Jsp stringbuilder和查询以发布数据

我有下面的jsp

 <%@page import="java.util.Locale"%>
<%@page import="java.text.SimpleDateFormat"%>
<%@page import="java.sql.*"%>
<%
    Connection con = null;
    Statement stmt = null;
    try {
        String a = request.getParameter("comments");
        String b = request.getParameter("updatedl");
        String c = request.getParameter("sid");
        String d = request.getParameter("desc");
        String e = request.getParameter("pubcode");
        String f = request.getParameter("Type");
        String g = request.getParameter("status");


        String h = null;
        if (null != request.getParameter("DateRec")) {
            h = request.getParameter("DateRec");
        }
        String i = null;
        if (null != request.getParameter("startD")) {
            i = request.getParameter("startD");
        }
        String j = null;
        if (null != request.getParameter("AssignedD")) {
            j = request.getParameter("AssignedD");
        }
        String k = null;
        if (null != request.getParameter("sentToAE")) {
            k = request.getParameter("sentToAE");
        }
        String l = null;
        if (null != request.getParameter("RespFrmAE")) {
            l = request.getParameter("RespFrmAE");
        }
        String m = null;
        if (null != request.getParameter("VWRCmp")) {
            l = request.getParameter("VWRCmp");
        }
        String n = request.getParameter("PS");
        String o = request.getParameter("TEst");
        String p = request.getParameter("Units");
        String q = null;
        if (null != request.getParameter("VWR")) {
            l = request.getParameter("VWR");
        }
        String r = request.getParameter("IE");
        String s = null;
        if (null != request.getParameter("RevDate")) {
            s = request.getParameter("RevDate");
        }
        String t = request.getParameter("ReviewS");

        Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
        con = DriverManager.getConnection("jdbc:odbc:Driver={Microsoft Excel Driver (*.xls)};DBQ=C:/jus/Excel1.xls; ReadOnly=true;");

        StringBuilder sc=new StringBuilder();


        stmt = con.createStatement();
        String query = "insert into [Feb$] ([comments],[No of lines updated in PSIS],[Shipment ID],"
                + "[SAP TXT Description],[Phoenix Pub Code], [Product Type], [Status of the job],[Date Request received],"
                + "[Start Date], [Date assigned],[Date file sent to AE],[Date response from AE],"
                + "[Date completed --VWR], [Assigned to PS], [Time Estimate],[Units], [Date file needs to be sent to Vendor (VWR)],"
                + "[Internal Errors],[Review Date],[Review Sent (Yes/No)]) values ('" + a + "','" + b + "','" + c + "','" + d + "','" + e + "','" + f + "','" + g + "','" + h + "','" + i + "','" + j + "','" + k + "','" + l + "','" + m + "','" + n + "','" + o + "','" + p + "','" + q + "','" + r + "','" + s + "','" + t + "')";

        PreparedStatement ps = con.prepareStatement(query);
        int new1 = ps.executeUpdate();

        String UR = "success.jsp";
        response.sendRedirect(UR);

    } catch (Exception e) {
        out.println(e);
    } finally {
        try {
            stmt.close();
            con.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

%>

在这里，我想将数据发布到excel工作表中，并且我想使用stringbuilder进行查询，以便空值（在上面的程序中初始化）为空，应该在查询中跳过这些值，如果它们有值，那么应该考虑它们。请告诉我怎么做

---

谢谢。

使用字符串生成器，如下所示：

StringBuilder sb=new StringBuilder();

String query = "insert into [Feb$] ([comments],[No of lines updated in PSIS],[Shipment ID],"
                + "[SAP TXT Description],[Phoenix Pub Code], [Product Type], [Status of the job],[Date Request received],"
                + "[Start Date], [Date assigned],[Date file sent to AE],[Date response from AE],"
                + "[Date completed --VWR], [Assigned to PS], [Time Estimate],[Units], [Date file needs to be sent to Vendor (VWR)],"
                + "[Internal Errors],[Review Date],[Review Sent (Yes/No)]) values ('" + a + "','" + b + "','" + c + "','" + d + "','" + e + "','" + f + "','" + g;

sb.append(query);
if(h==null && i==null &&b j==null && k==null)
sb.append(+ "')");
if(h!=null)
sb.append("','" + h);
if(i!=null)
sb.append("','" + i);
if(j!=null)
sb.append("','" + j);
if(k!=null)
sb.append("','" + k);
.
.
.

最后将sb转换为字符串，如下所示：

String dynamicQuery = sb.toString();