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java獲取ftp資源

發布時間: 2023-07-31 12:44:00

1. Java的ftp操作方法有哪幾種

FTP(File Transfer Protocol)是 Internet 上用來傳送文件的協議(文件傳輸協議)。它是為了我們能夠在 Internet 上互相傳送文件而制定的的文件傳送標准,規定了 Internet 上文件如何傳送。也就是說,通過 FTP 協議,我們就可以跟 Internet 上的 FTP 伺服器進行文件的上傳(Upload)或下載(Download)等動作。

和其他 Internet 應用一樣,FTP 也是依賴於客戶程序/伺服器關系的概念。在 Internet 上有一些網站,它們依照 FTP 協議提供服務,讓網友們進行文件的存取,這些網站就是 FTP 伺服器。網上的用戶要連上 FTP 伺服器,就要用到 FPT 的客戶端軟體,通常 Windows 都有「ftp」命令,這實際就是一個命令行的 FTP 客戶程序,另外常用的 FTP 客戶程序還有 CuteFTP、Ws_FTP、FTP Explorer等。

要連上 FTP 伺服器(即「登陸」),必須要有該 FTP 伺服器的帳號。如果是該伺服器主機的注冊客戶,你將會有一個 FTP 登陸帳號和密碼,就憑這個帳號密碼連上該伺服器。但 Internet 上有很大一部分 FTP 伺服器被稱為「匿名」(Anonymous)FTP 伺服器。這類伺服器的目的是向公眾提供文件拷貝服務,因此,不要求用戶事先在該伺服器進行登記注冊。

Anonymous(匿名文件傳輸)能夠使用戶與遠程主機建立連接並以匿名身份從遠程主機上拷貝文件,而不必是該遠程主機的注冊用戶。用戶使用特殊的用戶名「anonymous」和「guest」就可有限制地訪問遠程主機上公開的文件。現在許多系統要求用戶將Emai1地址作為口令,以便更好地對訪問進行跟綜。出於安全的目的,大部分匿名FTP主機一般只允許遠程用戶下載(download)文件,而不允許上載(upload)文件。也就是說,用戶只能從匿名FTP主機拷貝需要的文件而不能把文件拷貝到匿名FTP主機。另外,匿名FTP主機還採用了其他一些保護措施以保護自己的文件不至於被用戶修改和刪除,並防止計算機病毒的侵入。在具有圖形用戶界面的 WorldWild Web環境於1995年開始普及以前,匿名FTP一直是Internet上獲取信息資源的最主要方式,在Internet成千上萬的匿名PTP主機中存儲著無以計數的文件,這些文件包含了各種各樣的信息,數據和軟體。 人們只要知道特定信息資源的主機地址, 就可以用匿名FTP登錄獲取所需的信息資料。雖然目前使用WWW環境已取代匿名FTP成為最主要的信息查詢方式,但是匿名FTP仍是 Internet上傳輸分發軟體的一種基本方法

2. 如何用JAVA實現FTP訪問

在主函數中,完成伺服器埠的偵聽和服務線程的創建。我們利用一個靜態字元串變數initDir 來保存伺服器線程運行時所在的工作目錄。伺服器的初始工作目錄是由程序運行時用戶輸入的,預設為C盤的根目錄。
具體的代碼如下:
public class ftpServer extends Thread{
private Socket socketClient;
private int counter;
private static String initDir;
public static void main(String[] args){
if(args.length != 0) {
initDir = args[0];
}else{ initDir = "c:";}
int i = 1;
try{
System.out.println("ftp server started!");
//監聽21號埠
ServerSocket s = new ServerSocket(21);
for(;;){
//接受客戶端請求
Socket incoming = s.accept();
//創建服務線程
new ftpServer(incoming,i).start();
i++;
}
}catch(Exception e){}
}

3. java獲取ftp文件路徑怎麼寫

package com.weixin.util;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.io.RandomAccessFile;

import org.apache.commons.net.PrintCommandListener;
import org.apache.commons.net.ftp.FTP;
import org.apache.commons.net.ftp.FTPClient;
import org.apache.commons.net.ftp.FTPFile;
import org.apache.commons.net.ftp.FTPReply;

import com.weixin.constant.DownloadStatus;
import com.weixin.constant.UploadStatus;

