详解JAVA中使用FTPClient工具类上传下载

详解java中使用ftpclient工具类上传下载

在java程序中，经常需要和ftp打交道，比如向ftp服务器上传文件、下载文件。本文简单介绍如何利用jakarta commons中的ftpclient（在commons-net包中）实现上传下载文件。

1、写一个javabean文件，描述ftp上传或下载的信息

实例代码：

public class ftpusebean { 
  private string host; 
  private integer port; 
  private string username; 
  private string password; 
  private string ftpseperator; 
  private string ftppath=""; 
  private int repeattime = 0;//连接ftp服务器的次数 
   
  public string gethost() { 
    return host; 
  } 
   
  public void sethost(string host) { 
    this.host = host; 
  } 
 
  public integer getport() { 
    return port; 
  } 
  public void setport(integer port) { 
    this.port = port; 
  } 
   
   
  public string getusername() { 
    return username; 
  } 
   
  public void setusername(string username) { 
    this.username = username; 
  } 
   
  public string getpassword() { 
    return password; 
  } 
   
  public void setpassword(string password) { 
    this.password = password; 
  } 
 
  public void setftpseperator(string ftpseperator) { 
    this.ftpseperator = ftpseperator; 
  } 
 
  public string getftpseperator() { 
    return ftpseperator; 
  } 
 
  public void setftppath(string ftppath) { 
    if(ftppath!=null) 
      this.ftppath = ftppath; 
  } 
 
  public string getftppath() { 
    return ftppath; 
  } 
 
  public void setrepeattime(int repeattime) { 
    if (repeattime > 0) 
      this.repeattime = repeattime; 
  } 
 
  public int getrepeattime() { 
    return repeattime; 
  } 
 
  /** 
   * take an example:<br> 
   * ftp://username:password@ip:port/ftppath/ 
   * @return 
   */ 
  public string getftpurl() { 
    stringbuffer buf = new stringbuffer(); 
    buf.append("ftp://"); 
    buf.append(getusername()); 
    buf.append(":"); 
    buf.append(getpassword()); 
    buf.append("@"); 
    buf.append(gethost()); 
    buf.append(":"); 
    buf.append(getport()); 
    buf.append("/"); 
    buf.append(getftppath()); 
      
    return buf.tostring(); 
  } 
} 

2、导入包commons-net-1.4.1.jar 

package com.util; 
 
import java.io.bufferedreader; 
import java.io.bytearrayoutputstream; 
import java.io.dataoutputstream; 
import java.io.file; 
import java.io.fileoutputstream; 
import java.io.ioexception; 
import java.io.inputstream; 
import java.io.inputstreamreader; 
import java.io.outputstream; 
import java.net.socketexception; 
import java.net.url; 
import java.net.urlconnection; 
 
import org.apache.commons.logging.log; 
import org.apache.commons.logging.logfactory; 
import org.apache.commons.net.ftp.ftp; 
import org.apache.commons.net.ftp.ftpclient; 
import org.apache.commons.net.ftp.ftpclientconfig; 
import org.apache.commons.net.ftp.ftpfile; 
 
import com.bean.ftpusebean; 
 
public class ftputil extends ftpclient { 
 
  private static log log = logfactory.getlog(ftputil.class); 
  private ftpusebean ftpusebean; 
  //获取目标路径下的文件属性信息，主要是获取文件的size 
  private ftpfile[] files; 
     
  public ftpusebean getftpusebean() { 
    return ftpusebean; 
  } 
 
 
  public ftputil(){ 
    super(); 
  } 
   
   
  public void setftpusebean(ftpusebean ftpusebean) { 
    this.ftpusebean = ftpusebean; 
  } 
   
  public boolean ftplogin() { 
    boolean islogined = false; 
    try { 
      log.debug("ftp login start ..."); 
      int repeattime = ftpusebean.getrepeattime(); 
      for (int i = 0; i < repeattime; i++) { 
        super.connect(ftpusebean.gethost(), ftpusebean.getport()); 
        islogined = super.login(ftpusebean.getusername(), ftpusebean.getpassword()); 
        if (islogined) 
          break; 
      } 
      if(islogined) 
        log.debug("ftp login successfully ..."); 
      else 
        log.debug("ftp login failed ..."); 
      return islogined; 
    } catch (socketexception e) { 
      log.error("", e); 
      return false; 
    } catch (ioexception e) { 
      log.error("", e); 
      return false; 
    } catch (runtimeexception e) { 
      log.error("", e); 
      return false; 
    } 
  } 
 
  public void setftptoutf8() throws ioexception { 
 
    ftpclientconfig conf = new ftpclientconfig(); 
    super.configure(conf); 
    super.setfiletype(ftp.image_file_type); 
    int reply = super.sendcommand("opts utf8 on"); 
    if (reply == 200) { // utf8 command 
      super.setcontrolencoding("utf-8"); 
    } 
 
