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Re: simple soclet communication between 2 PCs
yes - because my main java program operates on an hourly basis and it is NOT receiving a message from Computer 2
I probably have errors in the code on both sides at the moment but one main problem is that a message is NOT being sent from Computer 2 (Client Socket)
Re: simple soclet communication between 2 PCs
Be sure to close the open socket before trying to open another one.
Have you tested the code using the local host address? If the code works on one PC then the problem could be with firewalls and routers.
If you don't understand my answer, don't ignore it, ask a question.
Re: simple soclet communication between 2 PCs
My understanding is that if a message was successfully received by Computer 1, then the socket would be closed
Thus my prime problem is:- why does the code on Computer 2 (client) not send a message ?
Bob M
Re: simple soclet communication between 2 PCs
Does the code work on one PC using the local host address?
If you don't understand my answer, don't ignore it, ask a question.
Re: simple soclet communication between 2 PCs
Client error: (hourly)
SocketClient exception occurred: java.net.ConnectException: Connection refused: connect
Re: simple soclet communication between 2 PCs
Does the code test ok on the local PC?
If you don't understand my answer, don't ignore it, ask a question.
Re: simple soclet communication between 2 PCs
I do not understand you...........
Both PC's are local ?
Does the calling code on the Client side look OK ?
Re: simple soclet communication between 2 PCs
By local I mean that the server and client programs execute on the same (and only) PC using the localhost IP address: 127.0.0.1
Hard to say.Does the calling code on the Client side look OK ?
Make a small, complete program that compiles and can be executed for testing.
If you don't understand my answer, don't ignore it, ask a question.
Re: simple soclet communication between 2 PCs
In the calling code on the Client computer (No.2)
do I need to replace "localhost" with the IP address of Computer 1 ?
Bob M
p.s. have just replaced an ethernet cable - now both computers are on the same network
--- Update ---
Client - no error
Server error: (hourly)
SocketServer exception occurred: java.net.NullPointerException
Bob M
Re: simple soclet communication between 2 PCs
You need the full stack trace to see where that exception happened.java.net.NullPointerException
Yesdo I need to replace "localhost" with the IP address
Do the programs work with the localhost address when the server and client code are executed on the same PC?
If you don't understand my answer, don't ignore it, ask a question.
Re: simple soclet communication between 2 PCs
Here is the full stack trace
2019-06-18 23:00:03 at java.lang.Thread.run(Unknown Source)
2019-06-18 23:00:03 at com.dukascopy.api.impl.execution.f$a.run(L:926)
2019-06-18 23:00:03 at com.dukascopy.api.impl.execution.f$a.e(L:904)
2019-06-18 23:00:03 at java.util.concurrent.FutureTask.run(Unknown Source)
2019-06-18 23:00:03 at com.dukascopy.api.impl.execution.m.call(L:23)
2019-06-18 23:00:03 at com.dukascopy.api.impl.execution.m.call(L:63)
2019-06-18 23:00:03 at com.dukascopy.api.impl.execution.m.cu(L:85)
2019-06-18 23:00:03 at my_strategies.us_copiosus_GBPAUD_1010.onBar(us_cop iosus_GBPAUD_1010.java:471)
2019-06-18 23:00:03 at my_strategies.us_copiosus_GBPAUD_1010$SocketServer .start(us_copiosus_GBPAUD_1010.java:1720)
2019-06-18 23:00:03 java.lang.NullPointerException
2019-06-18 23:00:03 SocketServer exception occurred: java.lang.NullPointerException
2019-06-18 22:08:30 Strategy Started: GBP_AUD
I believe the following calling code from my main java program is incorrect
// initialise and start our thread
NewThread t = new NewThread();
t.start();
// setup socket connection on new background thread (to receive trading decision from Computer 2)
try {
SocketServer server = new SocketServer(9876);
server.start(); - stack trace points to this line as being in error - null exception
}
catch(Exception e) {
myConsole.getOut().println("SocketServer exception occured: " + e);
e.printStackTrace();
}
Re: simple soclet communication between 2 PCs
It is missing the first line(s) that gives the type of exception.the full stack trace
What variable on line 1720 has the null value? Backtrack in the code to see why.2019-06-18 23:00:03 at my_strategies.us_copiosus_GBPAUD_1010$SocketServer .start(us_copiosus_GBPAUD_1010.java:1720)
2019-06-18 23:00:03 java.lang.NullPointerException
Please answer this question:
Do the programs work with the localhost address when the server and client code are executed on the same PC?
Please wrap ALL posted code in code tags.I believe the following calling code
What do you think is incorrect?code from my main java program is incorrect
If you don't understand my answer, don't ignore it, ask a question.
Re: simple soclet communication between 2 PCs
Norm
The first line is NOT missing
there is no variable on line 1720
that line is
server.start();
Re: simple soclet communication between 2 PCs
server is a variable. It should be reference to a class with the method start().there is no variable on line 1720
that line is
server.start();
On all exception messages I've seen, the lines starting with at are not on the first line. The first line does not begin with at ...The first line is NOT missing
If you don't understand my answer, don't ignore it, ask a question.
Re: simple soclet communication between 2 PCs
the stack trace needs to be read from the bottom upwards - see the time stamps
Re: simple soclet communication between 2 PCs
Strange. I've never seen console output in reverse order. Usually the top is the oldest and the bottom the youngest.
If you don't understand my answer, don't ignore it, ask a question.
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