/**
* 支持斷點續傳的FTP實用類
* @version 0.1 實現基本斷點上傳下載
* @version 0.2 實現上傳下載進度匯報
* @version 0.3 實現中文目錄創建及中文文件創建,添加對於中文的支持
*/
public class ContinueFTP {
public FTPClient ftpClient = new FTPClient();

public ContinueFTP(){
//設置將過程中使用到的命令輸出到控制台
this.ftpClient.addProtocolCommandListener(new PrintCommandListener(new PrintWriter(System.out)));
}

/**
* 連接到FTP伺服器
* @param hostname 主機名
* @param port 埠
* @param username 用戶名
* @param password 密碼
* @return 是否連接成功
* @throws IOException
*/
public boolean connect(String hostname,int port,String username,String password) throws IOException{
ftpClient.connect(hostname, port);
ftpClient.setControlEncoding("GBK");
if(FTPReply.isPositiveCompletion(ftpClient.getReplyCode())){
if(ftpClient.login(username, password)){
return true;
}
}
disconnect();
return false;
}

/**
* 從FTP伺服器上下載文件,支持斷點續傳,上傳百分比匯報
* @param remote 遠程文件路徑
* @param local 本地文件路徑
* @return 上傳的狀態
* @throws IOException
*/
public DownloadStatus download(String remote,String local) throws IOException{
//設置被動模式
ftpClient.enterLocalPassiveMode();
//設置以二進制方式傳輸
ftpClient.setFileType(FTP.BINARY_FILE_TYPE);
DownloadStatus result;

//檢查遠程文件是否存在
FTPFile[] files = ftpClient.listFiles(new String(remote.getBytes("GBK"),"iso-8859-1"));
if(files.length != 1){
System.out.println("遠程文件不存在");
return DownloadStatus.Remote_File_Noexist;
}

long lRemoteSize = files[0].getSize();
File f = new File(local);
//本地存在文件,進行斷點下載
if(f.exists()){
long localSize = f.length();
//判斷本地文件大小是否大於遠程文件大小
if(localSize >= lRemoteSize){
System.out.println("本地文件大於遠程文件,下載中止");
return DownloadStatus.Local_Bigger_Remote;
}

//進行斷點續傳,並記錄狀態
FileOutputStream out = new FileOutputStream(f,true);
ftpClient.setRestartOffset(localSize);
InputStream in = ftpClient.retrieveFileStream(new String(remote.getBytes("GBK"),"iso-8859-1"));
byte[] bytes = new byte[1024];
long step = lRemoteSize /100;
long process=localSize /step;
int c;
while((c = in.read(bytes))!= -1){
out.write(bytes,0,c);
localSize+=c;
long nowProcess = localSize /step;
if(nowProcess > process){
process = nowProcess;
if(process % 10 == 0)
System.out.println("下載進度:"+process);
//TODO 更新文件下載進度,值存放在process變數中
}
}
in.close();
out.close();
boolean isDo = ftpClient.completePendingCommand();
if(isDo){
result = DownloadStatus.Download_From_Break_Success;
}else {
result = DownloadStatus.Download_From_Break_Failed;
}
}else {
OutputStream out = new FileOutputStream(f);
InputStream in= ftpClient.retrieveFileStream(new String(remote.getBytes("GBK"),"iso-8859-1"));
byte[] bytes = new byte[1024];
long step = lRemoteSize /100;
long process=0;
long localSize = 0L;
int c;
while((c = in.read(bytes))!= -1){
out.write(bytes, 0, c);
localSize+=c;
long nowProcess = localSize /step;
if(nowProcess > process){
process = nowProcess;
if(process % 10 == 0)
System.out.println("下載進度:"+process);
//TODO 更新文件下載進度,值存放在process變數中
}
}
in.close();
out.close();
boolean upNewStatus = ftpClient.completePendingCommand();
if(upNewStatus){
result = DownloadStatus.Download_New_Success;
}else {
result = DownloadStatus.Download_New_Failed;
}
}
return result;
}

