Description Jonathan Fomby 2018-07-15 15:44:25 EDT

Created attachment 274988 [details]
Standalone class demonstrating bug

I recently upgraded from Mars to Photon, and quickly ran into some unexpected problems with the new compiler.

Basically, Serializing and then deserializing a lambda declared via the normal arrow syntax works fine, but if the lambda is declared via the method reference then the subsequent deserialization fails.

This sounds similar to https://bugs.eclipse.org/bugs/show_bug.cgi?id=516620 but will fail when serializing/deserializing everything via eclipse.

// simulating a Wicket Model
public static class DummyModel<T> implements Serializable {
    private static final long serialVersionUID = 1L;
    private T object;

    public DummyModel(T t) {
        this.object = t;
    }

    public T getObject() {
        return object;
    }
}

// Shows the working and failing methods
@SuppressWarnings("unchecked")
public void runTest() throws IOException, ClassNotFoundException {
    final DummyModel<Boolean> booleanModel = new DummyModel<Boolean>(false);

    // Works with both eclipse and javac
    Object supp0 = (Serializable & Supplier<Boolean>) () -> booleanModel.getObject();
    System.out.println("result 0 - " + deserialize(serialize(supp0)).getClass());

    // Works with both javac but not eclipse
    Object supp1 = (Serializable & Supplier<Boolean>) booleanModel::getObject;
    System.out.println("result 1 - " + deserialize(serialize(supp1)).getClass());
}

// Error
Exception in thread "main" java.io.IOException: unexpected exception type
...
Caused by: java.lang.reflect.InvocationTargetException
....
Caused by: java.lang.IllegalArgumentException: Invalid lambda deserialization
	at SerializationBug.$deserializeLambda$(SerializationBug.java:1)
	... 16 more