How to insert simplified chinese character in oracle through JSP

Oracle 8i 8.1.7
IBM RS6000 AIX5L
NLS_LANGUAGE=SIMPLIFIED CHINESE
NLS_TERRITORY=CHINA
NLS_CHARACTERSET=ZHS16GBK
NLS_NCHAR_CHARACTERSET=USASCII7

I have tried to update a field (varchar(100) or varchar2(100)) with simplified chinese character through JSP but failed ('????' are shown). Please help!

Here is my code:

<%@ page contentType="text/html; charset=gb2312"%>
<%@ page import="java.sql.*" %>
<%@ page import="java.net.*" %>
<%@ page import="beans.*" %>
<jsp:useBean id="SQL" scope="request" class="beans.SQLConnection">
<jsp:setProperty name="SQL" property="driverName" value="oracle.jdbc.driver.OracleDriver"/>
<jsp:setProperty name="SQL" property="jdbcURL" value="jdbc:oracle:oci8:@ora8"/>
<jsp:setProperty name="SQL" property="username" value="aaaa"/>
<jsp:setProperty name="SQL" property="password" value="bbbb"/>
</jsp:useBean>
<%
      String strA = "&#20630;&#39649;&#36617;&#38484;&#35473;&#38596;&#34656;&#30498;&#26740;";
      String strA1 = new String(strA.getBytes("ISO-8859-1"), response.getCharacterEncoding());
      
%>      
Character Encode - <%=response.getCharacterEncoding()%><br>
Original - <%=strA %><br>
ISO to gb2312 - <%=strA1 %><br>
<p>
<%      

            SQL.openDB();
            
            String strsql = "UPDATE testtable SET f1 = '" + strA1 +"'";
            String[] SQLstmts = new String[1];
            SQLstmts[0] = strsql;
            SQL.execUpdate(SQLstmts);
      %>
0 - <%=strsql %><p>
<h1>RESULT</h1>
<%
            strsql = "SELECT f1 FROM testtable";
            SQL.execSQL(strsql);


            while(SQL.nextRow())
            {

                  strA = SQL.getField("f1");
                  strA1 = new String(strA.getBytes(response.getCharacterEncoding()), "ISO-8859-1");


%>
Original - <%=strA %><br>
gb2312 to ISO - <%=strA1 %><br>
<p>
<%
            }

            SQL.closeDB();
%>