Postgres Insert query not working? - postgresql

Question

This the code. I have mentioned where the query stops. There is no error in the console too. What could be the problem. I am using postgres database. getting data from jsp servlet and passing to dao through servlet as string. But as my db has different format i want to convert the variables to their respective types. But i first want to check whether insert query works with dummy data. It seems that every thing is working fine but code flow stops where mentioned and there is no data inserted in my db also.
public void doInsert(Connection conn, String i, String nam,String indate, String amont, String tx, String tot,String closd, String shipvia, String not) throws Exception {
ResultSet rs = null;
ResultSet rs1 = null;
Statement st=null;
Statement st1=null;
// TODO Auto-generated method stub
try{
/* String in=indate;
String reverse = new StringBuffer(in).reverse().toString();
System.out.println(reverse);
System.out.println(reverse);
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-M-dd");
String dateInString = indate;
Date date = sdf.parse(dateInString);
System.out.println(date);*/
/*String it=i;
String n=nam;
String in=indate;
String a=amont;
String t=tx;
String tota=tot;
String closed=closd;
String ship_via=shipvia;
String note=not;
to_date("+date+",'YYYY-MM-DD')*/
System.out.println("came above sql");
/*to_date("+date+",'YYYY-MM-DD')*/
String sql="insert into invheader(id,invdate,client_id,amount,tax,total,closed,ship_via,note) values(100001,to_date('1963-09-01', 'YYYY-MM-DD'),100001,100.00,20.00,120.00,TRUE,'tnt','note 1')";
//"insert into invheader(id,invdate,client_id,amount,tax,total,closed,ship_via,note) values('',to_date('1963-09-01', 'YYYY-MM-DD'),"+i+","+amont+","+tx+","+tot+","+closd+","+shipvia+","+not+")";
System.out.println("after 1st query");
String sql1="insert into clients(client_id,name) values("+i+","+nam+")";
System.out.println("after 2nd query");
st =conn.createStatement();
st1 =conn.createStatement();
//Statement stmt1 = conn.createStatement();//connection to statement
System.out.println("above execute"); //<======= code stops here
rs=st.executeQuery(sql);
System.out.println("above execute1");
rs1=st1.executeQuery(sql1);
System.out.println("inserted dao");
}catch(Exception e){
e.printStackTrace();
throw e;
}
// TODO Auto-generated method stub
}
Please help me. what could be the reason?