/**
* 上傳文件到FTP伺服器,支持斷點續傳
* @param local 本地文件名稱,絕對路徑
* @param remote 遠程文件路徑,使用/home/directory1/subdirectory/file.ext 按照Linux上的路徑指定方式,支持多級目錄嵌套,支持遞歸創建不存在的目錄結構
* @return 上傳結果
* @throws IOException
*/
public UploadStatus upload(String local,String remote) throws IOException{
//設置PassiveMode傳輸
ftpClient.enterLocalPassiveMode();
//設置以二進制流的方式傳輸
ftpClient.setFileType(FTP.BINARY_FILE_TYPE);
ftpClient.setControlEncoding("GBK");
UploadStatus result;
//對遠程目錄的處理
String remoteFileName = remote;
if(remote.contains("/")){
remoteFileName = remote.substring(remote.lastIndexOf("/")+1);
//創建伺服器遠程目錄結構,創建失敗直接返回
if(CreateDirecroty(remote, ftpClient)==UploadStatus.Create_Directory_Fail){
return UploadStatus.Create_Directory_Fail;
}
}

//檢查遠程是否存在文件
FTPFile[] files = ftpClient.listFiles(new String(remoteFileName.getBytes("GBK"),"iso-8859-1"));
if(files.length == 1){
long remoteSize = files[0].getSize();
File f = new File(local);
long localSize = f.length();
if(remoteSize==localSize){
return UploadStatus.File_Exits;
}else if(remoteSize > localSize){
return UploadStatus.Remote_Bigger_Local;
}

//嘗試移動文件內讀取指針,實現斷點續傳
result = uploadFile(remoteFileName, f, ftpClient, remoteSize);

//如果斷點續傳沒有成功,則刪除伺服器上文件,重新上傳
if(result == UploadStatus.Upload_From_Break_Failed){
if(!ftpClient.deleteFile(remoteFileName)){
return UploadStatus.Delete_Remote_Faild;
}
result = uploadFile(remoteFileName, f, ftpClient, 0);
}
}else {
result = uploadFile(remoteFileName, new File(local), ftpClient, 0);
}
return result;
}
/**
* 斷開與遠程伺服器的連接
* @throws IOException
*/
public void disconnect() throws IOException{
if(ftpClient.isConnected()){
ftpClient.disconnect();
}
}

/**
* 遞歸創建遠程伺服器目錄
* @param remote 遠程伺服器文件絕對路徑
* @param ftpClient FTPClient對象
* @return 目錄創建是否成功
* @throws IOException
*/
public UploadStatus CreateDirecroty(String remote,FTPClient ftpClient) throws IOException{
UploadStatus status = UploadStatus.Create_Directory_Success;
String directory = remote.substring(0,remote.lastIndexOf("/")+1);
if(!directory.equalsIgnoreCase("/")&&!ftpClient.changeWorkingDirectory(new String(directory.getBytes("GBK"),"iso-8859-1"))){
//如果遠程目錄不存在,則遞歸創建遠程伺服器目錄
int start=0;
int end = 0;
if(directory.startsWith("/")){
start = 1;
}else{
start = 0;
}
end = directory.indexOf("/",start);
while(true){
String subDirectory = new String(remote.substring(start,end).getBytes("GBK"),"iso-8859-1");
if(!ftpClient.changeWorkingDirectory(subDirectory)){
if(ftpClient.makeDirectory(subDirectory)){
ftpClient.changeWorkingDirectory(subDirectory);
}else {
System.out.println("創建目錄失敗");
return UploadStatus.Create_Directory_Fail;
}
}

start = end + 1;
end = directory.indexOf("/",start);

