HttpClient实现文件下载

HttpClient实现文件下载：

用HttpClient实现文件下载需要满足：有一台web服务器，要下载的源文件需存放在web服务器的特定目录下。

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;

import org.apache.commons.httpclient.DefaultHttpMethodRetryHandler;
import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.HttpException;
import org.apache.commons.httpclient.HttpStatus;
import org.apache.commons.httpclient.methods.GetMethod;
import org.apache.commons.httpclient.params.HttpMethodParams;
import org.apache.log4j.Logger;

public class FileDownLoad {
private Logger logger = Logger.getLogger(FileDownLoad.class.getName());
public void downFile(String service_site,int service_port,String fileName,String localPath) {
     //构造HttpClient的实例
     HttpClient httpClient = new HttpClient();
     //创建GET方法的实例
     GetMethod getMethod = new GetMethod("http://"+service_site+":"+service_port+"/capaa/"+fileName);
     //使用系统提供的默认的恢复策略
     getMethod.getParams().setParameter(HttpMethodParams.RETRY_HANDLER,new DefaultHttpMethodRetryHandler());
     try
     {
         //执行getMethod
         int statusCode = httpClient.executeMethod(getMethod);
         if (statusCode != HttpStatus.SC_OK)