));
+ assertEquals("invokeSpecial", referenceKindToString(REF_invokeSpecial));
+ assertEquals("newInvokeSpecial", referenceKindToString(REF_newInvokeSpecial));
+ assertEquals("invokeInterface", referenceKindToString(REF_invokeInterface));
+
+ try {
+ referenceKindToString(-1);
+ fail();
+ } catch (IllegalArgumentException expected) {
+ }
+
+ try {
+ referenceKindToString(256);
+ fail();
+ } catch (IllegalArgumentException expected) {
+ }
+ }
+}
diff --git a/ojluni/src/lambda/java/java/lang/invoke/MethodHandleInfo.java b/ojluni/src/lambda/java/java/lang/invoke/MethodHandleInfo.java
deleted file mode 100644
index 68a736c..0000000
--- a/ojluni/src/lambda/java/java/lang/invoke/MethodHandleInfo.java
+++ /dev/null
@@ -1,62 +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.invoke.MethodHandles.Lookup;
-import java.lang.reflect.Member;
-
-public
-interface MethodHandleInfo {
- public static final int REF_getField = 0;
- public static final int REF_getStatic = 0;
- public static final int REF_putField = 0;
- public static final int REF_putStatic = 0;
- public static final int REF_invokeVirtual = 0;
- public static final int REF_invokeStatic = 0;
- public static final int REF_invokeSpecial = 0;
- public static final int REF_newInvokeSpecial = 0;
- public static final int REF_invokeInterface = 0;
-
- public int getReferenceKind();
-
- public Class<?> getDeclaringClass();
-
- public String getName();
-
- public MethodType getMethodType();
-
- public <T extends Member> T reflectAs(Class<T> expected, Lookup lookup);
-
- public int getModifiers();
-
- public default boolean isVarArgs() { return false; }
-
- public static String referenceKindToString(int referenceKind) { return null; }
-
- public static String toString(int kind, Class<?> defc, String name, MethodType type) {
- return null;
- }
-}
diff --git a/ojluni/src/main/java/java/lang/invoke/MethodHandleInfo.java b/ojluni/src/main/java/java/lang/invoke/MethodHandleInfo.java
new file mode 100644
index 0000000..08ce6f0
--- /dev/null
+++ b/ojluni/src/main/java/java/lang/invoke/MethodHandleInfo.java
@@ -0,0 +1,321 @@
+/*
+ * 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 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 {@code Lookup#revealDirect Lookup.revealDirect}.
+ * <h1><a name="directmh"></a>Direct Method Handles</h1>
+ * A <em>direct method handle</em> 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 <em>underlying member</em>.
+ * Direct method handles may be obtained in any of these ways:
+ * <ul>
+ * <li>By executing an {@code ldc} instruction on a {@code CONSTANT_MethodHandle} constant.
+ * (See the Java Virtual Machine Specification, sections 4.4.8 and 5.4.3.)
+ * <li>By calling one of the <a href="MethodHandles.Lookup.html#lookups">Lookup Factory Methods</a>,
+ * such as {@code Lookup#findVirtual Lookup.findVirtual},
+ * to resolve a symbolic reference into a method handle.
+ * A symbolic reference consists of a class, name string, and type.
+ * <li>By calling the factory method {@code Lookup#unreflect Lookup.unreflect}
+ * or {@code Lookup#unreflectSpecial Lookup.unreflectSpecial}
+ * to convert a {@link Method} into a method handle.
+ * <li>By calling the factory method {@code Lookup#unreflectConstructor Lookup.unreflectConstructor}
+ * to convert a {@link Constructor} into a method handle.
+ * <li>By calling the factory method {@code Lookup#unreflectGetter Lookup.unreflectGetter}
+ * or {@code Lookup#unreflectSetter Lookup.unreflectSetter}
+ * to convert a {@link Field} into a method handle.
+ * </ul>
+ *
+ * <h1>Restrictions on Cracking</h1>
+ * 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.
+ * <p>
+ * If the underlying method is <a href="MethodHandles.Lookup.html#callsens">caller sensitive</a>,
+ * the direct method handle will have been "bound" to a particular caller class, the
+ * {@code 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}).
