| /* |
| * Copyright (c) 2018, 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 |
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| * 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). |
| * |
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| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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| */ |
| |
| /* |
| * @test |
| * @bug 8046171 |
| * @summary Test method selection process for private/public nestmate invocation |
| * @compile TestMethodSelection.java |
| * @compile PB_A.jcod \ |
| * PC_B_A.jcod \ |
| * PC_B_PA.jcod \ |
| * PC_PB_A.jcod |
| * @run main/othervm TestMethodSelection |
| * @run main/othervm -Dsun.reflect.noInflation=true TestMethodSelection |
| */ |
| |
| // The first run will use NativeMethodAccessor and due to the limited number |
| // of calls we will not reach the inflation threshold. |
| // The second run disables inflation so we will use the GeneratedMethodAccessor |
| // instead. In this way both sets of Reflection classes are tested. |
| |
| /* |
| We are setting up a basic test structure as follows: |
| |
| class A { |
| ?? String m() { return "A::m"; } |
| } |
| class B extends A { |
| ?? String m() { return "B::m"; } |
| } |
| class C extends B { |
| ?? String m() { return "C::m"; } |
| } |
| |
| where the access modifier of m() is either public or private in all combinations. |
| The only cases of interest here are private and non-private, so we use public for |
| the non-private case. |
| |
| We then have a test function: |
| |
| void test(B target, String expected) { |
| check(target.m() == expected); |
| } |
| |
| where the call to target.m() is expressed as an invokevirtual B::m on target. We |
| then pass either a B instance or a C instance and check that the expected method |
| is invoked. In all cases the resolved method is B::m, so we are effectively |
| testing the method selection rules. We are not testing resolution here. |
| |
| The expected behaviour is as follows (where P means m() is private and - means |
| m() is public). |
| |
| Target A.m B.m C.m Result Reason |
| ------------------------------------------ |
| B P P n/a B.m [1] |
| B P - n/a B.m [2] |
| B - P n/a B.m [1] |
| B - - n/a B.m [2] |
| C P P P B.m [1] |
| C P P - B.m [1] |
| C P - P B.m [3] |
| C P - - C.m [2] |
| c - P P B.m [1] |
| C - P - B.m [1] |
| C - - P B.m [3] |
| C - - - C.m [2] |
| |
| [1] Resolved method is private => selected method == resolved method |
| [2] target-type.m() can override B.m => selected method == target-type.m() |
| [3] private C.m does not override resolved public method B.m, but |
| C has a superclass B, with B.m that (trivially) overrides resolved B.m |
| => selected method = B.m |
| |
| To allow us to do this in source code we encode the inheritance hierarchy in the |
| class name, and we use plain A (for example) when m() is public and PA when m() |
| is private. So class C_B_A defines a public m() and inherits public m() from |
| both B and A. While PC_PB_PA defines a private m() and also has private m() |
| defined in its superclasses PB and PA. |
| |
| For cases where the subclass makes a public method private we can't write this |
| directly in Java source code so we have to have jcod versions that change |
| the access modifier to private. This occurs for: |
| |
| - PC_B_A |
| - PB_A |
| - PC_B_PA |
| - PC_PB_A |
| |
| We test direct invocation from Java source, MethodHandle invocation and core |
| reflection invocation. For MH and reflection we look for the method in "B" to |
| maintain the same resolution process as in the direct case. |
| */ |
| |
| import java.lang.invoke.*; |
| import static java.lang.invoke.MethodHandles.*; |
| import static java.lang.invoke.MethodType.*; |
| import java.lang.reflect.InvocationTargetException; |
| |
| public class TestMethodSelection { |
| |
| static final MethodType M_T = MethodType.methodType(String.class); |
