ResultSet.next() and resultset.islast() problem

I have query which returns 10 records. I run the using preparedStatement. When i use the while(resultSet.next()), the loop runs untill 10 records and after that when it come to the while check it hangs.
Sample code
pstmt= conn.prepareStatement(sql,ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_UPDATABLE);
rs = pstmt.executeQuery();
while (rsAccessNoEq.next()) {...
Then i added the code in the while loop
if(rs.isLast()){
return;
For the first iteration itself the theisLast() is true and it terminates from the loop.
Please help me

public class ISP {
     private GFA gestorFic = null;
     private GCA gestorCad = null;
     private GBDAgestor = null;
     private String path = null;
     ServiceProcessVO javaIntra = null;
     ServiceProcessVO javaIntra1 = null;
     ServiceProcessVO javaIntra2 = null;
     ServiceProcessVO javaIntra3 = null;
     ArrayList dataList = null;
     List dataFile = null;
     ArrayList dataList1 = null;
     ArrayList dataList2 = null;
     ArrayList dataList3 = null;
     public final void iP() throws SQLException,
     MCEA {
     ResultSet rsIntraHq = null;
          Connection connIntraHq = null;
          PreparedStatement pstmtIntraHq = null;
          ResultSet rsIntraFlow = null;
          Connection connIntraFlow = null;
          PreparedStatement pstmtIntraFlow = null;
          ResultSet rsEqNoAccess = null;
          Connection connEqNoAccess = null;
          PreparedStatement pstmtEqNoAccess = null;
          ResultSet rsAccessNoEq = null;
          Connection connAccessNoEq = null;
          PreparedStatement pstmtAccessNoEq = null;
          ResultSet rsFlowHqAccess = null;
          Connection connFlowHqAccess = null;
          PreparedStatement pstmtFlowHqAccess = null;
          dataList = new ArrayList();
          dataFile = new ArrayList();
          System.out.println("At the begining :"+now() );
          dataFile = gestorFic.leerArchivo(path, file);
          System.out.println("After first step :"+now() );
          int size1 = dataFile.size();
          try {
               connAccessNoEq = gestor.getConnection();
               javaIntra = new ServiceProcessVO();
               pstmtAccessNoEq = connAccessNoEq
               .prepareStatement(ConsultasAssets.INTRA_ACCESS_NOEQ);
                         //ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_UPDATABLE);
               pstmtAccessNoEq.setString(1, oti);
               pstmtAccessNoEq.setString(2, oti);
               pstmtAccessNoEq.setString(3, oti);
               rsAccessNoEq = pstmtAccessNoEq.executeQuery();
               //int k = rsAccessNoEq.TYPE_SCROLL_SENSITIVE;
               int i = 0;
               //rsAccessNoEq.last();
               while (rsAccessNoEq.next()) {
                    i++; System.out.println("Begin of loop:"+i);
                    javaIntra = populatedata(rsAccessNoEq, true);
                    dataList.add(javaIntra);
                    // Flow Hq Access
                    try {
                         connFlowHqAccess = gestor.getConnection();
                         javaIntra1 = new ServiceProcessVO();
                         pstmtFlowHqAccess = connFlowHqAccess
                         .prepareStatement(ConsultasAssets.HQ_ACCESS);
                         pstmtFlowHqAccess.setString(1, javaIntra
                                   .getCTASOCIACION().trim());
                         pstmtFlowHqAccess.setString(2, rsAccessNoEq.getString(1)
                                   .trim());
                         pstmtFlowHqAccess.setString(3, rsAccessNoEq.getString(3)
                                   .trim());
                         pstmtFlowHqAccess.setString(4,oti);
                         pstmtFlowHqAccess.setString(5,oti);
                         pstmtFlowHqAccess.setString(6,oti);
                         rsFlowHqAccess = pstmtFlowHqAccess.executeQuery();
                         while (rsFlowHqAccess.next()) {
                              javaIntra1 = populatedata(rsFlowHqAccess, false);
                              dataList.add(javaIntra1);
//                         if(rsAccessNoEq.isAfterLast()){
