Never mind, Eclipse bug (sigh)
“The truth is rarely pure and never simple.” ― Oscar Wilde
On Fri, May 23, 2014 at 4:38 PM, tetsuo <ronald.tet...@gmail.com> wrote:
> I'm using Java 8 lambdas with Wicket, and they make it really simple
> to have almost 100% type-safe code, without the verbosity of anonymous
> inner classes. With a few adapter classes and interfaces, it was
> relatively easy to integrate them.
>
> But I'm having some non-trivial problems with serialization. I think
> it's a bug in the compiler, but I'm curious if someone else has seen
> this:
>
>
> public class TestClass implements Serializable {
> String msg = "HEY!";
> SerializableRunnable runnable;
> public TestClass() {
> TestClass self = this;
> runnable = () -> self.say(); // uses a local copy of 'this'
> // runnable = () -> this.say(); // uses 'this' directly
> }
> public void say() {
> System.out.println(msg);
> }
> public static void main(String[] args) throws Exception {
> ByteArrayOutputStream buffer = new ByteArrayOutputStream();
> try (ObjectOutputStream out = new ObjectOutputStream(buffer)) {
> out.writeObject(new TestClass());
> }
> try (ObjectInputStream in = new ObjectInputStream(new
> ByteArrayInputStream(buffer.toByteArray()))) {
> TestClass s = (TestClass) in.readObject();
> s.say();
> }
> }
> }
> interface SerializableRunnable extends Runnable, Serializable {
> }
>
>
> The above code runs fine, but if I use the commented line to
> initialize the runnable (using 'this' directly instead of a local
> variable), the in.readObject() call throws an excetion
> ('java.lang.IllegalArgumentException: Invalid lambda
> deserialization'). The object is serialized, but can't be
> deserialized.
>
> That is, lambdas are correctly serialized when it only uses the local
> scope, but if it tries to use the enclosing class directly (methods or
> attributes), it fails. I mean, it compiles, it works, it can access
> them, but if serialized, it can't be deserialized.
>
> Obviously, it makes it very inconvenient to use with Wicket, which
> uses serialization extensively.
>
> I already submited a bug to Oracle. Do you agree that it looks like a bug?