  } 
 
  public void close() { 
    if (super.isconnected()) { 
      try { 
        super.logout(); 
        super.disconnect(); 
        log.debug("ftp logout ...."); 
      } catch (exception e) { 
        log.error(e.getmessage()); 
        throw new runtimeexception(e.tostring()); 
      } 
    } 
  } 
 
  public void uploadfiletoftpbyis(inputstream inputstream, string filename) throws ioexception { 
    super.storefile(ftpusebean.getftppath()+filename, inputstream); 
  } 
 
  public file downftpfile(string filename, string localfilename) throws ioexception { 
    file outfile = new file(localfilename); 
    outputstream ostream = null; 
    try { 
      ostream = new fileoutputstream(outfile); 
      super.retrievefile(ftpusebean.getftppath()+filename, ostream); 
      return outfile; 
    } finally { 
      if (ostream != null) 
        ostream.close(); 
    } 
  } 
 
 
  public ftpfile[] listftpfiles() throws ioexception { 
    return super.listfiles(ftpusebean.getftppath()); 
  } 
 
  public void deleteftpfiles(ftpfile[] ftpfiles) throws ioexception { 
    string path = ftpusebean.getftppath(); 
    for (ftpfile ff : ftpfiles) { 
      if (ff.isfile()) { 
        if (!super.deletefile(path + ff.getname())) 
          throw new runtimeexception("delete file" + ff.getname() + " is n't seccess"); 
      } 
    } 
  } 
 
  public void deleteftpfile(string filename) throws ioexception { 
    if (!super.deletefile(ftpusebean.getftppath() +filename)) 
      throw new runtimeexception("delete file" + ftpusebean.getftppath() +filename + " is n't seccess"); 
  } 
 
  public inputstream downftpfile(string filename) throws ioexception { 
    return super.retrievefilestream(ftpusebean.getftppath()+filename); 
  } 
 
  /** 
   * 
   * @return 
   * @return stringbuffer 
   * @description 下载ftp服务器上的文件,addr为带用户名和密码的url 
   */ 
  public stringbuffer downloadbufferbyurl(string addr) { 
    bufferedreader in = null; 
    try { 
      url url = new url(addr); 
      urlconnection conn = url.openconnection(); 
      in = new bufferedreader(new inputstreamreader(conn.getinputstream())); 
      string line; 
      stringbuffer ret = new stringbuffer(); 
      while ((line = in.readline()) != null) 
        ret.append(line); 
       
      return ret; 
    } catch (exception e) { 
      log.error(e); 
      return null; 
    } finally { 
      try { 
        if (null != in) 
          in.close(); 
      } catch (ioexception e) { 
        e.printstacktrace(); 
        log.error(e); 
      } 
    } 
  } 
 
  /** 
   * 
   * @return 
   * @return byte[] 
   * @description 下载ftp服务器上的文件,addr为带用户名和密码的url 
   */ 
  public byte[] downloadbytebyurl(string addr) { 
     
    ftpclient ftp = null; 
     
    try { 
       
      url url = new url(addr); 
       
      int port = url.getport()!=-1?url.getport():21; 
      log.info("host:"+url.gethost()); 
      log.info("port:"+port); 
      log.info("userinfo:"+url.getuserinfo()); 
      log.info("path:"+url.getpath()); 
       
      ftp = new ftpclient(); 
       
      ftp.setdatatimeout(30000); 
      ftp.setdefaulttimeout(30000); 
      ftp.setreaderthread(false); 
      ftp.connect(url.gethost(), port); 
      ftp.login(url.getuserinfo().split(":")[0], url.getuserinfo().split(":")[1]); 
      ftpclientconfig conf = new ftpclientconfig("unix");   
           ftp.configure(conf);  
      log.info(ftp.getreplystring()); 
       
