@Override
    public IReadWriteStream<ApiResponse> getResponseDataHandler(ApiResponse response,
            IPolicyContext context, Object policyConfiguration) {
        return null;
    }
@see io.apiman.gateway.engine.policy.IDataPolicy#getResponseDataHandler(io.apiman.gateway.engine.beans.ApiResponse, io.apiman.gateway.engine.policy.IPolicyContext, java.lang.Object)
gateway/test/src/test/java/io/apiman/gateway/test/policies/SimpleDataPolicy.java