关于数据库操作的问题

这是我CODE,JDBC,ODBC封装在JAVABEAN里,应该没有问题,刚才发现,数据是更新了,但在库里是乱码,怎么办!
<%@page contentType="text/html; charset=gb2312" language="java" import="java.sql.*"%>
<%@ page import = "sbgl.execute"%>
<jsp:useBean id="execute" scope="session" class="sbgl.execute" />
<%!
public String getStr(String str)
{
try
{
String temp_p = str;
byte[] temp_t = temp_p.getBytes("GBK");
String temp = new String(temp_t,"ISO8859_1");
return temp;
}catch(Exception e)
{ }
return "null";
}
%>
<%
String mingc,guoj,yiqbh,xingh,changj,xissbh,jiszb,zhizh,fenlh,zuofbj;
String jingfkm,xiaodjh,beiz,chucrq,gouzrq,danj,zengjz;mingc=getStr(request.getParameter("text1"));
guoj=getStr(request.getParameter("text2"));
yiqbh=request.getParameter("text3");
xingh=request.getParameter("text4");
changj=request.getParameter("text5");
xissbh=request.getParameter("text6");
jiszb=request.getParameter("text7");
zhizh=request.getParameter("text8");
fenlh=request.getParameter("text9");
chucrq=request.getParameter("text10");
gouzrq=request.getParameter("text11");
jingfkm=request.getParameter("text12");
danj=request.getParameter("text13");
zengjz=request.getParameter("text14");
xiaodjh=request.getParameter("text15");
beiz=request.getParameter("text16");
zuofbj=request.getParameter("text17");String sql = "update tshebjbxx set cmingc = '"+mingc+"' where cyiqbh = '"+yiqbh+"'"; execute.executeUpdate(sql);  out.println(sql);%>