//                              return;
                    } catch (SQLException se) {
                         MCLA.logFatel(ClassNameAssets
                                   .getQualifiedClassName()
                                   + ": "
                                   + ClassNameAssets.getLineNumber()
                                   + ": "
                                   + "Error Occurred in HQ_ACCESS: "
                                   + se.getMessage());
                         throw new MigracionCommonExceptionAssets(se.getMessage());
                    } finally {
                         pstmtFlowHqAccess.close();
                         if (rsFlowHqAccess != null) {
                              rsFlowHqAccess.close();
                         //gestor.releaseConn(connFlowHqAccess);
     private SPVOpopulatedata(ResultSet rsCpProcess, boolean modify)
     throws SQLException {
          SPVOjavaIntra = new ServiceProcessVO();
          if (rsCpProcess.getString(ConstantesAssets.NU) != null
                    && !rsCpProcess.getString(ConstantesAssets.NU)
                    .equalsIgnoreCase(ConstantesAssets.BLANK))
               javaIntra.setNU(rsCpProcess.getString(
                         ConstantesAssets.NU).trim());
          if (rsCpProcess.getString(ConstantesAssets.NU_ASO) != null
                    && !rsCpProcess.getString(ConstantesAssets.NU_ASO)
                    .equalsIgnoreCase(ConstantesAssets.BLANK))
               javaIntra.setNU_ASO(rsCpProcess.getString(
                         ConstantesAssets.NU_ASO).trim());
          // HashTable logic to increament value for CTASOCIACION Start
          if (modify == true) {
               if (rsCpProcess.getString(ConstantesAssets.CTASOC) != null
                         && !rsCpProcess.getString(ConstantesAssets.CTASOC)
                         .equalsIgnoreCase(ConstantesAssets.BLANK)) {
                    char cha = ConstantesAssets.A;
                    if (tempMap.get(javaIntra.getNU()) != null) {
                         cha = tempMap.get(javaIntra.getNU()).toString()
                         .charAt(0);
                         cha++;
                    tempMap.put(javaIntra.getNU(), Character
                              .toString(cha));
                    javaIntra.setCTASOCIACION(((rsCpProcess
                              .getString(ConstantesAssets.CTASOC).trim()) + cha)
                              .trim());
          } else {
               javaIntra.setCTASOCIACION(rsCpProcess.getString(
                         ConstantesAssets.CTASOC).trim());
          // HashTable logic to increament value for CTASOCIACION End
          if (rsCpProcess.getString(ConstantesAssets.CCC) != null
                    && !rsCpProcess.getString(ConstantesAssets.CCC)
                    .equalsIgnoreCase(ConstantesAssets.BLANK))
               javaIntra.setCCC(rsCpProcess.getString(
                         ConstantesAssets.CCC).trim());
          if (rsCpProcess.getString(ConstantesAssets.FIV1) != null
                    && !rsCpProcess.getString(ConstantesAssets.FIV1)
                    .equalsIgnoreCase(ConstantesAssets.BLANK))
               javaIntra.setFIV(rsCpProcess.getString(
                         ConstantesAssets.FIV1).trim());
          if (rsCpProcess.getString(ConstantesAssets.FFV) != null
                    && !rsCpProcess.getString(ConstantesAssets.FFV)
                    .equalsIgnoreCase(ConstantesAssets.BLANK))
               javaIntra.setFFV(rsCpProcess.getString(
                         ConstantesAssets.FFV).trim());
          if (rsCpProcess.getString(ConstantesAssets.ES) != null
                    && !rsCpProcess.getString(ConstantesAssets.ES)
                    .equalsIgnoreCase(ConstantesAssets.BLANK))
               javaIntra.setES(rsCpProcess.getString(
                         ConstantesAssets.ES).trim());
          javaIntra.setI(ConstantesAssets.N);
          javaIntra.setN(ConstantesAssets.BLANK);
          javaIntra.setC(ConstantesAssets.BLANK);
          javaIntra.setCO(ConstantesAssets.BLANK);
          javaIntra.setFI(ConstantesAssets.BLANK);
          return javaIntra;
Please see the code
Siva

