code: private void getCompositeIdEmbeddables(EmbeddableType embeddable, List compositeEmbeddables, MetamodelImpl metaModel)
      {
          compositeEmbeddables.add(embeddable.getJavaType().getSimpleName());
  
          for (Object column : embeddable.getAttributes())
          {
  
              Attribute columnAttribute = (Attribute) column;
              Field f = (Field) columnAttribute.getJavaMember();
  
              if (columnAttribute.getJavaType().isAnnotationPresent(Embeddable.class))
              {
                  getCompositeIdEmbeddables(metaModel.embeddable(columnAttribute.getJavaType()), compositeEmbeddables,
                          metaModel);
              }
          }
      }
docs: Gets the composite id embeddables.
  
  @param embeddable
  the embeddable
  @param compositeEmbeddables
  the composite embeddables
  @param metaModel
  the meta model
  @return the composite id embeddables