//檢查所有目錄是否創建完畢
if(end <= start){
break;
}
}
}
return status;
}

/**
* 上傳文件到伺服器,新上傳和斷點續傳
* @param remoteFile 遠程文件名,在上傳之前已經將伺服器工作目錄做了改變
* @param localFile 本地文件File句柄,絕對路徑
* @param processStep 需要顯示的處理進度步進值
* @param ftpClient FTPClient引用
* @return
* @throws IOException
*/
public UploadStatus uploadFile(String remoteFile,File localFile,FTPClient ftpClient,long remoteSize) throws IOException{
UploadStatus status;
//顯示進度的上傳
long step = localFile.length() / 100;
long process = 0;
long localreadbytes = 0L;
RandomAccessFile raf = new RandomAccessFile(localFile,"r");
OutputStream out = ftpClient.appendFileStream(new String(remoteFile.getBytes("GBK"),"iso-8859-1"));
//斷點續傳
if(remoteSize>0){
ftpClient.setRestartOffset(remoteSize);
process = remoteSize /step;
raf.seek(remoteSize);
localreadbytes = remoteSize;
}
byte[] bytes = new byte[1024];
int c;
while((c = raf.read(bytes))!= -1){
out.write(bytes,0,c);
localreadbytes+=c;
if(localreadbytes / step != process){
process = localreadbytes / step;
System.out.println("上傳進度:" + process);
//TODO 匯報上傳狀態
}
}
out.flush();
raf.close();
out.close();
boolean result =ftpClient.completePendingCommand();
if(remoteSize > 0){
status = result?UploadStatus.Upload_From_Break_Success:UploadStatus.Upload_From_Break_Failed;
}else {
status = result?UploadStatus.Upload_New_File_Success:UploadStatus.Upload_New_File_Failed;
}
return status;
}

public static void main(String[] args) {
ContinueFTP myFtp = new ContinueFTP();
try {
System.err.println(myFtp.connect("10.10.6.236", 21, "5", "jieyan"));
// myFtp.ftpClient.makeDirectory(new String("歌曲".getBytes("GBK"),"iso-8859-1"));
// myFtp.ftpClient.changeWorkingDirectory(new String("歌曲".getBytes("GBK"),"iso-8859-1"));
// myFtp.ftpClient.makeDirectory(new String("愛你等於愛自己".getBytes("GBK"),"iso-8859-1"));
// System.out.println(myFtp.upload("E:\\yw.flv", "/yw.flv",5));
// System.out.println(myFtp.upload("E:\\愛你等於愛自己.mp4","/愛你等於愛自己.mp4"));
//System.out.println(myFtp.download("/愛你等於愛自己.mp4", "E:\\愛你等於愛自己.mp4"));
myFtp.disconnect();
} catch (IOException e) {
System.out.println("連接FTP出錯:"+e.getMessage());
}
}
}

4. java 下載異地FTP中的zip文件

好像需要一個支持jar包把,把ftp4j的下載地址貼出來

5. 如何 用Java 實現 獲取FTP伺服器上的所有文件名,已知FTP的密碼,用戶名!遠程獲取!

public void ftpJdomFile(String dir) throws FileNotFoundException, IOException{
//創立根節點
// 下面這個方法是列出指定目錄下的所有文件和文件夾
List dirslist=Arrays.asList(new File(dir).listFiles());
for (Iterator i = dirslist.iterator(); i.hasNext();) {
// System.out.println(i.next()); // line 1
String s=i.next().toString();
if (new File(s).isFile()) {
System.out.println(s+"-文件");
}
if (new File(s).isDirectory()) {
System.out.println(s+"++++++++文件夾");
ftpJdomFile(s);
}

}

}

6. java如何獲取ftp制定目錄下所有文件集合(包括文件名稱)只要一個方法。

/**
* 取得相對於當前連接目錄的某個目錄下所有文件列表
*
* @param path
* @return
*/
public List getFileList(String path){
List list = new ArrayList();
DataInputStream dis;
try {
dis = new DataInputStream(ftpClient.nameList(this.path + path));
String filename = "";
while((filename = dis.readLine()) != null){
list.add(filename);
}
} catch (IOException e) {
e.printStackTrace();
}
return list;
}
我從這里拷來的 你不清楚看看裡面 http://hi..com/yuanhotel/item/000b6334894d11f42784f4da
滿意就採納 謝謝