+ * <p>
+ * 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 {@code java.lang.invoke.MethodHandles#reflectAs} to override this limitation.
+ *
+ * <h1><a name="refkinds"></a>Reference kinds</h1>
+ * The <a href="MethodHandles.Lookup.html#lookups">Lookup Factory Methods</a>
+ * correspond to all major use cases for methods, constructors, and fields.
+ * These use cases may be distinguished using small integers as follows:
+ * <table border=1 cellpadding=5 summary="reference kinds">
+ * <tr><th>reference kind</th><th>descriptive name</th><th>scope</th><th>member</th><th>behavior</th></tr>
+ * <tr>
+ * <td>{@code 1}</td><td>{@code REF_getField}</td><td>{@code class}</td>
+ * <td>{@code FT f;}</td><td>{@code (T) this.f;}</td>
+ * </tr>
+ * <tr>
+ * <td>{@code 2}</td><td>{@code REF_getStatic}</td><td>{@code class} or {@code interface}</td>
+ * <td>{@code static}<br>{@code FT f;}</td><td>{@code (T) C.f;}</td>
+ * </tr>
+ * <tr>
+ * <td>{@code 3}</td><td>{@code REF_putField}</td><td>{@code class}</td>
+ * <td>{@code FT f;}</td><td>{@code this.f = x;}</td>
+ * </tr>
+ * <tr>
+ * <td>{@code 4}</td><td>{@code REF_putStatic}</td><td>{@code class}</td>
+ * <td>{@code static}<br>{@code FT f;}</td><td>{@code C.f = arg;}</td>
+ * </tr>
+ * <tr>
+ * <td>{@code 5}</td><td>{@code REF_invokeVirtual}</td><td>{@code class}</td>
+ * <td>{@code T m(A*);}</td><td>{@code (T) this.m(arg*);}</td>
+ * </tr>
+ * <tr>
+ * <td>{@code 6}</td><td>{@code REF_invokeStatic}</td><td>{@code class} or {@code interface}</td>
+ * <td>{@code static}<br>{@code T m(A*);}</td><td>{@code (T) C.m(arg*);}</td>
+ * </tr>
+ * <tr>
+ * <td>{@code 7}</td><td>{@code REF_invokeSpecial}</td><td>{@code class} or {@code interface}</td>
+ * <td>{@code T m(A*);}</td><td>{@code (T) super.m(arg*);}</td>
+ * </tr>
+ * <tr>
+ * <td>{@code 8}</td><td>{@code REF_newInvokeSpecial}</td><td>{@code class}</td>
+ * <td>{@code C(A*);}</td><td>{@code new C(arg*);}</td>
+ * </tr>
+ * <tr>
+ * <td>{@code 9}</td><td>{@code REF_invokeInterface}</td><td>{@code interface}</td>
+ * <td>{@code T m(A*);}</td><td>{@code (T) this.m(arg*);}</td>
+ * </tr>
+ * </table>
+ * @since 1.8
+ */
+// TODO(narayan) : Change @code back to @link once MethodHandles has been imported.
+public
+interface MethodHandleInfo {
+ /**
+ * A direct method handle reference kind,
+ * as defined in the <a href="MethodHandleInfo.html#refkinds">table above</a>.
+ */
+ // Android-changed: Inlined the values of these constants from MethodHandleNatives.Constants.
+ public static final int
+ REF_getField = 1,
+ REF_getStatic = 2,
+ REF_putField = 3,
+ REF_putStatic = 4,
+ REF_invokeVirtual = 5,
+ REF_invokeStatic = 6,
+ REF_invokeSpecial = 7,
+ REF_newInvokeSpecial = 8,
+ REF_invokeInterface = 9;
+
+ /**
+ * 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 <a href="MethodHandleInfo.html#refkinds">table above</a> 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}.
+ * <p>
+ * 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 <T> 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
+ */
+ // TODO(narayan): change the second argument back to MethodHandles.Lookup once that
+ // class has been introduced.