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=================== code snippet ========================
CallableStatement cs1 = (CallableStatement)conn.prepareCall("{? = call pkg_profile.fn_get_user_data(?) }");
cs1.registerOutParameter(1, java.sql.Types.OTHER);
cs1.setString (2, c_strUsername);
cs1.execute();
// Get the Result
ResultSet rs1 = (ResultSet)cs1.getObject(1);
if (rs1 == null || !rs1.next()) { <=== exception thrown due to moving cursor to the next row of query result.
=================== code snippet =======================
Exception -
ERROR 24 Nov 2004 12:19:28,527 USER:supuser - CNTXT:MISUserProfile.userDataDispatcher | SQL Error while retrieving data for user. | java.sql.SQLException: java.lang.NullPointerException: CDA is null
Start server side stack trace:
java.lang.NullPointerException: CDA is null
at weblogic.db.oci.OciCursor.arrayFetch(Native Method)
at weblogic.db.oci.OciCursor.oci_arrayFetch(OciCursor.java:2338)
at weblogic.jdbc.oci.ResultSet.next(ResultSet.java:774)
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at weblogic.jdbc.rmi.internal.ResultSetImpl_WLSkel.invoke(Unknown Source)
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at weblogic.security.service.SecurityServiceManager.runAs(SecurityServiceManager.java:821)
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End server side stack trace

Try this one...
Before excecuting the query setAutoCommit false and then try to execute the query.After executing query manually do commit.It should work.

Resultset.next() Issue

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Any suggestions or help explaining this would be greatly appreciated.
As always, thanks for reading my post.
Russ

Execution of a CallableStatement (Procedure) is relatively fast. Getting ResultSet back is fast. But First iteration over the result set takes a lot of time comparing to the following iterations.
Part of the code :
long start=System.currentTimeMillis();
int i=0;
long local=System.currentTimeMillis();
while(rs.next()){
if (i==0){
MetricsUtil.printTime("ResultSetRowHolder.getRows(ResultSet rs) ["+list.size()+" ]",local);
local=System.currentTimeMillis();
hol=new ResultSetRowHolder(rs);
list.add(hol);
i++;
if (i%100==0){
MetricsUtil.printTime("ResultSetRowHolder.getRows(ResultSet rs) ["+list.size()+" ]",local);
local=System.currentTimeMillis();
MetricsUtil.printTime("ResultSetRowHolder.getRows(ResultSet rs) ["+list.size()+" ]",start);
Printouts
Metrics << QueryHelper.executeStatement() >> Total time -> 2.836 sec
Metrics << ResultSetRowHolder.getRows(ResultSet rs) [0 ] >> Total time -> 13.867 sec
Metrics << ResultSetRowHolder.getRows(ResultSet rs) [100 ] >> Total time -> 0.48 sec
Metrics << ResultSetRowHolder.getRows(ResultSet rs) [200 ] >> Total time -> 0.44 sec
Metrics << ResultSetRowHolder.getRows(ResultSet rs) [300 ] >> Total time -> 0.47 sec
Metrics << ResultSetRowHolder.getRows(ResultSet rs) [400 ] >> Total time -> 0.38 sec
Metrics << ResultSetRowHolder.getRows(ResultSet rs) [500 ] >> Total time -> 0.37 sec
Metrics << ResultSetRowHolder.getRows(ResultSet rs) [600 ] >> Total time -> 0.38 sec
Metrics << ResultSetRowHolder.getRows(ResultSet rs) [700 ] >> Total time -> 0.35 sec
Metrics << ResultSetRowHolder.getRows(ResultSet rs) [800 ] >> Total time -> 0.34 sec
Metrics << ResultSetRowHolder.getRows(ResultSet rs) [900 ] >> Total time -> 0.32 sec
Metrics << ResultSetRowHolder.getRows(ResultSet rs) [1000 ] >> Total time -> 0.34 sec
Metrics << ResultSetRowHolder.getRows(ResultSet rs) [1100 ] >> Total time -> 0.41 sec
Metrics << ResultSetRowHolder.getRows(ResultSet rs) [1200 ] >> Total time -> 0.32 sec
Metrics << ResultSetRowHolder.getRows(ResultSet rs) [1230 ] >> Total time -> 14.340 sec

