Annotation processor in project incorrectly yields "[Java] <generated type> cannot be resolved to a type"

I have access to a specific (large) project here which makes use of

@SupportedAnnotationTypes({"the.namespace.TheAnnotation"})
@SupportedSourceVersion(SourceVersion.RELEASE_10)

to create an annotation processor

public class TheAnnotationProcessor extends AbstractProcessor {

for an annotation the.namespace.TheAnnotation in that project

public @interface TheAnnotation {

which produces an interface (e.g. GeneratedInterfaceSpecificMapper, see below) with plenty of default. In the very same project, this annotation is also applied to some classes,

@TheAnnotation(Specific.class)
public class SpecificMapper implements GeneratedInterfaceSpecificMapper {  

Evidently, maven discovers the annotation, the annotation processor, runs code generation through the processor (files appear in generated-sources/annotations/...) and is able to also compile the source files that make use of the GeneratedInterfaceSpecificMapper.

The vscode plugin flags the type GeneratedInterfaceSpecificMapper as faulty, with "[Java] cannot be resolved to a type". This seems to indicate that the vscode plugin is not aware of the generated artefacts in generated-sources/annotations/...

I have had a look at https://www.baeldung.com/java-annotation-processing-builder to see whether this produces the error - alas, that setup there seems to be too clean / too simplistic to trigger the problem.

Environment

• Operating System: Linux Fedora 28
• JDK version: 10.0.2
• Visual Studio Code version: 1.28.2
• Java extension version: java-0.33.0-1252.vsix

Steps To Reproduce

<large project, will try to find time to reduce>

Current Result

• builds fine in maven
• red squiggles in IDE / syntax check failure

Expected Result

• builds fine in maven
• no red squiggles in IDE

Additional Informations

Not sure whether this related to the issues reported for Lombok - e.g #580 or #458

从 Java 扩展的注解处理路径以及报告中描述的 generated-sources/annotations/... 输出开始；使用所引用的注解处理器和 GeneratedInterfaceSpecificMapper 重现 Maven 与 IDE 之间的差异。需要一个精简项目或等效的复现，并且完成的标准是 Maven 仍能构建，而 IDE 不再将生成的类型报告为无法解析。