.transform(xpath("/book/@title").stringResult())
.to("direct:groupByCategory")
.end();
from("direct:groupByCategory")
.aggregate(header("category"), new SetAggregationStrategy()).completionTimeout(500)
.to("mock:out")
.end();
from("direct:combined")
.split(xpath("/books/book"))
.setHeader("category", xpath("/book/@category").stringResult())
.transform(xpath("/book/@title").stringResult())
.aggregate(header("category"), new SetAggregationStrategy()).completionTimeout(500)
.to("mock:out")
.endParent()
.end();
}