SocketException in Java

In this post we will look into the details of 2 kinds of SocketException in Java
1) java.net.SocketException: Connection reset and
2) java.net.SocketException: Connection reset by peer: socket write error

1) java.net.SocketException: Connection reset

Occurs when :
While reading from the socket(inputstream)

Occurs where:
Server side or Client side

Reason:
If program(server/client) tries to read data from (client/server) using sockets InputStream and the other side(client/server) has gone down unexpectedly i.e crashed without closing its sockets or OutputStream.

However:
Note if the other(client/server) side closes its socket or related OutputStream (belonging to socket),this exception does not occur at the program(server/client) side.Closing the socket closes all the related output and input streams.

Summary:
If program tries to read from a socket input stream and the other side has gone down(crashed),or thread completes its run without closing the outputstream or socket.

Stack Trace:
java.net.SocketException: Connection reset
at java.net.SocketInputStream.read(SocketInputStream.java:168)
at java.net.SocketInputStream.read(SocketInputStream.java:182)
at java.io.FilterInputStream.read(FilterInputStream.java:66)
at SocketServerDemo.main(SocketServerDemo.java:27)
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2) java.net.SocketException: Connection reset by peer: socket write error

Occurs when :
While writing to the socket(outputstream)

Occurs where:
Server side or Client side

Reason:
If program(server/client) tries to write data to (client/server) using sockets OutputStream and the other side(client/server) has gone down unexpectedly i.e crashed without closing its sockets or InutputStream.

However:
Note if the other(client/server) side closes its socket or related InputStream (belonging to socket), this exception does not occur at the program(server/client) side.Closing the socket in turn closes all the related output and input streams.

Summary:
If program tries to write to the socket's output stream and the other side has gone down(crashed),or thread completes its run without closing the inputstream or socket.

Stack Trace:
java.net.SocketException: Connection reset by peer: socket write error
at java.net.SocketOutputStream.socketWrite0(Native Method)
at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java:92)
at java.net.SocketOutputStream.write(SocketOutputStream.java:115)
at java.io.DataOutputStream.write(DataOutputStream.java:71)
at ConnectionResetServerDemo_1.main(ConnectionResetServerDemo_1.java:15)
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How to convert Exception Stack Trace to String in Java ?

Below code snippet shows how to convert a Exception Stack Trace to String object in Java

public static String convertExStackTraceToString(Exception ex)
{
StringWriter sw = new StringWriter();
PrintWriter pw = new PrintWriter(sw);
ex.printStackTrace(pw);
sw.flush();
String strStackTrace = sw.toString();
try
{
sw.close();
pw.close();
}catch (IOException ex1)
{
ex1.printStackTrace();
}
return strStackTrace;
}