how to speed this up

    import java.sql.ResultSet;
    import java.util.List;
    import java.util.ArrayList;
    // etc etc. etc


    public class SomeServlet extends HttpServlet {


        // ALL THE FOLLOWING ARE CONSTANTA IN THE SERVLET.
        // THEIR VALUE DOES'T CHANGE DURING EXECUTION
        private static final String SELECT_DOCUMENT_QUERY = "SELECT \n" +
                                                        "   id,LineType, QtyTotal, ManufacturerPartNumber, Description, UnitCost,UnitPrice \n" +
                                                        " FROM DocumentItems  \n" +
                                                        " WHERE DocID=%s order by linenumber ";

        private static final String HTML_HEADER_TABLE ="<table class=inner><thead><colgroup><col id='col1'>"+
                                                        "<col id='col2'><col id='col3'><col id='col4'><col id='col5'></colgroup>" +
                                                        "<tr class='enetBlue'><th>Qty</th><th>Part Num</th><th>Description</th>"+
                                                        "<th>Unit Cost</th><th>Unit Price</th></tr></thead><tbody>";


        // These constants are the HTML Commbo for the given queries.
        // If they are initialized once at the beginning will increase
        // the servlets performace considerabily.
        private static final String UNIT_MEASURES_COMBO = getCombo( "Unit Measure", "UnitMeasKey",
                                                                    getListFrom( "select * from tciUnitMeasure where companyid like 'ENS' ") );

        private static final String ITEM_CLASS_COMBO    = getCombo( "Purchase Product Line", "PurchProdLine",
                                                                    getListFrom( "select * from timPurchProdLine where companyID = 'ENS' ") );

        private static final String CLASS_KEY_COMBO     = getCombo( "Item Class :", "itemclasskey",
                                                                   getListFrom( "select * from timItemClass where companyID = 'ENS' order by itemclassname desc") );

        // Use a class to separete domain objects from presentation
        // This class becomes handy do pass data through methods.
        class Document {
            int lineType;
            int qty;
            String part;
            String desc;
            float cost;
            float price;
            String id;
        }
        // simple clas that holds a key/value pair
        class ComboPair {
            String key;
            String value;
            public ComboPair( String key, String value ) {
                this.key = key;
                this.value = value;
            }
        }


        /*
        * Finally the fixed code.
        *
        * Basically a method should do only one thig. If the method is doing a lot of things
        * several functionality at the same time, it should delegate the details of the subfunctionality
        * to another function. This way each function or method is easier to read/maintain/understand.
        * This method should read like this:
        *
        * For a given docId,
        *    - query the database and display details of the document
        *    - if the document is not present in mas?
        *         - create a form to inser it
        *
        * differntiate each record with different style.
        */
        private String getDetails(String doc){
            // Close each result set before openning a new one.
            ResultSet rs = qw.DBquery( String.format( SELECT_DOCUMENT_QUERY, doc ));
            List<Document> documents = new ArrayList<Document>();
            while(rs.next()){
                documents.add( createDocumentFrom( rs ));
            }
            // Iterate through
            StringBuilder resultingTable = new StringBuilder( HTML_HEADER_TABLE );
            boolean isEven = false;// starts as odd
            for( Document doc : documents ) {
                String clazz = getClassFor( doc , isEven );
                isEven = !isEven;

                resultingTable.append("<tr class='"+clazz+"'>"+
                            "<td>"+doc.qty+"</td>\n"+
                            "<td>"+doc.part+"</td>\n"+
                            "<td>"+doc.desc+"</td>\n"+
                            "<td>"+doc.cost+"</td>\n"+
                            "<td>"+doc.price+"</td></tr>\n");

                if( needsInsertForm( clazz ) ) {
                    resultingTable.append( getInsertForm( document ) );
                }

                resultingTable.append("</tbody></table>");
            }
            return table;
        }


