null pointer exception in resultset.next()
843854Jul 22 2003 — edited Jul 25 2003hi ,
i am using multiple resultsets in an array . When i try to use the resultset[index].next() i get an nullpointer exception at while(esub[m].next()). Can any body figure out whats wrong .Here is the code :
ResultSet [] esub = new ResultSet[subnum];
int i=0;
while(subid.next()){
esub[i++] = explevel.executeQuery("select spot_id,expression_level from spotmeasurement where expression_level between "+ low + "and "+ upper + " and subexperiment_id = '" + subid.getString(1) + "'");
}
ResultSet rm,rn,rmg,rng;
for(int m=0;m<subnum;m++){
for(int n=0;n<subnum;n++){
if(m!=n){
while(esub[m].next()){
rm = stmt.executeQuery("select probe_id from spot where id ='"+esub[m].getString(1)+"'");
rm.next();
rmg = stmt.executeQuery("select gene_id from geneasprobe where probe_id='"+rm.getString(1)+"'");
rmg.next();
while(esub[n].next()){
rn = stmt.executeQuery("select probe_id from spot where id ='"+esub[n].getString(1)+"'");
rn.next();
rng = stmt.executeQuery("select gene_id from geneasprobe where probe_id='"+rn.getString(1)+"'");
rng.next();
if(rmg.getString(1).equals(rng.getString(1))){
mat[m][n]=mat[m][n]+1;
} //end of if
} //end of inner while
} //end of while
esub[m].first();
esub[n].first();
} //end of if
} //end of for
} //end of for
bye
chan