+ //
+ // public <T extends Member> T reflectAs(Class<T> expected, Lookup lookup);
+ //
+ // We need to temporarily keep the existing version because of a circular dependency between
+ // the two classes.
+ public <T extends Member> T reflectAs(Class<T> expected, Object 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:
+ * <pre>{@code
+ * getReferenceKind() >= REF_invokeVirtual && Modifier.isTransient(getModifiers())
+ * }</pre>
+ *
+ *
+ * @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 (refKindIsField(getReferenceKind()))
+ return false;
+ // not in the public API: Modifier.VARARGS
+ final int ACC_VARARGS = 0x00000080; // from JVMS 4.6 (Table 4.20)
+
+ // Android-changed: Removed assert() due to http://b/30862573
+ // assert(ACC_VARARGS == Modifier.TRANSIENT);
+ return Modifier.isTransient(getModifiers());
+ }
+
+ /**
+ * Returns the descriptive name of the given reference kind,
+ * as defined in the <a href="MethodHandleInfo.html#refkinds">table above</a>.
+ * 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
+ * <a href="MethodHandleInfo.html#refkinds">reference kind number</a>
+ */
+ public static String referenceKindToString(int referenceKind) {
+ if (!refKindIsValid(referenceKind))
+ throw newIllegalArgumentException("invalid reference kind", referenceKind);
+ return refKindName(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:
+ * <pre>{@code
+ * String.format("%s %s.%s:%s", referenceKindToString(kind), defc.getName(), name, type)
+ * }</pre>
+ *
+ * @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
+ * <a href="MethodHandleInfo.html#refkinds">reference kind number</a>
+ * @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);
+ }
+
+ // Android-changed: Inlined from MethodHandleNatives and changed to avoid references to
+ // REF_NONE and REF_LIMITED
+ static boolean refKindIsValid(int refKind) {
+ return (refKind >= REF_getField && refKind <= REF_invokeInterface);
+ }
+
+ // Android-changed: Inlined from MethodHandleNatives.
+ static boolean refKindIsField(int refKind) {
+ return (refKind <= REF_putStatic);
+ }
+
+ // Android-changed: Inlined from MethodHandleNatives and replaced 'byte' argument with
+ // 'int'.
+ static String refKindName(int refKind) {
+ switch (refKind) {
+ case REF_getField: return "getField";
+ case REF_getStatic: return "getStatic";
+ case REF_putField: return "putField";
+ case REF_putStatic: return "putStatic";
+ case REF_invokeVirtual: return "invokeVirtual";
+ case REF_invokeStatic: return "invokeStatic";
+ case REF_invokeSpecial: return "invokeSpecial";
+ case REF_newInvokeSpecial: return "newInvokeSpecial";
+ case REF_invokeInterface: return "invokeInterface";
+ default: return "REF_???";
+ }
+ }
+}
diff --git a/openjdk_java_files.mk b/openjdk_java_files.mk
index a8a66b2..12be9d2 100644
--- a/openjdk_java_files.mk
+++ b/openjdk_java_files.mk
@@ -1158,6 +1158,7 @@
ojluni/src/main/java/sun/misc/FloatingDecimal.java \
ojluni/src/main/java/java/lang/invoke/LambdaConversionException.java \
ojluni/src/main/java/java/lang/invoke/MethodHandle.java \
+ ojluni/src/main/java/java/lang/invoke/MethodHandleInfo.java \
ojluni/src/main/java/java/lang/invoke/MethodHandleStatics.java \
ojluni/src/main/java/java/lang/invoke/MethodType.java \
ojluni/src/main/java/java/lang/invoke/MethodTypeForm.java \
@@ -1619,7 +1620,6 @@
openjdk_lambda_stub_files := \
ojluni/src/lambda/java/java/lang/invoke/CallSite.java \
ojluni/src/lambda/java/java/lang/invoke/LambdaMetafactory.java \
- ojluni/src/lambda/java/java/lang/invoke/MethodHandleInfo.java \
ojluni/src/lambda/java/java/lang/invoke/MethodHandles.java \
ojluni/src/lambda/java/java/lang/invoke/SerializedLambda.java
openjdk_lambda_duplicate_stub_files := \