ResultSet.next() throws NullPointerException

Hello,
When running the following code:
import java.sql.*;
class DatabaseDriver {
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     private String               error;
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     private Statement          statement;
     private ResultSet          rs;
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     static final int          ORACLE_DB_TYPE = 4;
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                         break;
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               error = "could not load driver";
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               error = "could not connect to the database";
               return false;
          return true;
     public boolean execQuery (String query) {
          try {
               statement = con.createStatement();
               if (statement.execute(query)) {
                    rs = statement.getResultSet();
               while (rs.next()) {
                    System.out.println(rs.getString("1") + "\t" + rs.getString("2"));
               rs.close();
               rs = null;
               statement.close();
               statement = null;
          } catch (Exception e) {
               error = e.toString();
               e.printStackTrace();
               return false;
          return true;
     public String getError () {
          return error;
     public boolean disconnect () {
          return true;
class Test {
     public static void main (String[] args) {
          DatabaseDriver db = new DatabaseDriver(1);
          db.connect(args[0],args[1],args[2]);
          db.execQuery("USE " + args[3] + ";");
          db.execQuery("SELECT * FROM te;");
          System.out.println(db.getError());
}I receive this in the printout:
java.lang.NullPointerException
     at DatabaseDriver.execQuery(DatabaseDriver.java:61)
     at Test.main(Test.java:7)
bla1     bla2
bla6     bla7
java.lang.NullPointerException
Line 61
while (rs.next()) {
I have read a lot of other posts that say that the connection object is null or the recordset is empty, but it seems that neither of those are the case considering I am able to printout the two rows properly.
Can someone please explain to me what I am doing wrong and how to fix it?
Thanks

You can pepper your code with System.out.println() statements to determine what value goes into the execute() statement before it runs.
In the following, I think the first statement will probably return false. What is this sql trying to accomplish that you think it sould return true? Even if it returned true, what value do you expect in the resultSet?
db.execQuery("USE " + args[3] + ";");
db.execQuery("SELECT * FROM te;");
As a side note, I strongly suggest you use connection pooling and not driverManager. here is an example of getting and returning a connection properly (all within a function)
public String[] myFunction(){
Connection conn=null;
PreparedStatement pstmt1= null;
ResultSet resultSet=null;
ArrayList list1; //array that can grow in size
try{
list1=new ArrayList();
conn= dataSource.getConnection();
pstmt1= conn.prepareStatement();
resultSet= pstmt1.executeUpdate();
while(resultSet.next()){
arrayList.add(resultSet.getString("lastName");
return ( String[] ) arrayList.toArray( new String[arrayList.size()] );
} catch (SqlException e){
e.printStackTrace();
} finally {
if(rsultSet!=null)
resultSet.close();
if(pstmt1!=null)
pstmt1.close();
if(conn!=null)
conn.close();
}

Error message ResultSet.next not called

I am a student learning java and am currently working on an assignement where I need to write jdbc programs that connect to an oracle database. The error message that I am getting is:
ResultSet.next was not called.
I do not know why I am getting this message. I wrote a simpler program to try to find the error, but I still got it again. Here's the part of the program:
ResultSet rset = stmt.executeQuery ("SELECT billing_id_seq.NEXTVAL Next_SeqNumber "+
                         "FROM Dual");
int sequenceNumber=rset.getInt("Next_SeqNumber");
     while(rset.next()){
System.out.println(sequenceNumber);
Any ideas would be helpful. Thanks very much!

