[adding lambda-dev]
Here's another refinement to the test case, which shows that a serial clone
of Collections.reverseOrder in lambda8 creates a new instance of a new
class with the opposite order (which I can't explain):
When run against latest lambda-b76, it gives this output:
x=java.util.Collections$ReverseComparator@3710b205
y=java.util.Collections$ReverseComparator2@e9b8b810
x: 1 -1
y: -1 1
import java.util.*;
import java.io.*;
public class ReverseOrder {
public static void main(String[] args) throws Throwable {
Comparator x = Collections.reverseOrder();
Comparator y = serialClone(x);
System.out.printf("x=%s%n", x);
System.out.printf("y=%s%n", y);
System.out.printf("x: %d %d%n", x.compare(0,1), x.compare(1,0));
System.out.printf("y: %d %d%n", y.compare(0,1), y.compare(1,0));
}
static byte[] serialBytes(Object o) {
try {
ByteArrayOutputStream bos = new ByteArrayOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(bos);
oos.writeObject(o);
oos.flush();
oos.close();
return bos.toByteArray();
} catch (Throwable t) {
throw new Error(t);
}
}
@SuppressWarnings("unchecked")
static <T> T serialClone(T o) {
try {
ObjectInputStream ois = new ObjectInputStream
(new ByteArrayInputStream(serialBytes(o)));
T clone = (T) ois.readObject();
return clone;
} catch (Throwable t) {
throw new Error(t);
}
}
}
On Sat, Feb 9, 2013 at 3:31 PM, Martin Buchholz <marti...@google.com> wrote:
>
>
> On Sat, Feb 9, 2013 at 3:09 PM, Martin Buchholz <marti...@google.com>wrote:
>
>> It looks to me like Collections.reverseOrder no longer deserializes to
>> the same object. It also looks like the definition for that in
>> Collections.java hasn't changed recently. So I suspect that there has been
>> some serious incompatible change to deserialization itself.
>> (It's another matter whether that could break TreeSet).
>> (I have long lobbied for more cross-jdk testing focused on seriallization)
>>
>> The program below demonstrates the different behavior between jdk7 and
>> jdk8:
>>
>>
> Oops - correction - this is not a difference between jdk7 and jdk8, but
> between jdk8 and lambda8, More specifically, lambda-8-b74 fails,
> while jdk8-b74 succeeds. Have lambdadukes messed with serialization?
>
>
>
>> import java.util.*;
>> import java.io.*;
>>
>> public class ReverseOrder {
>> public static void main(String[] args) throws Throwable {
>> Comparator c = Collections.reverseOrder();
>> if (c != serialClone(c))
>> throw new Error(String.format("c=%s clone=%s",
>> c, serialClone(c)));
>> }
>>
>> static byte[] serialBytes(Object o) {
>> try {
>> ByteArrayOutputStream bos = new ByteArrayOutputStream();
>> ObjectOutputStream oos = new ObjectOutputStream(bos);
>> oos.writeObject(o);
>> oos.flush();
>> oos.close();
>> return bos.toByteArray();
>> } catch (Throwable t) {
>> throw new Error(t);
>> }
>> }
>>
>> @SuppressWarnings("unchecked")
>> static <T> T serialClone(T o) {
>> try {
>> ObjectInputStream ois = new ObjectInputStream
>> (new ByteArrayInputStream(serialBytes(o)));
>> T clone = (T) ois.readObject();
>> return clone;
>> } catch (Throwable t) {
>> throw new Error(t);
>> }
>> }
>> }
>>
>>
>> On Fri, Feb 8, 2013 at 3:16 PM, Mike Duigou <mike.dui...@oracle.com>wrote:
>>
>>> Thank you for catching this Doug. I missed your original post on this
>>> topic during my Christmas vacation. (
>>> http://mail.openjdk.java.net/pipermail/core-libs-dev/2012-December/013127.htmlfor
>>> those following along at home)
>>>
>>> I will definitely hold off and follow up on the potentially bad patch to
>>> Java 8. I have created an issue to resolve the test breakage, JDK-8007889
>>>
>>> Mike
>>>
>>> On Feb 8 2013, at 11:43 , Doug Lea wrote:
>>>
>>> > On 02/08/13 14:33, Mike Duigou wrote:
>>> >> Hello all;
>>> >>
>>> >> I would like to backport this change from Java 8. It has been baking
>>> in JDK8 for about two months with no problems.
>>> >>
>>> >
>>> > I think it may have problems.
>>> > As I mentioned in a post a few months ago, it seems
>>> > to be responsible for breakage in a TCK/JCK test;
>>> > One derived from a jsr166 tck test at
>>> >
>>> http://gee.cs.oswego.edu/cgi-bin/viewcvs.cgi/jsr166/src/test/tck/TreeSubSetTest.java?view=log
>>> >
>>> > You need the file for context, but it looks like:
>>> >
>>> > public void testDescendingSerialization() throws Exception {
>>> > NavigableSet x = dset5();
>>> > NavigableSet y = serialClone(x);
>>> >
>>> > assertTrue(x != y);
>>> > assertEquals(x.size(), y.size());
>>> > assertEquals(x.toString(), y.toString());
>>> > assertEquals(x, y);
>>> > assertEquals(y, x);
>>> > while (!x.isEmpty()) {
>>> > assertFalse(y.isEmpty());
>>> > assertEquals(x.pollFirst(), y.pollFirst());
>>> > }
>>> > assertTrue(y.isEmpty());
>>> > }
>>> >
>>> >
>>> >> http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7175464
>>> >>
>>> >> http://hg.openjdk.java.net/jdk8/jdk8/jdk/rev/bf6ceb6b8f80
>>> >>
>>> >> The change was previously reviewed by Alan Bateman, Paul Sandoz and
>>> David Holmes before going in to Java 8.
>>> >>
>>> >> Mike
>>> >>
>>> >
>>>
>>>
>>
>
