Vaadin 7.5.4: CustomFieldSerializers not considered during compilation

Vaadin 6 / 7 / 8
1

We are facing a strange problem during compilation when we want to send a custom bean TestBean from server to client in Vaadin 7.5.4 using ClientRpc.

public class TestBean implements Serializable {

    private TestDto dto;

    public TestDto getDto() {
        return dto;
    }

    public void setDto(TestDto dto) {
        this.dto = dto;
    }
}

public class TestDto implements Serializable {

    private String message;

    public TestDto(String message) {
        this.message = message;
    }

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }

}

During compliation we get the following error:

[ERROR]

Rebind result ‘my.test.TestDto’ has no default (zero argument) constructors

Because TestDto does not have a default (zero argument) constructor, we have implemented a CustomFieldSerializer and placed it in the same package of TestDto. Unfortunately, our custom serializer seems not to be considered by the vaadin compiler.

public final class TestDto_CustomFieldSerializer extends CustomFieldSerializer<TestDto> {

    public static void deserialize(SerializationStreamReader streamReader, TestDto instance) {
        // No fields
    }

    public static TestDto instantiate(SerializationStreamReader streamReader) throws SerializationException {
        return new TestDto(streamReader.readString());
    }

    public static void serialize(SerializationStreamWriter streamWriter, TestDto instance) throws SerializationException {
        streamWriter.writeString(instance.getMessage());
    }

    @Override
    public void deserializeInstance(SerializationStreamReader streamReader, TestDto instance) throws SerializationException {
        deserialize(streamReader, instance);
    }

    @Override
    public boolean hasCustomInstantiateInstance() {
        return true;
    }

    @Override
    public TestDto instantiateInstance(SerializationStreamReader streamReader) throws SerializationException {
        return instantiate(streamReader);
    }

    @Override
    public void serializeInstance(SerializationStreamWriter streamWriter, TestDto instance) throws SerializationException {
        serialize(streamWriter, instance);
    }

}

We have also found out that all built-in CustomFieldSerializer are working fine, but compilation always fails, when we use custom implementations and place them in the corresponding packages. In a separate test case, we have tried to send a collection HashBasedTable of guava-gwt from client to server. This class is also missing a default (zero argument) constructor, but the CustomFieldSerializer implementation HashBasedTable_CustomFieldSerializer is provided in the same package. During compilation, we get the same error:

[ERROR]

Rebind result ‘com.google.common.collect.HashBasedTable’ has no default (zero argument) constructors.

Refering to the GWT documentation, this seems to be a proper solution, when classes are missing a default (zero argument) constructor:
http://www.gwtproject.org/doc/latest/DevGuideServerCommunication.html#DevGuideCustomSerialization

Has anybody an idea what we are making wrong?