Nullpointer Exception Error Java Help me solve this

Question

public void tableDetails()
{
DefaultTableModel dtm=(DefaultTableModel) jTable1.getModel();
dtm.setRowCount(0);
try{
Connection con=ConnectionProvider.getcon();
Statement st=con.createStatement();
ResultSet st=rs.executeQuery("select from room");
while(rs.next())
{
dtm.addRow(new Object[](rs.getString(1),rs.getString(2),rs.getString(3)});
}
}
catch(Exception e)
{
JOptionPane.showMessageDialog(null,e)
}
}

Answer 1

Brother do you any whatsapp or telegram I will send the project over there so that u can look the matter

Answer 2

It doesn't shows the line and also it doesn't shows any errors but when I try to run the program it shows the error

Answer 3

Hmm, maybe checking the following functions can help.

"getModel" and "createStatement"

Because if you're getting a null pointer exception, that means you're using an object reference that doesn't actually refer to an object, but to a null pointer reference. In the snippet you provided, only these functions are returning an object so maybe one of them returned a null pointer reference. Try this and tell if it worked

Answer 4

Save your complete code in code playground and share it's link here so that it's easy to reproduce your error and help you =)

Answer 5

Dipankar Borah no I don't have =(
Can you say exactly in which line the exception is being shown?