Ignoring responses in ServiceActivator of spring integration TCP Server

Question

I know spring integration has TcpInboundGateway, TcpOutboundGateway and ByteArrayStxEtxSerializer to handle data coming through TCP port.

ByteArrayStxEtxSerializer works great if the TCP server needs to read all the data sent from the client and then processes it. (request and response model) I am using single-use=false so that multiple requests can be processed in the same connection.

For example if the client sends 0x02AAPL0x03 then Server can send the AAPL price.

My TCP Server is working if the client sends 0x02AAPL0x030x02GOOG0x03. It sends the price of AAPL and GOOG price.

If there is invalid ticker, TCP server should ignore it and give the price of the valid tickers.

When the client sends 0x02AAPL0x030x2INVALIDTICKER0x030x02GOOG0x03, My client receives the AAPL price and waits for ever and times out.

My TCP Server uses ServiceActivator and returns null for INVALIDTICKER.

I am wondering why the client does not receive the valid prices. is the socket outputStream blocked? is there any setting which allows to skip some responses from the ServiceActivator?

Please help.

we are using spring integration 4.2.6.RELEASE version and java 8.

Here is my spring configuration:

   <bean id="connectionSerializeDeserialize" class="org.springframework.integration.ip.tcp.serializer.ByteArrayStxEtxSerializer"/>

    <int-ip:tcp-inbound-gateway id="gatewayCrLf"
        connection-factory="crLfServer"
        request-channel="serverBytes2StringChannel"
        error-channel="errorChannel"
        reply-timeout="10000"/> <!-- reply-timeout works on inbound-gateway -->

    <int:channel id="toSA" />

    <int:service-activator input-channel="toSA"
        ref="myService"
        method="prepare"/>

    <int:object-to-string-transformer id="serverBytes2String"
        input-channel="serverBytes2StringChannel"
        output-channel="toSA"/>

    <int:transformer id="errorHandler"
        input-channel="errorChannel"
        expression="payload.failedMessage.payload + ':' + payload.cause.message"/>

Thank you

Gary Russell Gary Russell · Accepted Answer · 2016-11-05T14:25:18

<int-ip:tcp-inbound-gateway id="gatewayCrLf"
    connection-factory="crLfServer"
    request-channel="serverBytes2StringChannel"
    error-channel="errorChannel"
    reply-timeout="10000"/> <!-- reply-timeout works on inbound-gateway -->

Returning null ends the flow, but the gateway doesn't know that - it could be that the reply might come on a different thread - he cannot tell that he will never get a reply for this request.

Since you have set the reply timeout to 10 seconds, the gateway (socket) thread will wait for that time before being able to do any more work.

Given that your flow is simple, you can safely set the reply timeout to 0 because, when there is a reply, it will already be available to process.

Ignoring responses in ServiceActivator of spring integration TCP Server

1 Answers