ajax给servlet传递中文参数的问题

现在做一个像google搜索那样，输入词会出现词语联想，如我我输入“中国”他就会把以中国开头的下拉出来，我做一个但是传递英文没有问题，传递中文就就不会返回（保证数据库里有内容，输出他的SQL语句，在mysql的控制台可以执行，并能查询出结果），传递中文参数（可以正确输出中文参数），并且while语句就不执行，望帮忙，在线等。贴出原代码：
JSP页面：
<%@ page contentType="text/html;charset=GB2312" language="java" %>
<HTML><HEAD><TITLE>ajax</TITLE>
<META http-equiv=Content-Type content="text/html; charset=GB2312">
<LINK href="images/css.css" type=text/css rel=stylesheet>
</HEAD>
<script language="javascript">
var XMLHttpReq;
    var completeDiv;
    var inputField;
    var completeTable;
    var completeBody;
  //创建XMLHttpRequest对象       
    function createXMLHttpRequest() {
if(window.XMLHttpRequest) { //Mozilla 浏览器
XMLHttpReq = new XMLHttpRequest();
}
else if (window.ActiveXObject) { // IE浏览器
try {
XMLHttpReq = new ActiveXObject("Msxml2.XMLHTTP");
} catch (e) {
try {
XMLHttpReq = new ActiveXObject("Microsoft.XMLHTTP");
} catch (e) {}
}
}
}
//发送匹配请求函数
    function findNames() {
        inputField = document.getElementById("names");            
        completeTable = document.getElementById("complete_table");
        completeDiv = document.getElementById("popup");
        completeBody = document.getElementById("complete_body");
        if (inputField.value.length > 0) {
            createXMLHttpRequest(); 
            var url = "AutoCom?action=match&names=" + inputField.value;                        
            XMLHttpReq.open("POST", url, true);
            XMLHttpReq.setRequestHeader("Content-type","application/x-www-form-urlencoded");
            XMLHttpReq.onreadystatechange = processMatchResponse;//指定响应函数
            XMLHttpReq.send("POST"); // 发送请求
        } else {
            clearNames();
        }
    }
// 处理返回匹配信息函数
    function processMatchResponse() {
     if (XMLHttpReq.readyState == 4) { // 判断对象状态
     alert(XMLHttpReq.status);
         if (XMLHttpReq.status == 200) { // 信息已经成功返回，开始处理信息
                    setNames(XMLHttpReq.responseXML.getElementsByTagName("res"));
            }else { window.alert("您所请求的页面有异常。");
            }
        }
    }
//生成与输入内容匹配行
         function setNames(names) {            
            clearNames();
            var size = names.length;
            setOffsets();            var row, cell, txtNode;
            for (var i = 0; i < size; i++) {
                var nextNode = names[i].firstChild.data;
                row = document.createElement("tr");
                cell = document.createElement("td");
                
                cell.onmouseout = function() {this.className='mouseOver';};
                cell.onmouseover = function() {this.className='mouseOut';};
                cell.setAttribute("bgcolor", "#FFFAFA");
                cell.setAttribute("border", "0");
                cell.onclick = function() { completeField(this); } ;                                             txtNode = document.createTextNode(nextNode);
                cell.appendChild(txtNode);
                row.appendChild(cell);
                completeBody.appendChild(row);
            }
        }
//设置显示位置                
        function setOffsets() {
            completeTable.style.width = inputField.offsetWidth; + "px";
            var left = calculateOffset(inputField, "offsetLeft");
            var top = calculateOffset(inputField, "offsetTop") + inputField.offsetHeight;
            completeDiv.style.border = "black 1px solid";
            completeDiv.style.left = left + "px";
            completeDiv.style.top = top + "px";
        }
  //计算显示位置       
    function calculateOffset(field, attr) {
      var offset = 0;
      while(field) {
        offset += field[attr]; 
        field = field.offsetParent;
      }
      return offset;
    }
//填写输入框
    function completeField(cell) {
        inputField.value = cell.firstChild.nodeValue;
        clearNames();
    }
//清除自动完成行
    function clearNames() {
        var ind = completeBody.childNodes.length;
        for (var i = ind - 1; i >= 0 ; i--) {
             completeBody.removeChild(completeBody.childNodes[i]);
        }
        completeDiv.style.border = "none";
    }
    }
</script>
<table  style="BORDER-COLLAPSE: collapse" borderColor=#111111 
            cellSpacing=0 cellPadding=2 width=400  border=0>
    <TR>
         <TD align=middle height=4 colspan="3">
 </TD>
</TR>
<TR>
       <TD align=middle 
                    height=19 colspan="3"><B>搜索</B>
   </TD>
</TR>
<tr>
        <td height="20">
输入关键字:
</td>
<td height="20">
 <input type="text" size="15" id="names" onkeyup="findNames();" style="height:20;">
    <div style="position:absolute;" id="popup">
        <table id="complete_table"  border="0" cellspacing="0" cellpadding="0"/>            
            <tbody id="complete_body"></tbody>
        </table>
    </div>
</td>
    </tr>
</table>
servlet代码：
package org.ajax;import java.io.IOException;
import java.net.*;
import java.io.PrintWriter;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;public class AutoCom extends HttpServlet {    protected void doPost(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
     //设置接收信息的字符集
     request.setCharacterEncoding("GB2312");      
        response.setContentType("text/xml; charset=GB2312");
        response.setHeader("Cache-Control", "no-cache");
String action = request.getParameter("action");
System.out.println("hello:"+action);
String name = StringUtil.getDecoding("names", request);
System.out.println("1111111："+name);
        PrintWriter out = response.getWriter();
        //依据验证结果输出不同的数据信息
        out.println("<response>");
        DB db = new DB();
ResultSet rs;
        String strSql=null;
        //匹配
              try {
if ("match".equals(action)){
strSql = "select name from product where name like '"+name+"%'";
     rs = db.executeQuery(strSql);
                                       while( rs.next()) {             out.println("<res>" + rs.getString("name") + "</res>");
     }
        }
        System.out.println("eeeeeeeeeeeeee");
out.println("</response>");
//out.close();
        } catch (SQLException e) {
System.out.println("33333333");
e.printStackTrace();
}
    }
}编码过滤类：
package org.ajax;import javax.servlet.http.*;
public class StringUtil {  public static String getDecoding(String pram,HttpServletRequest request){
 
 String val = request.getParameter(pram);

 try{
 byte b[] = val.getBytes("8859_1");
 val = new String (b,"GB2312");
 System.out.println(val);
 }catch(Exception e){
 e.printStackTrace();
 System.out.println("出现错误!");
 }
 return val;
 }
}