Export ORACLE data table DDL Using JSP

I have been busy sorting out ISO documents over the past few days, and I don't know whether the database manuals I have maintained are complete. I just want to write a program to guide it out ;). The following program expddl. jsp can export the DDL of all data tables of the user currently connected to the database.
EXPDDL. JSP:
<% @ Page contentType = "text/html; charset = gb2312" language = "java" %>
<% @ Page import = "java. SQL. *" %>
<% @ Page import = "oracle. jdbc. OracleDatabaseMetaData" %>
<% @ Page import = "oracle. jdbc. OracleResultSetMetaData" %>
<% @ Page import = "javax. SQL. *, javax. naming. Context" %>
<% @ Page import = "javax. naming. InitialContext" %>
<Div align = "center">
<%
DataSource ds = null;
Context ic = new InitialContext ();
Ds = (DataSource) ic. lookup ("java: comp/env/jdbc/mydb ");
Connection conn = ds. getConnection ();
OracleDatabaseMetaData odmd = (OracleDatabaseMetaData) conn. getMetaData ();
String us = odmd. getUserName ();
String [] types = new String [1];
Types [0] = "TABLE ";
ResultSet rs = odmd. getTables (null, us, "%", types );
While (rs. next ()){
// Obtain the table name
String tname = rs. getString (3 );
%>
<Div align = "center"> table name: <% = tname %> </div>
<Table width = "483" height = "50" border = "1" cellpadding = "2" cellspacing = "0">
<Tr>
<Td> <div align = "center"> NO. </div> </td>
<Td> <div align = "center"> id </div> </td>
<Td> <div align = "center"> type/precision </div> </td>
<Td> <div align = "center"> description </div> </td>
</Tr>
<%
Statement st = conn. createStatement ();
ResultSet rs1 = st.exe cuteQuery ("select * from" + tname );
OracleResultSetMetaData ormd = (OracleResultSetMetaData) rs1.getMetaData ();