7. java怎麼獲取ftp文件的路徑

public static void main(String[] args) {
// TODO Auto-generated method stub
// 創建File對象
File file = new File("d:\\");
// 使用遞歸方法做
dg(file);
}

private static void dg(File fl) {
// TODO Auto-generated method stub
// 創建file數組用來存儲數據
File[] filArr = fl.listFiles();
// 判斷FiLe數組不能為空
if (filArr != null) {
// 使用for遍歷
for (File f : filArr) {
// 如果是文件夾 就遞歸
if (f.isDirectory()) {
// 遞歸
dg(f);
} else if (f.isFile()) {

System.out.println(f.getAbsolutePath());
}
}
}
}

8. 如何用java連接到ftp上

現在已經封裝好了的方法,不需要任何其他知識即可連接的。只需要知道ftp登錄用戶名、密碼、埠、存儲路徑即可。
package zn.ccfccb.util;

import hkrt.b2b.view.util.Log;
import hkrt.b2b.view.util.ViewUtil;
import java.io.ByteArrayOutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;

import org.apache.commons.net.ftp.FTPClient;
import org.apache.commons.net.ftp.FTPFile;

public class CCFCCBFTP {

/**
* 上傳文件
*
* @param fileName
* @param plainFilePath 明文文件路徑路徑
* @param filepath
* @return
* @throws Exception
*/
public static String fileUploadByFtp(String plainFilePath, String fileName, String filepath) throws Exception {
FileInputStream fis = null;
ByteArrayOutputStream bos = null;
FTPClient ftpClient = new FTPClient();
String bl = "false";
try {
fis = new FileInputStream(plainFilePath);
bos = new ByteArrayOutputStream(fis.available());
byte[] buffer = new byte[1024];
int count = 0;
while ((count = fis.read(buffer)) != -1) {
bos.write(buffer, 0, count);
}
bos.flush();
Log.info("加密上傳文件開始");
Log.info("連接遠程上傳伺服器"+CCFCCBUtil.CCFCCBHOSTNAME+":"+22);
ftpClient.connect(CCFCCBUtil.CCFCCBHOSTNAME, 22);
ftpClient.login(CCFCCBUtil.CCFCCBLOGINNAME, CCFCCBUtil.CCFCCBLOGINPASSWORD);
// Log.info("連接遠程上傳伺服器"+"192.168.54.106:"+2021);
// ftpClient.connect("192.168.54.106", 2021);
// ftpClient.login("hkrt-CCFCCBHK", "3OLJheziiKnkVcu7Sigz");
FTPFile[] fs;
fs = ftpClient.listFiles();
for (FTPFile ff : fs) {
if (ff.getName().equals(filepath)) {
bl="true";
ftpClient.changeWorkingDirectory("/"+filepath+"");
}
}
Log.info("檢查文件路徑是否存在:/"+filepath);
if("false".equals(bl)){
ViewUtil.dataSEErrorPerformedCommon( "查詢文件路徑不存在:"+"/"+filepath);
return bl;
}
ftpClient.setBufferSize(1024);
ftpClient.setControlEncoding("GBK");
// 設置文件類型(二進制)
ftpClient.setFileType(FTPClient.BINARY_FILE_TYPE);
ftpClient.storeFile(fileName, fis);
Log.info("上傳文件成功:"+fileName+"。文件保存路徑:"+"/"+filepath+"/");
return bl;
} catch (Exception e) {
throw e;
} finally {
if (fis != null) {
try {
fis.close();
} catch (Exception e) {
Log.info(e.getLocalizedMessage(), e);
}
}
if (bos != null) {
try {
bos.close();
} catch (Exception e) {
Log.info(e.getLocalizedMessage(), e);
}
}
}

}

/**
*下載並解壓文件
*
* @param localFilePath
* @param fileName
* @param routeFilepath
* @return
* @throws Exception
*/
public static String fileDownloadByFtp(String localFilePath, String fileName,String routeFilepath) throws Exception {
FileInputStream fis = null;
ByteArrayOutputStream bos = null;
FileOutputStream fos = null;
FTPClient ftpClient = new FTPClient();
String SFP = System.getProperty("file.separator");
String bl = "false";
try {
Log.info("下載並解密文件開始");
Log.info("連接遠程下載伺服器"+CCFCCBUtil.CCFCCBHOSTNAME+":"+22);
ftpClient.connect(CCFCCBUtil.CCFCCBHOSTNAME, 22);
ftpClient.login(CCFCCBUtil.CCFCCBLOGINNAME, CCFCCBUtil.CCFCCBLOGINPASSWORD);
// ftpClient.connect(CMBCUtil.CMBCHOSTNAME, 2021);
// ftpClient.login(CMBCUtil.CMBCLOGINNAME, CMBCUtil.CMBCLOGINPASSWORD);
FTPFile[] fs;

