java.lang.IllegalArgumentException: couldn't construct type reference for type null

[BAVhel]

package test

import de.itemis.xtend.auto.gwt.OverlayTypeByExample

@OverlayTypeByExample('
{
    "AppConfig": {
        "Service": {
            "serviceUrl": "http://localhost:8080/test"
        }
    }
}
')
class JsonTest {
}

throw errors:
Description Resource Path Location Type
Error during annotation processing:
java.lang.IllegalArgumentException: couldn't construct type reference for type null
at org.eclipse.xtend.core.macro.declaration.TypeReferenceProviderImpl.newTypeReference(TypeReferenceProviderImpl.java:261)
at org.eclipse.xtend.core.macro.TransformationContextImpl.newTypeReference(TransformationContextImpl.java:204)
at de.itemis.xtend.auto.gwt.OverlayTypeByExampleProcessor$Util.getJavaType(OverlayTypeByExampleProcessor.java:157)
at de.itemis.xtend.auto.gwt.OverlayTypeByExampleProcessor$Util$2.apply(OverlayTypeByExampleProcessor.java:91)
at de.itemis.xtend.auto.gwt.OverlayTypeByExampleProcessor$Util$2.apply(OverlayTypeByExampleProcessor.java:85)
at org.eclipse.xtend.core.macro.declaration.JvmTypeDeclarationImpl.addMethod(JvmTypeDeclarationImpl.java:158)
at de.itemis.xtend.auto.gwt.OverlayTypeByExampleProcessor$Util.doTransform(OverlayTypeByExampleProcessor.java:95)
at de.itemis.xtend.auto.gwt.OverlayTypeByExampleProcessor$Util$3.apply(OverlayTypeByExampleProcessor.java:112)
at de.itemis.xtend.auto.gwt.OverlayTypeByExampleProcessor$Util$3.apply(OverlayTypeByExampleProcessor.java:100)
at de.itemis.xtend.auto.gwt.StaticUtils.processObject(StaticUtils.java:47)
at de.itemis.xtend.auto.gwt.OverlayTypeByExampleProcessor$Util.doTransform(OverlayTypeByExampleProcessor.java:116)
at de.itemis.xtend.auto.gwt.OverlayTypeByExampleProcessor.doTransform(OverlayTypeByExampleProcessor.java:283)
at org.eclipse.xtend.lib.macro.AbstractClassProcessor.doTransform(AbstractClassProcessor.java:42)
JsonTest.xtend /test/src/test line: 5 /test/src/test/JsonTest.xtend Xtend Problem

The package test.JsonTest.AppConfig collides with a type Service.java /test/target/generated-sources/xtend/test/JsonTest/AppConfig line 1 Java Problem

in generated-sources:

package test;

import com.google.gwt.core.client.JavaScriptObject;
import de.itemis.xtend.auto.gwt.OverlayTypeByExample;

/* @OverlayTypeByExample("\r\n{\r\n    \"AppConfig\": {\r\n        \"Service\": {\r\n            \"serviceUrl\": \"http://localhost:8080/test\"\r\n        }\r\n    }\r\n}\r\n")
 */@SuppressWarnings("all")
public class JsonTest extends JavaScriptObject {
  public static class AppConfig extends JavaScriptObject {
    protected AppConfig() {

    }

    public final native void getService() /*-{ return this.Service; }-*/;
  }

  protected JsonTest() {

  }

  public final native JsonTest.AppConfig getAppConfig() /*-{ return this.AppConfig; }-*/;
}

why public final native void getService() ?

Also if enabled Build Automatically project rebuilds constantly - probably it's different issue

[BAVhel]

The same error with xtend 2.8 but project doesn't rebuilds constantly as with xtend 2.7