| |
| static class A { |
| public String m() { return "A::m"; } |
| } |
| static class PA { |
| private String m() { return "PA::m"; } |
| } |
| |
| static class B_A extends A { |
| public String m() { return "B_A::m"; } |
| } |
| static class B_PA extends PA { |
| public String m() { return "B_PA::m"; } |
| } |
| // jcod version will rewrite this to have private m() |
| static class PB_A extends A { |
| public String m() { return "PB_A::m"; } |
| } |
| static class PB_PA extends PA { |
| private String m() { return "PB_PA::m"; } |
| } |
| |
| static class C_B_A extends B_A { |
| public String m() { return "C_B_A::m"; } |
| } |
| // jcod version will rewrite this to have private m() |
| static class PC_B_A extends B_A { |
| public String m() { return "PC_B_A"; } |
| } |
| static class C_PB_A extends PB_A { |
| public String m() { return "C_PB_A::m"; } |
| } |
| // jcod version will rewrite this to have private m() |
| static class PC_PB_A extends PB_A { |
| public String m() { return "PC_PB_A"; } |
| } |
| static class C_B_PA extends B_PA { |
| public String m() { return "C_B_PA::m"; } |
| } |
| // jcod version will rewrite this to have private m() |
| static class PC_B_PA extends B_PA { |
| public String m() { return "PC_B_PA"; } |
| } |
| static class C_PB_PA extends PB_PA { |
| public String m() { return "C_PB_PA::m"; } |
| } |
| static class PC_PB_PA extends PB_PA { |
| private String m() { return "PC_PB_PA::m"; } |
| } |
| |
| // Need a test function for each of the "B" classes |
| |
| static void doInvoke(B_A target, String expected) throws Throwable { |
| // Direct |
| check(target.m(), expected); |
| // MethodHandle |
| MethodHandle mh = lookup().findVirtual(B_A.class, "m", M_T); |
| check((String)mh.invoke(target), expected); |
| // Reflection |
| check((String)B_A.class.getDeclaredMethod("m", new Class<?>[0]). |
| invoke(target, new Object[0]), expected); |
| } |
| static void doInvoke(B_PA target, String expected) throws Throwable { |
| // Direct |
| check(target.m(), expected); |
| // MethodHandle |
| MethodHandle mh = lookup().findVirtual(B_PA.class, "m", M_T); |
| check((String)mh.invoke(target), expected); |
| // Reflection |
| check((String)B_PA.class.getDeclaredMethod("m", new Class<?>[0]). |
| invoke(target, new Object[0]), expected); |
| } |
| static void doInvoke(PB_A target, String expected) throws Throwable { |
| // Direct |
| check(target.m(), expected); |
| // MethodHandle |
| MethodHandle mh = lookup().findVirtual(PB_A.class, "m", M_T); |
| check((String)mh.invoke(target), expected); |
| // Reflection |
| check((String)PB_A.class.getDeclaredMethod("m", new Class<?>[0]). |
| invoke(target, new Object[0]), expected); |
| } |
| static void doInvoke(PB_PA target, String expected) throws Throwable { |
| // Direct |
| check(target.m(), expected); |
| // MethodHandle |
| MethodHandle mh = lookup().findVirtual(PB_PA.class, "m", M_T); |
| check((String)mh.invoke(target), expected); |
| // Reflection |
| check((String)PB_PA.class.getDeclaredMethod("m", new Class<?>[0]). |
| invoke(target, new Object[0]), expected); |
| } |
| |
| static void check(String actual, String expected) { |
| if (!actual.equals(expected)) { |
| throw new Error("Selection error: expected " + expected + |
| " but got " + actual); |
| } |
| } |
| |
| public static void main(String[] args) throws Throwable { |
| // First pass a suitable "B" instance |
| doInvoke(new PB_PA(), "PB_PA::m"); |
| doInvoke(new B_PA(), "B_PA::m"); |
| doInvoke(new PB_A(), "PB_A::m"); |
| doInvoke(new B_A(), "B_A::m"); |
| // Now a "C" instance |
| doInvoke(new PC_PB_PA(), "PB_PA::m"); |
| doInvoke(new C_PB_PA(), "PB_PA::m"); |
| doInvoke(new PC_B_PA(), "B_PA::m"); |
| doInvoke(new C_B_PA(), "C_B_PA::m"); |
| doInvoke(new PC_PB_A(), "PB_A::m"); |
| doInvoke(new C_PB_A(), "PB_A::m"); |
| doInvoke(new PC_B_A(), "B_A::m"); |
| doInvoke(new C_B_A(), "C_B_A::m"); |
| } |
| } |
| |
| |
| |
| |