ftpClient.makeDirectory(routeFilepath);
ftpClient.changeWorkingDirectory(routeFilepath);
bl = "false";
fs = ftpClient.listFiles();
for (FTPFile ff : fs) {
if (ff.getName().equals(fileName)) {
bl = "true";
Log.info("下載文件開始。");
ftpClient.setBufferSize(1024);
// 設置文件類型(二進制)
ftpClient.setFileType(FTPClient.BINARY_FILE_TYPE);
InputStream is = ftpClient.retrieveFileStream(fileName);
bos = new ByteArrayOutputStream(is.available());
byte[] buffer = new byte[1024];
int count = 0;
while ((count = is.read(buffer)) != -1) {
bos.write(buffer, 0, count);
}
bos.flush();
fos = new FileOutputStream(localFilePath+SFP+fileName);
fos.write(bos.toByteArray());
Log.info("下載文件結束:"+localFilePath);
}
}
Log.info("檢查文件是否存:"+fileName+" "+bl);
if("false".equals(bl)){
ViewUtil.dataSEErrorPerformedCommon("查詢無結果,請稍後再查詢。");
return bl;
}
return bl;
} catch (Exception e) {
throw e;
} finally {
if (fis != null) {
try {
fis.close();
} catch (Exception e) {
Log.info(e.getLocalizedMessage(), e);
}
}
if (bos != null) {
try {
bos.close();
} catch (Exception e) {
Log.info(e.getLocalizedMessage(), e);
}
}
if (fos != null) {
try {
fos.close();
} catch (Exception e) {
Log.info(e.getLocalizedMessage(), e);
}

9. java在瀏覽器上獲取FTP讀文件路徑

問一下,你是想做ftp上傳下載么?

  1. 首先你需要安裝一個ftp服務端程序,啟動起來,然後下載一個ftp客戶端程序,測試能不能連接,首先這一塊兒需要測試通過。

  2. 代碼ftp上傳下載

2.1 上傳代碼:

import java.io.File;

import java.io.FileInputStream;

import org.apache.commons.net.ftp.FTPClient;

import org.apache.commons.net.ftp.FTPReply;

public class test {

private FTPClient ftp;

/**

*

* @param path 上傳到ftp伺服器哪個路徑下

* @param addr 地址

* @param port 埠號

* @param username 用戶名

* @param password 密碼

* @return

* @throws Exception

*/

private boolean connect(String path,String addr,int port,String username,String password) throws Exception {

boolean result = false;

ftp = new FTPClient();

int reply;

ftp.connect(addr,port);

ftp.login(username,password);

ftp.setFileType(FTPClient.BINARY_FILE_TYPE);

reply = ftp.getReplyCode();

if (!FTPReply.isPositiveCompletion(reply)) {

ftp.disconnect();

return result;

}

ftp.changeWorkingDirectory(path);

result = true;

return result;

}

/**

*

* @param file 上傳的文件或文件夾

* @throws Exception

*/

private void upload(File file) throws Exception{

if(file.isDirectory()){

ftp.makeDirectory(file.getName());

ftp.changeWorkingDirectory(file.getName());

String[] files = file.list();

for (int i = 0; i < files.length; i++) {

File file1 = new File(file.getPath()+"\"+files[i] );

if(file1.isDirectory()){

upload(file1);

ftp.changeToParentDirectory();

}else{

File file2 = new File(file.getPath()+"\"+files[i]);

FileInputStream input = new FileInputStream(file2);

ftp.storeFile(file2.getName(), input);

input.close();

}

}

}else{

File file2 = new File(file.getPath());

FileInputStream input = new FileInputStream(file2);

ftp.storeFile(file2.getName(), input);

input.close();

