I have a problem with line pstmt.setLong(1, id);
. I get an error that the value is not set for the parameter number 1. If I use the String SQL without the question mark, it works. Also, when I use ARM the PreparedStatement
and ResultSet
are not automatically closed so I have to close them, and finally doesn't seem to work either
@Override
public Company getCompany(long id) {
Connection con = ConnectionPool.getInstance().getConnection();
String sql = "SELECT * FROM Company WHERE ID=?";
//String sql = "SELECT * FROM Company WHERE ID=" + id;
Company company = new Company();
try (
PreparedStatement pstmt = con.prepareStatement(sql);
ResultSet rs = pstmt.executeQuery();)
{
pstmt.setLong(1, id);
if (rs.next()) {
company.setId(rs.getLong(1));
company.setCompName(rs.getString(2));
company.setPassword(rs.getString(3));
company.setEmail(rs.getString(4));
} else {
System.out.println("Company with ID: " + id + " could not be found\n");
}
pstmt.close();
rs.close();
} catch (SQLException e) {
CouponSystemException ex = new CouponSystemException("Company with ID: " + id + " could not be retrieved\n", e);
System.out.println(ex.getMessage());
System.out.println(e);
}
ConnectionPool.getInstance().returnConnection(con);
return company;
}
Set the parameter before executing the query. Also, You don't need to close Statement and result sets defined in try-with-resource statements as they'll be closed automatically when you leave the try scope.
try(PreparedStatement pstmt = con.prepareStatement(sql)) {
pstmt.setLong(1, id);
try(ResultSet rs = pstmt.executeQuery()) {
// do stuff
}
}
You need to set the PreparedStatement
's parameters before executing it. Also note that this you're using the try-with-resource syntax you shouldn't close the resources yourself:
try (PreparedStatement pstmt = con.prepareStatement(sql)) {
pstmt.setLong(1, id);
try (ResultSet rs = pstmt.executeQuery()) {
if (rs.next()) {
company.setId(rs.getLong(1));
company.setCompName(rs.getString(2));
company.setPassword(rs.getString(3));
company.setEmail(rs.getString(4));
} else {
System.out.println("Company with ID: " + id + " could not be found\n");
}
}
} catch (SQLException e) {
CouponSystemException ex = new CouponSystemException("Company with ID: " + id + " could not be retrieved\n", e);
System.out.println(ex.getMessage());
System.out.println(e);
}
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