Thread: Can anybody correct the code?

The code is

Node codeiso3= node.selectSingleNode("isoAlpha3");
Node capital= node.selectSingleNode("capital");
System.out.println(codeiso3.getText() + capital.getText());
String tempstring="UPDATE country_details SET capital = ? WHERE codeISO3 = ? ;";

System.out.println(tempstring);
z=conn.prepareStatement(tempstring);
String x = "\""+capital.getText()+"\"";
String y = "\""+codeiso3.getText()+"\"";
System.out.println(x);
System.out.println(y);
z.setString(1,x);
z.setString(2,y);
z.executeUpdate (tempstring);

The Error is

com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorEx ception: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '? WHERE codeISO3 = ?'

Im getting the nodes correctly.There is error in including the string which i got within double quotes.I have tried various methods to include double quotes but in vain.Can anybody say how to do this?

Thankyou in advance!!!