Java利用HttpClient模拟POST表单操作应用及注意事项

package post;
import Java.io.IOException;
import org.apache.commons.httpclient.Header;
import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.HttpException;
import org.apache.commons.httpclient.HttpStatus;
import org.apache.commons.httpclient.NameValuePair;
import org.apache.commons.httpclient.methods.PostMethod;
public class PostHttp {
 /**
  * @param args
  */
 public static void main(String[] args) {
  // TODO Auto-generated method stub
  HttpClient httpClient = new HttpClient();
  String url = "http://193.167.13.21/setup.cgi";
  PostMethod postMethod = new PostMethod(url);
//   填入各个表单域的值
  NameValuePair[] data = {
    new NameValuePair("ID", "11"),
    new NameValuePair("mtg", "0"),
    new NameValuePair("haveCookie", "0"),
    new NameValuePair("backID", "30"),
    new NameValuePair("psw", "password")
  };
//   将表单的值放入postMethod中
  postMethod.setRequestBody(data);
//   执行postMethod
  int statusCode = 0;
  try {
   statusCode = httpClient.executeMethod(postMethod);
  } catch (HttpException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  } catch (IOException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
//   HttpClient对于要求接受后继服务的请求，象POST和PUT等不能自动处理转发
//   301或者302
  if (statusCode == HttpStatus.SC_MOVED_PERMANENTLY || statusCode == HttpStatus.SC_MOVED_TEMPORARILY)
  {
   //   从头中取出转向的地址
   Header locationHeader = postMethod.getResponseHeader("location");
   String location = null;
   if (locationHeader != null) {
    location = locationHeader.getValue();
    System.out.println("The page was redirected to:" + location);
   }
   else {
    System.err.println("Location field value is null.");
   }
   return;
  }
  else
  {
         System.out.println(postMethod.getStatusLine());
         String str = "";
         try {
               str = postMethod.getResponseBodyAsString();
         } catch (IOException e) {
               // TODO Auto-generated catch block
               e.printStackTrace();
         }       
         System.out.println(str);
  }
  postMethod.releaseConnection();
        return ;
 }
}