HttpClient-传入url得到json字符串（ PostMethod method = new PostMethod(url)是个好方法）

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.httpclient.DefaultHttpMethodRetryHandler;
import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.HttpException;
import org.apache.commons.httpclient.UsernamePasswordCredentials;
import org.apache.commons.httpclient.auth.AuthScope;
import org.apache.commons.httpclient.methods.GetMethod;
import org.apache.commons.httpclient.methods.PostMethod;
import org.apache.commons.httpclient.params.HttpMethodParams;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

import net.sf.json.JSONObject;

@Controller
@RequestMapping("/synchronize")
public class SynchronizeController {
    private Log log = LogFactory.getLog(BuildNavigatorServiceImpl.class);

    private String requestIP = "";

    private int requestPort;

    /**
     * 用户名
     */
    private String user = "";

    /**
     * 密码
     */
    private String password = "";

    /*rest请求的客户端*/
    HttpClient client = null;
    private HttpClient getClient(){
        if(client!=null){
            return client;
        }
        HttpClient client = new HttpClient();
        client.getState().setCredentials(new AuthScope(requestIP, requestPort, null), new UsernamePasswordCredentials(user, password));
        client.getHttpConnectionManager().getParams().setConnectionTimeout(1000*60*5);
        client.getHttpConnectionManager().getParams().setSoTimeout(1000*60*5);
        this.client = client;
        return client;
    }

   /*传入刘德鹤的url 就可以得到json字符串*/
　 String  url = "http://1000.1992.2008.118:8080/adt/rest/data/getFillTabColumnsInfo?
   dbId=g5c5b886ed5c4de7826694bbb6025950&tableNm=yx_c_cust";

    /*只有这个方法有用传入url然后得到json*/
    @RequestMapping("restful")
    private void restfulReq(HttpServletRequest request, HttpServletResponse response) throws Exception{
        String url = request.getParameter("url");
        String res = "";
        HttpClient client = getClient();   //或者是直接new HttpClient
        PostMethod method = new PostMethod(url);  //改成post,以前是GetMethod
        method.getParams().setParameter(HttpMethodParams.RETRY_HANDLER, new DefaultHttpMethodRetryHandler());
        method.setDoAuthentication(true);
        try {
            int result = client.executeMethod(method); 
　　　　　　　　if(result != 200) {
                throw new Exception("访问Navigator失败，错误码：" + String.valueOf(result));
            }
  //        log.info("访问Navigator，获取数据完成！");
           res = method.getResponseBodyAsString();
            System.out.println(res);
        } catch (HttpException e) {
    //        log.error("访问Navigator失败！");
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally { //
　　　　  method.releaseConnection();
        }

        /*将res返回前台*/
        response.setContentType("application/json;charset=utf-8");
        PrintWriter out = null;
        try {
             out = response.getWriter();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }         

        out.print(res.toString());

        // return res; 必须注释掉，否则在ajax中的success中会报错
    }