java编写Http服务器下载工具

import java.net.URL;
import java.net.URLConnection;
import java.io.File;
import java.io.InputStream;
import java.io.FileOutputStream;
import java.io.FileNotFoundException;
import java.io.IOException;

import org.apache.commons.io.FileUtils;

public class HttpUtil{
  private String httppath = "";

  public void setHttpPath(String httppath){
    this.httppath = httppath;
  }

  public String getHttpPath(){
    return this.httppath;
  }

  public HttpUtil(String httppath){
    this.httppath = httppath;
  }

  public InputStream getStream(String url){
    InputStream inStream = null;
    try{
      URL httpurl = new URL(url);
      URLConnection conn = httpurl.openConnection();
      inStream = conn.getInputStream();
    }catch (Exception e){
      e.printStackTrace();
      return null;
    }
    return inStream;
  }

  public int downLoad(String url,String localName ,int lines) throws FileNotFoundException, IOException{
    FileOutputStream fos = null;
    InputStream inStream = null;
    int ret = 0;
    try{
      URL httpurl = new URL(url);
      URLConnection conn = httpurl.openConnection();
      inStream = conn.getInputStream();
      fos = new FileOutputStream(localName);
      byte[] b = new byte[102400];
      int j = 0;
      while(inStream.read(b) != -1 && lines > 0){
        for(int i = j; i < b.length; i++){
          if(b[i] == '\n'){
            fos.write(b, j, i - j + 1);
            lines--;
            if(lines <= 0){
              break;
            }
            j = i + 1;
            continue;
          }
        }
      }
    }catch (Exception e){
      e.printStackTrace();
      ret = -1;
    }finally {
      fos.close();
      inStream.close();
      return ret;
    }
  }

  public static void main(String[] args){
    String httppath = "";
    int lines = 0;
    String localName = "";
    try{
      httppath = args[0];
      localName = args[1];
      lines = Integer.parseInt(args[2]);
    }catch (Exception e){
      e.printStackTrace();
      return;
    }
    try{
      HttpUtil hu = new HttpUtil(httppath);
      hu.downLoad(hu.getHttpPath(),localName ,lines);
    }catch (Exception e){
      e.printStackTrace();
    }
  }
}