@Override
            public void handle(IAsyncResult<String> result) {
                String propVal = result.getResult();
                String newVal = propVal + "+";
                sharedState.setProperty(namespace, propName, newVal, new IAsyncResultHandler<Void>() {
                    @Override
                    public void handle(IAsyncResult<Void> result) {
                        chain.doApply(request);
                    }
                });
            }
@see io.apiman.gateway.engine.policy.IPolicy#apply(io.apiman.gateway.engine.beans.ApiRequest, io.apiman.gateway.engine.policy.IPolicyContext, java.lang.Object, io.apiman.gateway.engine.policy.IPolicyChain)
gateway/test/src/test/java/io/apiman/gateway/test/policies/SimpleSharedStatePolicy.java