我做的JSP连接Oracle时总是出问题请高手帮忙

<%@ page import="java.sql.*" %>
<%@ page contentType="text/html;charset=gb2312"%>
<%@ page import="javax.sql.*" %>
<%@ page errorPage="err_book_insert.jsp"%>
<html>
<head>
<title>注册图书信息</title>
</head>
<body>
<% 
String id=request.getParameter("bookid");
String bookname=request.getParameter("bookname");
String booknumber=request.getParameter("booknumber");
String bookprice=request.getParameter("bookprice");
String bookperson=request.getParameter("buyperson");
String buybookdate=request.getParameter("buybookdate");
String bookconcern=request.getParameter("bookconcern");
try{
int number=Integer.parseInt(booknumber);
float price=Float.parseFloat(bookprice);
Class.forName("oracle.jdbc.driver.OracleDriver");
DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver());
String url="jdbc:oracle:thin:@localhost:1521:fangbo";
String username="scott";
String password="tiger";
Connection cn=DriverManager.getConnection(url,username,password);
String str="select * from book where book_id=?";
PreparedStatement ps=cn.prepareStatement(str);
ps.setString(1,id);
ResultSet rs=ps.executeQuery();
out.print("sdfgf");
if(rs.next()){
out.println("1");
//response.sendRedirect("err_book_insert.jsp");
}
if(rs.wasNull()){
ps.setString(1,id);
ps.setString(2,bookname);
ps.setInt(3,number);
ps.setFloat(4,price);
ps.setString(5,bookperson);
ps.setString(6,buybookdate);
ps.setString(7,bookconcern);
ps.executeUpdate(); 
out.println("2");
}
rs.close();
ps.close();
cn.close();
}
catch(Exception e){
out.println("3");
}

 %>

<p><div align="center">恭喜插入数据成功,具体数据如下:</div></p>
<div align="center">图书的序列号为:<%=id%><br>图书的名称为:<%=bookname%><br>图书的数量<%=booknumber%><br>图书的价钱<%=bookprice%>
<br>图书购买者<%=bookperson%><br>购买图书日期<%=buybookdate%><br>图书出版社<%=bookconcern%></div>
<div align="center"><input type="button" name="btn" value="返回" onClick="location.href='seach_book.jsp'"></div>

</body>
</html>
请问为什么我的总是输出3