从数据库读出的JPG文件的字符流，转换成图片显示在页面上的相关代码

public void doPost(HttpServletRequest req, HttpServletResponse res)

throws ServletException, IOException {

ServletOutputStream out = res.getOutputStream();

Statement dispStmt = null, setStmt = null;

try {

dispStmt = Con.createStatement();

setStmt = Con.createStatement();

setStmt.executeUpdate("set textsize 2048000");

} catch (Exception e) {

out.println("Create Statement error:" + e.toString() + "<br>");

}

String ls_sql = null;

ls_sql = req.getParameter("ImageSQL");

if (ls_sql == null)

ls_sql = "";

ls_sql = ls_sql.trim();

if (!ls_sql.equals("")) {

ResultSet rs = null;

try {

rs = dispStmt.executeQuery(ls_sql);

} catch (Exception e) {

System.out.println(

"Unable to Exec Statment" + e.toString() + "<br>");