      ftp.enterlocalpassivemode(); //ftp.enterremotepassivemode()  
      ftp.setfiletransfermode(ftp.stream_transfer_mode);  
 
      int reply = ftp.sendcommand("opts utf8 on");// try to 
       
      log.debug("alter to utf-8 encoding - reply:" + reply); 
      if (reply == 200) { // utf8 command 
        ftp.setcontrolencoding("utf-8"); 
      } 
      ftp.setfiletype(ftpclient.binary_file_type); 
 
      log.info(ftp.getreplystring()); 
       
      bytearrayoutputstream out=new bytearrayoutputstream(); 
           dataoutputstream o=new dataoutputstream(out); 
           string remotepath = url.getpath(); 
           /** 
           * fixed:if doen't remove the first "/" at the head of url, 
            * the file can't be retrieved. 
           */ 
           if(remotepath.indexof("/")==0) { 
             remotepath = url.getpath().replacefirst("/", ""); 
           } 
           ftp.retrievefile(remotepath, o);       
      byte[] ret = out.tobytearray(); 
      o.close(); 
       
      string filepath = url.getpath(); 
      ftp.changeworkingdirectory(filepath.substring(0,filepath.lastindexof("/"))); 
      files = ftp.listfiles(); 
       
      return ret; 
        } catch (exception ex) { 
      log.error("failed to download file from ["+addr+"]!"+ex); 
       } finally { 
      try { 
        if (null!=ftp) 
          ftp.disconnect(); 
      } catch (exception e) { 
        // 
      } 
    } 
    return null; 
//   stringbuffer buffer = downloadbufferbyurl(addr); 
//   return null == buffer ? null : buffer.tostring().getbytes(); 
  } 
   
   
   
   
  public ftpfile[] getfiles() { 
    return files; 
  } 
 
 
  public void setfiles(ftpfile[] files) { 
    this.files = files; 
  } 
 
 
// public static void getftpfilesize(string addr){ 
//    
//   ftpclient ftp = null; 
//    
//   try { 
//      
//     url url = new url(addr); 
//      
//     int port = url.getport()!=-1?url.getport():21; 
//     log.info("host:"+url.gethost()); 
//     log.info("port:"+port); 
//     log.info("userinfo:"+url.getuserinfo()); 
//     log.info("path:"+url.getpath()); 
//      
//     ftp = new ftpclient(); 
//      
//     ftp.setdatatimeout(30000); 
//     ftp.setdefaulttimeout(30000); 
//     ftp.setreaderthread(false); 
//     ftp.connect(url.gethost(), port); 
//     ftp.login(url.getuserinfo().split(":")[0], url.getuserinfo().split(":")[1]); 
//     ftpclientconfig conf = new ftpclientconfig("unix");   
//     ftp.configure(conf);  
//     log.info(ftp.getreplystring()); 
//      
//     ftp.enterlocalpassivemode(); //ftp.enterremotepassivemode()  
//     ftp.setfiletransfermode(ftp.stream_transfer_mode);  
// 
//     int reply = ftp.sendcommand("opts utf8 on");// try to 
//      
//     log.debug("alter to utf-8 encoding - reply:" + reply); 
//     if (reply == 200) { // utf8 command 
//       ftp.setcontrolencoding("utf-8"); 
//     } 
//     ftp.setfiletype(ftpclient.binary_file_type); 
//     ftp.changeworkingdirectory(url.getpath()); 
//     ftpfile[] files = ftp.listfiles(); 
//     for (ftpfile flie : files){ 
//       system.out.println(new string(flie.getname().getbytes("gbk"),"iso8859-1")); 
//       system.out.println(flie.getsize()); 
//     } 
//      
// 
//   } catch (exception ex) { 
//     log.error("failed to download file from ["+addr+"]!"+ex); 
//   } finally { 
//     try {<pre class="java" name="code">     if (null!=ftp) 
//     ftp.disconnect(); 
 //     } catch (exception e) { 
} 
} 
} 
}

以上就是java ftpclient工具类的上传和下载的实例详解，如有疑问请留言或者到本站社区交流讨论，感谢阅读，希望能帮助到大家，谢谢大家对本站的支持！