Consider the following code fragment:

Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery("SELECT a, b, c FROM table1");

getCount();  // this call causes the below rs.next() to return false

while(rs.next()) {
   ...
}

void getCount() {
   Statement stmt = conn.createStatement();
   ResultSet rs = stmt.executeQuery("SELECT count(*) FROM table1");
   while(rs.next()) {
      rs.getObject(1);
   }
}

If the above call to getCount() is commented out, then the while loop will succeed in retrieving the data from the result set.