        /**
         * This methods craates an instance of "Document".
         * Instead of mixing the fetch code with the render code
         * this method allows to separete the data from its presentation
         */
        private Document createDocumentFrom( ResultSet rs ) {
            Document document = new Document();

            document.lineType = rs.getInt("LineType");
            document.qty = rs.getInt("QtyTotal");
            document.part = rs.getString("ManufacturerPartNumber");
            document.desc = rs.getString("Description");
            document.cost = rs.getFloat("UnitCost");
            document.price = rs.getFloat("UnitPrice");
            document.id = rs.getString("id");

            return document;
        }



        // Computes the correct css class for the given document.
        private static String getClassFor( Document document, boolean isEven ) {
            String clazz = "red";
            switch( document.lineType ) {
                case 2:
                case 3:
                case 4: clazz ="yellow";
            }
            if( document.qty == 0 ) {
                clazz = "yellow";
            }
           ResultSet rs = mas.DBquery( String.format("select itemkey from timitem where itemid = '%s'", document.part);
           while (rs.next()) {
               clazz = isEven? "even" : "odd";
           }
           rs.close();
           return clazz;

        }
        // This is an utility method that reads bettern when used in the
        // main method.
        // if( needsInsertForm( clazzz ) ) {
        // is much clearer
        private static boolean needsInsertForm( String clazz ) {
            return "red".equals(clazz);
        }

        // Creates the inser form for the given document
        private static String getInsertForm( Document document ) {
            StringBuilder form = new StringBuilder();

            form.append("<tr ><td colspan=5><table border=1><tr><td colspan=2>\n");
            form.append("<form name=masinsert"+document.id+" method=get action=MASInsert>\n");
            form.append("<input type=hidden name=\"partnumber"+document.id+"\" value=\""+document.part+"\">\n");
            form.append("<input type=hidden name=\"itemdescription"+document.id+"\" value=\""+document.desc+"\">\n");
            form.append("<input type=hidden name=\"itemcost"+document.id+"\" value=\""+document.cost+"\">\n");
            form.append("<input type=hidden name=\"itemlistprice"+document.id+"\" value=\""+document.price+"\">\n");
            form.append("</td><tr>\n");
            //----------------------------------------------------------------------------------------------------------------------------
            //get unit measure key
            form.append(UNIT_MEASURES_COMBO);

            //build ItemClass options from mas: Puchase ProductLine
            form.append(ITEM_CLASS_COMBO);

            //build item classkey options
            form.append( CLASS_KEY_COMBO);
            //----------------------------------------------------------------------------------------------------------------------------
            form.append("<tr><td colspan=2><input id='m"+document.id+"' type=\"button\" onclick=\"masinsert('"+ document.id +"')\" value=\"Add to MAS\"></td></tr>");
            form.append("</table>\n";
            form.append("</form>\n";
            form.append("</td></tr>");
            return form.toString();

        }

        // Generates an html combo
        // is a bit messy, but does the job. In total this function is called only 3 times during
        // this servlet life.
        private static final String getCombo( String columnName, String comboName, List<ComboPair> items  ) {
            // Don't need to worry too much here about string concatenation, this is invoked only once.
            StringBuilder builder = new StringBuilder(
                              "<tr bgcolor=#990033>\n"+
                              "     <td align=left valign=top>"+columnName+"</td>\n"+
                              "     <td align=left valign=top>\n"+
                              "         <select name=\""+comboName+"\">\n" );
            for( ComboPair pair : items ) {
                builder.append(String.format("<option value=\"%s\">%s</option>\n", pair.key, pair.value));
            }
            builder.append("</select></td></tr>\n");
            return builder.toString();
        }

        // Utlity method that builds a list of key=value objects from the given query.
        // This is used to query the catalogs.
        private static final List<ComboPair> getListFrom( String query ) {
                ResultSet rs = mas.DBquery( query );
                List<ComboPair> list = new ArrayList<ComboPair>();
                try {
                    while(rs.next()) {
                        list.add( new ComboPair( rs.getString("UnitMeasKey"),
                                                 rs.getString("UnitMeasID")));
                    }
                } finally {
                    if( rs != null ) try {
                        rs.close();
                    } catch( SQLException sqle ){}
                }
                return list;
        }




    }