out.println(String.format("%18d",gdso.iscVaxInteger(dbstat, i, 2)));

// compile: javac -cp .;jaybird-full-2.2.4.jar FbGatherStatistics.java
// run:     java -cp .;jaybird-full-2.2.4.jar FbGatherStatistics 1>FbGatherStatistics.log 2>FbGatherStatistics.err
import static java.lang.System.*;
import java.text.*;
import org.firebirdsql.gds.*;
public final class FbGatherStatistics
{
  private static DateFormat df = new SimpleDateFormat("HH:mm:ss.SSS");
  //private static final String DB_URL="192.168.0.201/3252:empty25";
  private static final String DB_URL="192.168.0.220/3330:idx_test";
  private static final String DB_USER="sysdba";
  private static final String DB_PSWD="masterke";
  static public void main (String args[]) throws Exception
  {
    try {

      org.firebirdsql.gds.GDS gdso = org.firebirdsql.gds.GDSObjectFactory.createJavaGDSImpl();
      // Factory method to create a new IscDbHandle instance specific to the implementation of this interface.
      IscDbHandle dh =  gdso.createIscDbHandle();

      DatabaseParameterBuffer dpb = gdso.createDatabaseParameterBuffer();
      dpb.addArgument(DatabaseParameterBuffer.USER, DB_USER);
      dpb.addArgument(DatabaseParameterBuffer.PASSWORD, DB_PSWD);
      dpb.addArgument(DatabaseParameterBuffer.CONNECT_TIMEOUT, 2000);
      //out.println("dpb="+dpb); org.firebirdsql.gds.impl.wire.DatabaseParameterBufferImp@a956ac07

      out.println( df.format( System.currentTimeMillis() )+ " trying to attach. . .");
      gdso.iscAttachDatabase(DB_URL, dh, dpb);
      out.println( df.format( System.currentTimeMillis() )+" attached to "+DB_URL);

      byte[] dbstat;
      byte[] items = {  ISCConstants.isc_info_reads,
                        ISCConstants.isc_info_writes,
                        ISCConstants.isc_info_fetches,
                        ISCConstants.isc_info_marks,
                        ISCConstants.isc_info_end,
                    };
      
      while(true) {
        try {  
            out.println(df.format( System.currentTimeMillis() )+" trying to gather db statistics. . .");
            dbstat=gdso.iscDatabaseInfo(dh, items, 128);
            out.println(df.format( System.currentTimeMillis() )+" statistics gathered, dbstat[] length="+dbstat.length);
            //out.println(dbstat.length);
            int i=0;
            boolean f;
            while( dbstat[i]!=ISCConstants.isc_info_end) { 
                // API guide: A one-byte item return type. 
                // There are compile-time constants defined for all the item return
                // types in ibase.h (inf_pub.h ?)
                byte item=dbstat[i++];
                // API guide:  A two-byte number specifying the number of bytes that 
                // follow in the remainder of the cluster.          
                int len = gdso.iscVaxInteger(dbstat, i, 2);
                i+=2;
                f=false;
                switch (item){
                  case ISCConstants.isc_info_reads: 
                      out.print("\t\treads  :");
                      f=true;
                      break;
                  case ISCConstants.isc_info_writes:
                      out.print("\t\twrites :");
                      f=true;
                      break;

                  case ISCConstants.isc_info_fetches: 
                      out.print("\t\tfetches:");
                      f=true;
                      break;
                  case ISCConstants.isc_info_marks:
                      out.print("\t\tmarks  :");
                      f=true;
                      break;
                  default:
                      break;
                }
                if (f)
                  out.println(String.format("%18d",gdso.iscVaxInteger(dbstat, i, len )));
                i+=len;
            }
            Thread.sleep(5000);
        } catch (GDSException e)   {
            break;
        }
      }

      out.println (df.format( System.currentTimeMillis() )+" detaching from database. . .");
      gdso.iscDetachDatabase(dh);
      out.println (df.format( System.currentTimeMillis() )+" detached.");
    }
    catch (GDSException e) {
        out.println(df.format( System.currentTimeMillis() )+" EXCEPTION: SQLSTATE="+e.getSQLState()+", fb_error="+e.getFbErrorCode()+", msg="+e.getMessage());
    }
  }
}

19:14:38.021 trying to attach. . .
19:14:38.193 attached to 192.168.0.220/3330:idx_test
19:14:38.193 trying to gather db statistics. . .
19:14:38.193 statistics gathered, dbstat[] length=33
		reads  :               171
		writes :           2288335
		fetches:       -1927992252
		marks  :          65169859
19:14:43.193 trying to gather db statistics. . .
19:14:43.193 statistics gathered, dbstat[] length=33
		reads  :               171
		writes :           2288580
		fetches:       -1916455014
		marks  :          65176854
19:14:48.193 trying to gather db statistics. . .
19:14:48.193 statistics gathered, dbstat[] length=33
		reads  :               171
		writes :           2289151
		fetches:       -1904960438
		marks  :          65191330

24.11.1999  06:00            3 579 077 ApiGuide.pdf

21:36:40.037 trying to attach. . .
21:36:40.209 attached to 192.168.0.220/3330:idx_test
21:36:40.209 trying to gather db statistics. . .
21:36:40.209 statistics gathered, dbstat[] length=33
21:36:40.209            reads                    0; diff:                 -1
21:36:40.209            writes                   0; diff:                 -1
21:36:40.209            fetches                  0; diff:                 -1
21:36:40.209            marks                    0; diff:                 -1

21:36:45.209 trying to gather db statistics. . .
21:36:45.209 statistics gathered, dbstat[] length=33
21:36:45.209            reads                  225; diff:                  0
21:36:45.209            writes             3197215; diff:                790
21:36:45.209            fetches          552716269; diff:           11447955
21:36:45.209            marks             92552294; diff:              25592

21:36:50.209 trying to gather db statistics. . .
21:36:50.209 statistics gathered, dbstat[] length=33
21:36:50.209            reads                  225; diff:                  0
21:36:50.209            writes             3198005; diff:                174
21:36:50.209            fetches          564164224; diff:           11572423
21:36:50.209            marks             92577886; diff:               2950

21:36:55.209 trying to gather db statistics. . .
21:36:55.209 statistics gathered, dbstat[] length=33
21:36:55.209            reads                  225; diff:                  0
21:36:55.209            writes             3198179; diff:                623
21:36:55.209            fetches          575736647; diff:           11444395
21:36:55.209            marks             92580836; diff:              25262
. . .