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/*
* Copyright (c) 2013, 2017, 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.
*/
/*
* @test
* @bug 8009411
* @summary Test that a static method on an interface doesn't hide a default
* method with the same name and signature in a separate compilation
* scenario.
* @run main StaticInterfaceMethodInWayOfDefault
*/
import java.io.IOException;
import java.io.InputStream;
import java.lang.reflect.Method;
import java.util.concurrent.Callable;
public class StaticInterfaceMethodInWayOfDefault {
public interface A_v1 {
}
public interface A_v2 {
default void m() {
System.err.println("A.m() called");
}
}
public interface B extends A_v1 {
static void m() {
System.err.println("B.m() called");
}
}
public interface C_v1 extends B {
default void m() {
System.err.println("C.m() called");
}
}
public interface C_v2 extends B {
}
public static class TestTask implements Callable<String> {
@Override
public String call() {
try {
Method m = C_v1.class.getMethod("m", (Class<?>[])null);
return m.getDeclaringClass().getSimpleName();
} catch (NoSuchMethodException e) {
System.err.println("Couldn't find method");
return "ERROR";
}
}
}
public static void main(String[] args) throws Exception {
int errors = 0;
Callable<String> v1Task = new TestTask();
ClassLoader v2Loader = new V2ClassLoader(
StaticInterfaceMethodInWayOfDefault.class.getClassLoader());
Callable<String> v2Task = (Callable<String>) Class.forName(
TestTask.class.getName(),
true,
v2Loader).newInstance();
System.err.println("Running using _v1 classes:");
String res = v1Task.call();
if(!res.equals("C_v1")) {
System.err.println("Got wrong method, expecting C_v1, got: " + res);
errors++;
}
System.err.println("Running using _v2 classes:");
res = v2Task.call();
if(!res.equals("A_v1")) {
System.err.println("Got wrong method, expecting A_v1, got: " + res);
errors++;
}
if (errors != 0)
throw new RuntimeException("Errors found, check log for details");
}
/**
* A ClassLoader implementation that loads alternative implementations of
* classes. If class name ends with "_v1" it locates instead a class with
* name ending with "_v2" and loads that class instead.
*/
static class V2ClassLoader extends ClassLoader {
V2ClassLoader(ClassLoader parent) {
super(parent);
}
@Override
protected Class<?> loadClass(String name, boolean resolve)
throws ClassNotFoundException {
if (name.indexOf('.') < 0) { // root package is our class
synchronized (getClassLoadingLock(name)) {
// First, check if the class has already been loaded
Class<?> c = findLoadedClass(name);
if (c == null) {
c = findClass(name);
}
if (resolve) {
resolveClass(c);
}
return c;
}
}
else { // not our class
return super.loadClass(name, resolve);
}
}
@Override
protected Class<?> findClass(String name)
throws ClassNotFoundException {
// special class name -> replace it with alternative name
if (name.endsWith("_v1")) {
String altName = name.substring(0, name.length() - 3) + "_v2";
String altPath = altName.replace('.', '/').concat(".class");
try (InputStream is = getResourceAsStream(altPath)) {
if (is != null) {
byte[] bytes = is.readAllBytes();
// patch class bytes to contain original name
for (int i = 0; i < bytes.length - 2; i++) {
if (bytes[i] == '_' &&
bytes[i + 1] == 'v' &&
bytes[i + 2] == '2') {
bytes[i + 2] = '1';
}
}
return defineClass(name, bytes, 0, bytes.length);
}
else {
throw new ClassNotFoundException(name);
}
}
catch (IOException e) {
throw new ClassNotFoundException(name, e);
}
}
else { // not special class name -> just load the class
String path = name.replace('.', '/').concat(".class");
try (InputStream is = getResourceAsStream(path)) {
if (is != null) {
byte[] bytes = is.readAllBytes();
return defineClass(name, bytes, 0, bytes.length);
}
else {
throw new ClassNotFoundException(name);
}
}
catch (IOException e) {
throw new ClassNotFoundException(name, e);
}
}
}
}
}
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