Official reasons for “Software caused connection a

Question

Given this stack trace snippet

Caused by: java.net.SocketException: Software caused connection abort: socket write error
 at java.net.SocketOutputStream.socketWrite0(Native Method)

I tried to answer the following questions:

1. What code is throwing this exception? (JVM?/Tomcat?/My code?)
2. What causes this exception to be thrown?

Regarding #1:

Sun's JVM source doesn't contain this exact message, but I think the text Software caused connection abort: socket write error is from the native implementation of SocketOutputStream:

private native void socketWrite0(FileDescriptor fd, byte[] b, int off,
                 int len) throws IOException;

Regarding #2

My guess is that it is caused when the client has terminated the connection, before getting the full response (e.g. sent a request, but before getting the full response, it got closed / terminated / offline)

Questions:

1. Are the above assumptions correct (#1 and #2)?
2. Can this be diffrentiated from the situation: "could not write to the client, due to a network error on the server side"? or would that render the same error message?
3. And most important: Is there an official document (e.g from Sun) stating the above?

I need to have a proof that this stack trace is the socket client's "fault", and there is nothing that the server could have done to avoid it. (except catching the exception, or using a non Sun JVM SocketOutputStream, though both don't really avoid the fact the client has terminated)

Answer 1

For anyone using simple Client Server programms and getting this error, it is a problem of unclosed (or closed to early) Input or Output Streams.

Answer 2

In the situation explained below, client side will throw such an exception:

The server is asked to authenticate client certificate, but the client provides a certificate which Extended Key Usage doesn't support client auth, so the server doesn't accept the client's certificate, and then it closes the connection.

Answer 3

This error happened to me while testing my soap service with SoapUI client, basically I was trying to get a very big message (>500kb) and SoapUI closed the connection by timeout.

On SoapUI go to:

File-->Preferences--Socket Timeout(ms)

...and put a large value, such as 180000 (3 minutes), this won't be the perfect fix for your issue because the file is in fact to large, but at least you will have a response.

Answer 4

I was facing the same problem with wireMock while mocking the rest API calls. Earlier I was defining the server like this:

WireMockServer wireMockServer = null;

But it should be defined like as shown below:

@Rule 
public WireMockRule wireMockRule = new WireMockRule(8089);

Answer 5

Have you checked the Tomcat source code and the JVM source ? That may give you more help.

I think your general thinking is good. I would expect a ConnectException in the scenario that you couldn't connect. The above looks very like it's client-driven.

Answer 6

To prove which component fails I would monitor the TCP/IP communication using wireshark and look who is actaully closing the port, also timeouts could be relevant.