java - How can I catch "no rows selected" in JSP? -


my jsp page contains following code login authentication:

<%  system.out.println("entered");  string username=request.getparameter("username");  string password=request.getparameter("password");  connection con=getconnection.getconnectionbuilder();   preparedstatement pstmt=con.preparestatement("select password users username=? , password=?");  pstmt.setstring(1, "username");  pstmt.setstring(2, "password");  boolean iftrue=pstmt.execute();  system.out.println(""+iftrue);  if (iftrue==false)  {     out.print("invalid userid , password combination");  } %>

now problem "the query returns no rows selected oracle when putting invalid username , password combination , unable understand how can catch message. have tried using boolean, expected returning true. not find method of pstmt returns string , executeupdate returns integer.

please try below code.

preparedstatement pstmt = con.preparestatement("select password users username=? , password=?"); pstmt.setstring(1, "username"); pstmt.setstring(2, "password"); resultset resultset = pstmt.executequery();  if(!resultset.next())      out.print("no rows selected"); }

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