exchange only can be changed in process method

if we want to change header of exchange.getIn(), we should put the change logic into processor or bean, not in predicate, looks like in predicate, the exhcange is only a copy of real one, so any change won't be effective.

 

exchange.getIn().removeHeader("subject");
 exchange.getIn().removeHeader("to"); 
<method bean="Perdicate" method="checkMethod" />
 <bean ref="Processor" method="processMethod"></bean>