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/*
* Copyright (c) 2020, 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.
*
* 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 p;
import java.lang.invoke.MethodHandle;
import java.lang.invoke.MethodHandles;
import java.lang.invoke.MethodHandles.Lookup;
import java.lang.invoke.MethodType;
import java.net.URL;
import java.net.URLClassLoader;
import java.nio.file.Paths;
import java.util.Arrays;
import static java.lang.invoke.MethodHandles.Lookup.*;
public class Main {
/*
* Each Test object loads q.EndPoint and q.T with a custom loader.
* These types are used to look up a method handle "EndPoint::test(T)".
*/
static class Test {
final ClassLoader loader;
final Class<?> target;
final Class<?> param;
Test(String name) throws Exception {
URL url = Paths.get(System.getProperty("test.classes"), "modules", "m2")
.toUri().toURL();
this.loader = new URLClassLoader(name, new URL[]{url}, null);
this.target = Class.forName("q.EndPoint", true, loader);
this.param = Class.forName("q.T", true, loader);
assertTrue(target != q.EndPoint.class);
assertTrue(param != q.T.class);
}
/*
*
*/
public void verifyAccess(Lookup... publicLookups) throws Throwable {
System.err.println(loader.getName() + ": verify access for " + Arrays.toString(publicLookups));
for (Lookup lookup : publicLookups) {
assertTrue((lookup.lookupModes() & UNCONDITIONAL) == UNCONDITIONAL);
assertTrue((lookup.lookupModes() & PUBLIC) == 0);
MethodHandle mh = lookup.findVirtual(target, "test", MethodType.methodType(void.class, param));
mh.invoke(target.newInstance(), param.newInstance());
checkTypeConsistency(mh);
}
}
}
/*
* Verify that publicLookup can teleport to:
* 1) q.EndPoint defined in m2
* 2) q.EndPoint defined by a custom loader CL1 in one unnamed module
* 3) q.EndPoint defined by a custom loader CL2 in another unnamed module
*
* All the resulting Lookup objects are public lookups and can find
* any public accessible member.
*/
public static void main(String... args) throws Throwable {
Test test1 = new Test("CL1");
Test test2 = new Test("CL2");
Lookup lookup1 = MethodHandles.publicLookup();
Lookup lookup2 = MethodHandles.publicLookup().in(test1.target);
Lookup lookup3 = MethodHandles.publicLookup().in(test2.target);
assertTrue(lookup2.lookupClass().getClassLoader() != lookup3.lookupClass().getClassLoader());
test1.verifyAccess(lookup1, lookup2, lookup3);
test2.verifyAccess(lookup1, lookup2, lookup3);
}
static void checkTypeConsistency(MethodHandle mh) throws Throwable {
try {
mh.invoke(new q.EndPoint(), new q.T());
throw new Error("expect fail to invoke due to type inconsistency");
} catch (ClassCastException e) {
assertTrue(e.getMessage().startsWith("Cannot cast q."));
}
}
static void assertTrue(boolean v) {
if (!v) {
throw new AssertionError("unexpected result");
}
}
}
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