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/*
* Copyright (c) 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.
*
* 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.
*/
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.concurrent.atomic.AtomicInteger;
/* @test
* @bug 8027351 8148940
* @summary Basic test of the finalize method
*/
public class FinalizeOverride {
// finalizedCount is incremented when the finalize method is invoked
private static AtomicInteger finalizedCount = new AtomicInteger();
// finalizedSum and privateFinalizedInvoke are used to verify
// the right overrided finalize method is invoked
private static AtomicInteger finalizedSum = new AtomicInteger();
private static volatile boolean privateFinalizeInvoked = false;
public static void main(String[] argvs) throws IOException {
patchPrivateFinalize();
test(new Base(10), 10);
test(new Subclass(20), 0);
test(new SubSubclass(30), 30);
test(new PublicFinalize(40), 40*100+40);
test(new PrivateFinalize(50), 50);
test(new NoOverride(60), 60);
}
static void test(Object o, int expected) {
int count = finalizedCount.get();
int sum = finalizedSum.get();
privateFinalizeInvoked = false;
// force GC and finalization
o = null;
while (finalizedCount.get() != (count+1)) {
System.gc();
System.runFinalization();
// Running System.gc() and System.runFinalization() in a
// tight loop can trigger frequent safepointing that slows
// down the VM and, as a result, the test. (With the
// HotSpot VM, the effect of frequent safepointing is
// especially noticeable if the test is run with the
// -Xcomp flag.) Sleeping for a second after every
// garbage collection and finalization cycle gives the VM
// time to make progress.
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
System.out.println("Main thread interrupted, continuing execution.");
}
}
if (privateFinalizeInvoked) {
throw new RuntimeException("private finalize method invoked");
}
if (finalizedCount.get() != (count+1)) {
throw new RuntimeException("Unexpected count=" + finalizedCount +
" expected=" + (count+1));
}
if (finalizedSum.get() != (sum+expected)) {
throw new RuntimeException("Unexpected sum=" + finalizedSum +
" prev=" + sum + " value=" + expected);
}
}
static void patchPrivateFinalize() throws IOException {
// patch the private f_nal_ze method name to "finalize"
String testClasses = System.getProperty("test.classes", ".");
Path p = Paths.get(testClasses, "FinalizeOverride$PrivateFinalize.class");
byte[] bytes = Files.readAllBytes(p);
int len = "f_nal_ze".length();
for (int i=0; i < bytes.length-len; i++) {
if (bytes[i] == 'f' &&
bytes[i+1] == '_' &&
bytes[i+2] == 'n' &&
bytes[i+3] == 'a' &&
bytes[i+4] == 'l' &&
bytes[i+5] == '_' &&
bytes[i+6] == 'z' &&
bytes[i+7] == 'e')
{
// s%_%i%
bytes[i+1] = 'i';
bytes[i+5] = 'i';
break;
}
}
Files.write(p, bytes);
}
static class Base {
protected int value;
Base(int v) {
this.value = v;
}
int called() {
finalizedSum.addAndGet(value);
return value;
}
protected void finalize() {
System.out.println("Base.finalize() sum += " + called());
finalizedCount.incrementAndGet();
}
}
static class PublicFinalize extends Base {
PublicFinalize(int v) {
super(v);
}
public void finalize() {
finalizedSum.addAndGet(value * 100);
System.out.println("PublicFinalize.finalize() sum += " + called() +
"+"+value+"*100");
finalizedCount.incrementAndGet();
}
}
static class Subclass extends Base {
Subclass(int v) {
super(v);
}
protected void finalize() {
// no value added to sum
System.out.println("Subclass.finalize() sum += 0");
finalizedCount.incrementAndGet();
}
}
static class SubSubclass extends Subclass {
SubSubclass(int v) {
super(v);
}
protected final void finalize() {
finalizedSum.addAndGet(value);
System.out.println("SubSubclass.finalize() sum +=" +value);
finalizedCount.incrementAndGet();
}
}
static class PrivateFinalize extends Base {
PrivateFinalize(int v) {
super(v);
}
private void f_nal_ze() {
// finalization catches any exception
System.out.println("Error: private finalize invoked!!");
privateFinalizeInvoked = true;
finalizedCount.incrementAndGet();
}
}
static class NoOverride extends PrivateFinalize {
NoOverride(int v) {
super(v);
}
}
}
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