JDBC 4.J - Connection reset

Question

Hi,
I have problem with JDBC(4.1) cennection to MS SQL 2012. I have java application which is running in loop and contacting sql server. Java program works for few minutes(max 4hours) and then going to down with error message:
com.microsoft.sqlserver.jdbc.SQLServerException: Connection reset
        at com.microsoft.sqlserver.jdbc.SQLServerConnection.terminate(SQLServerC
onnection.java:1668)
        at com.microsoft.sqlserver.jdbc.SQLServerConnection.terminate(SQLServerC
onnection.java:1655)
        at com.microsoft.sqlserver.jdbc.TDSChannel.read(IOBuffer.java:1789)
        at com.microsoft.sqlserver.jdbc.TDSReader.readPacket(IOBuffer.java:4881)
        at com.microsoft.sqlserver.jdbc.TDSReader.nextPacket(IOBuffer.java:4791)
        at com.microsoft.sqlserver.jdbc.TDSReader.ensurePayload(IOBuffer.java:47
67)
        at com.microsoft.sqlserver.jdbc.TDSReader.readUnsignedByte(IOBuffer.java
:4970)
        at com.microsoft.sqlserver.jdbc.SQLServerResultSet.initializeNullCompres
sedColumns(SQLServerResultSet.java:711)
        at com.microsoft.sqlserver.jdbc.SQLServerResultSet.discardCurrentRow(SQL
ServerResultSet.java:1709)
        at com.microsoft.sqlserver.jdbc.SQLServerResultSet.fetchBufferNext(SQLSe
rverResultSet.java:1774)
        at com.microsoft.sqlserver.jdbc.SQLServerResultSet.next(SQLServerResultS
et.java:1034)
        at javaapplication1.JavaApplication1.main(JavaApplication1.java:79)
Anybody idea?
Thanks
Tom

Answer 1

Hi Eric,
thank you for the answer. I tried JDBC 4.0, 4.1 and our supplier works with JTDS. Both have the same result with connection reset exception. If I put query with few records(tens of record), it is work fine. But If I put query on table with 1000 - 1 000 000
recods, the loop is gooing to Exception (connection reset), sometimes it work few minutes sometimes it works for few hours.
Tom
code here:
public class JavaApplication1 {
    public static void main(String[] args) {
        String url = "jdbc:sqlserver://X.X.X.X\\ITSQL:1433;databaseName=Alvao;autoReconnect=true";
        Statement stmt = null;
        ResultSet result = null;
        String driver = "com.microsoft.sqlserver.jdbc.SQLServerDriver";
        String databaseUserName = "USER";
        String databasePassword = "PSWD";
        try {
           while(true){
            String col1, col2, col3;
            Class.forName(driver);
            conn = DriverManager.getConnection(url, databaseUserName, databasePassword);
            long startTime = System.currentTimeMillis();
            stmt = conn.createStatement();
            result = null;
            result = stmt.executeQuery("SELECT SYSDATETIME()");
            result.next();
            String serverTime = result.getString(1);
            System.out.println(serverTime);
            result = stmt.executeQuery("SELECT Convert(nvarchar(20), PK_USER_ID) +'_'+ Convert(nvarchar(20), PersonalId) +'_'+ Convert(nvarchar(20), Employment) as ret  FROM [Alvao].[nova_idm_export].[Person]
where PersonalId = '710804'");
            result.next();
            String result1 = result.getString(1);
            System.out.println(result1);
            result = stmt.executeQuery("SELECT count(*) celkem FROM [Alvao].[nova_idm_import].[tImportPerson]");
            result.next();
            String result2 = result.getString(1);
            System.out.println(result2);
            stmt.setQueryTimeout(30000);
// This table returns > 1 000 000 records. If I skip this query, the lopp newer crashes
            result = stmt.executeQuery("SELECT * FROM [Alvao].[dbo].[tblLog]");
            result.setFetchSize(10000);
            int counter = 0;
            while(result.next()){
             counter++;
            String result3 = Integer.toString(counter);
            System.out.println(result3);
            conn.close();
            long estimatedTime = System.currentTimeMillis() - startTime;
            System.out.println(estimatedTime);
            System.out.println("---------------");
            BufferedWriter bw = new BufferedWriter(new FileWriter("soubor.txt", true));
            bw.write(serverTime+" "+result1+" "+result2+" "+estimatedTime);
            bw.newLine();
            bw.flush();
Thread.sleep(2000);
        } catch (Exception e) {
            e.printStackTrace();
            try{
            BufferedWriter bw = new BufferedWriter(new FileWriter("souborChyb.txt", true));
            bw.write(e.getMessage());
            bw.newLine();
            bw.flush();
            }catch(IOException ex){