I get NullPointerException on adding details.

private void addActionPerformed(java.awt.event.ActionEvent evt) {

 

String name = name1.getText();

String mmath = math.getText();

String sci = science.getText();

String english = eng.getText();

int tot = Integer.parseInt(mmath)+Integer.parseInt(sci)+Integer.parseInt(english);

double percent1 = tot/3;

String ins = "insert into tbname(name,maths,science,english,total,percent)values('"+name+"','"+mmath+"','"+sci+"','"+english+"','"+tot+"','"+percent1+"')";

try{

Statement st = con.createStatement();

int i=0;

i = st.executeUpdate(ins);

if(i!=0)

{

JOptionPane.showMessageDialog(rootPane, "Data Added :)");

}

else

{

JOptionPane.showMessageDialog(rootPane, "Data Not Added :(");

}

}

catch(Exception ex)

{

System.out.print(ex);

}

}