I am not really sure if it is okay to post the whole program on this message board, but here it is:
import java.sql.*;     //Import Java's JDBC classes
public class CalculateEnrollFinalGrades {
public static void main(String[] args) {
//Invoke the processEnrollRecords() method
     processEnrollRecords();
} //end main()
// The following method issues a SQL SELECT statement to the database that returns the section_id
// and student_id for ALL rows from the enrollment_copy table. For each row received back in the
// result set, a call should be made to the updateEnrollFinalGrade() method. See below for
// information about what the that method does and what arguments it takes.
public static void processEnrollRecords() {
try {
Class.forName("oracle.jdbc.driver.OracleDriver"); // Load the Oracle JDBC driver
catch (java.lang.ClassNotFoundException e) {
System.out.println(e.getMessage());
try {
//Create the connection and statement objects
     Connection conn= DriverManager.getConnection("jdbc:oracle:oci8:@", "STUDENT","LEARN");
     Statement stmt=conn.createStatement();
//Execute a query in the CTA database which returns section_id and student_id for all
//rows of the enrollment_copy table
     int sectId=0;
     int studId=0;
     String sqlQuery="SELECT section_id, student_id "+
               "FROM enrollment_copy";
     ResultSet rset= stmt.executeQuery(sqlQuery);
//For each record returned in the ResultSet object, pass
//the current connection object along with each section_id and student_id as
//arguments to a method called updateEnrollFinalGrade()
     //while(rset.next()){
     sectId=rset.getInt("section_id");
     studId=rset.getInt("student_id");
     updateEnrollFinalGrade(conn, sectId, studId);
     //}//close while
//Close all resources before the program ends
     //conn.close();      //should this be kept open???
     stmt.close();
     rset.close();
     return;
catch (java.sql.SQLException e) {
System.out.println(e.getMessage());
} // end processEnrollRecords()
// calculate a final_grade for the specified student
// and section, and then it updates the enrollment_copy table with the final_grade.
private static void updateEnrollFinalGrade(Connection conn_p, int sectionId_p, int studentId_p) {
try {
     Connection conn= DriverManager.getConnection("jdbc:oracle:oci8:@", "STUDENT","LEARN");
     Statement stmt=conn.createStatement();
     //query returns one row which is the final grade for the course for a particular student id and section.
     String sqlQuery2= "SELECT "+
     "ROUND(SUM((SUM(g.numeric_grade))/(COUNT(g.grade_type_code))*(gtw.percent_of_final_grade/100))) finGrade "+
     "FROM grade g, grade_type_weight gtw "+
     "where g.section_id=gtw.section_id AND g.grade_type_code=gtw.grade_type_code "+
     "AND g.student_id=? "+
     "AND g.section_id=? "+
     "GROUP BY gtw.percent_of_final_grade";
     PreparedStatement pstmt=conn.prepareStatement(sqlQuery2);
     pstmt.setInt(1, studentId_p);
     pstmt.setInt(2, sectionId_p);
     ResultSet rsetGrade=pstmt.executeQuery();
     int finalGrade=rsetGrade.getInt("finGrade");
//Once the final_grade has been calculated, use a different PreparedStatement object to
//store it in the related enrollment_copy record. You need to use a Prepared
//Statement
     String sqlUpdate=      "Update enrollment_copy "+
                    "SET final_grade=? "+
                    "WHERE student_id=? AND section_id=?";
     PreparedStatement pstmtUpdate=conn.prepareStatement(sqlUpdate);
     pstmtUpdate.setInt(1,finalGrade);
     pstmtUpdate.setInt(2,studentId_p);
     pstmtUpdate.setInt(3,sectionId_p);
     pstmtUpdate.executeUpdate();
     pstmt.close();
     pstmtUpdate.close();
     stmt.close();
     rsetGrade.close();
     return;
} // end try block
catch (java.sql.SQLException e) {
System.out.println(e.getMessage());
} //end updateEnrollFinalGrade()
} //end CalculateEnrollFinalGrades
Thanks very mush for your help.

ResultSet.next() and resultset.islast() problem

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