Spring Integration server with Java DSL - spring-boot

Question

I am looking for an example of a Spring Integration 4.3.14 TCP server that responds to a message using the Java DSL not XML.
The 4.3.14 requirment is set by corporate policy which also avoids XML.
The end requirment is to receive a formated text payload form a PLC and respond with likewise. The PLC code is legacy and not at all well defined and simular payloads can have diferent formats.
The easy way to deal with the input payload is to treat it as a string and deal with it in Java code.
I have a basic recive working but cant work out how to send the reply, read a lot of examples and such but now think the mind is just confued so a simple working example would be ideal.
Many thanks

Answer 1

Here you go...
#SpringBootApplication
public class So50412811Application {
public static void main(String[] args) {
SpringApplication.run(So50412811Application.class, args).close();
}
#Bean
public TcpNetServerConnectionFactory cf() {
return new TcpNetServerConnectionFactory(1234);
}
#Bean
public TcpInboundGateway gateway() {
TcpInboundGateway gw = new TcpInboundGateway();
gw.setConnectionFactory(cf());
return gw;
}
#Bean
public IntegrationFlow flow() {
return IntegrationFlows.from(gateway())
.transform(Transformers.objectToString())
.<String, String>transform(String::toUpperCase)
.get();
}
// client
#Bean
public ApplicationRunner runner() {
return args -> {
Socket socket = SocketFactory.getDefault().createSocket("localhost", 1234);
socket.getOutputStream().write("foo\r\n".getBytes()); // default CRLF deserializer
InputStream is = socket.getInputStream();
int in = 0;
while (in != 0x0a) {
in = is.read();
System.out.print((char) in);
}
socket.close();
};
}
}