}

}

public static void main(String[] args) throws Exception{

test t = new test();

t.connect("", "localhost", 21, "yhh", "yhhazr");

File file = new File("e:\uploadify");

t.upload(file);

}

}

2.2 下載代碼

這里沒有用到filter,如果用filter就可以過濾想要的文件。

public class Ftp {

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
Ftp ftp = new Ftp();
String hostname = "www.strawberry.com";
Integer port = 21;
String username = "username";
String password = "password";
String remote = "/c.txt";
String local = "/home/tin/LeonChen/FTP/";
try {
ftp.connect(hostname, port, username, password);
System.out.println("接收狀態:"+ftp.download(remote, local));
ftp.disconnect();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

private FTPClient ftpClient = new FTPClient();

/*
* * 連接到FTP伺服器
* * @param hostname 主機名
* * @param port 埠
* * @param username 用戶名
* * @param password 密碼
* * @return 是否連接成功
* * @throws IOException
*/
private boolean connect(String hostname, int port, String username,
String password) throws IOException {
ftpClient.connect(hostname, port);
ftpClient.setControlEncoding("UTF-8");
if (FTPReply.isPositiveCompletion(ftpClient.getReplyCode())) {
if (ftpClient.login(username, password)) {
return true;
}
}
disconnect();
return false;
}

/*
* 從FTP伺服器上下載文件,支持斷點續傳,上傳百分比匯報
*
* @param remote 遠程文件路徑
*
* @param local 本地文件路徑
*
* @return 上傳的狀態
*
* @throws IOException
*/
public DownloadStatus download(String remote, String local)
throws IOException {
// 設置被動模式
ftpClient.enterLocalPassiveMode();
// 設置以二進制方式傳輸
ftpClient.setFileType(FTP.BINARY_FILE_TYPE);
DownloadStatus result;
// 檢查遠程文件是否存在
FTPFile[] files = ftpClient.listFiles(new String(remote
.getBytes("UTF-8"), "iso-8859-1"));
if (files.length != 1) {
System.out.println("遠程文件不存在");
return DownloadStatus.Remote_File_Noexist;
}
long lRemoteSize = files[0].getSize();
String fildName = files[0].getName();
// 本地存在文件,進行斷點下載
File f = new File(local+fildName);
if (f.exists()) {
long localSize = f.length();
if (localSize >= lRemoteSize) {
System.out.println("本地文件大於遠程文件,下載中止");
return DownloadStatus.Local_Bigger_Remote;
}

// 進行斷點續傳,並記錄狀態
FileOutputStream out = new FileOutputStream(f, true);
ftpClient.setRestartOffset(localSize);
InputStream in = ftpClient.retrieveFileStream(new String(remote.getBytes("UTF-8"), "iso-8859-1"));
byte[] bytes = new byte[1024];
long step = lRemoteSize / 100;
long process = localSize / step;
int c;
while ((c = in.read(bytes)) != -1) {
out.write(bytes, 0, c);
localSize += c;
long nowProcess = localSize / step;
if (nowProcess > process) {
process = nowProcess;
if (process % 10 == 0)
System.out.println("下載進度:" + process);
// TODO 更新文件下載進度,值存放在process變數中
}
}
in.close();
out.close();
boolean isDo = ftpClient.completePendingCommand();
if (isDo) {
result = DownloadStatus.Download_From_Break_Success;
} else {
result = DownloadStatus.Download_From_Break_Failed;
}
} else {
OutputStream out = new FileOutputStream(f);
InputStream in = ftpClient.retrieveFileStream(new String(remote.getBytes("UTF-8"), "iso-8859-1"));
byte[] bytes = new byte[1024];
long step = lRemoteSize / 100;
long process = 0;
long localSize = 0L;
int c;
while ((c = in.read(bytes)) != -1) {
out.write(bytes, 0, c);
localSize += c;
long nowProcess = localSize / step;
if (nowProcess > process) {
process = nowProcess;
if (process % 10 == 0)
System.out.println("下載進度:" + process);
// TODO 更新文件下載進度,值存放在process變數中
}
}
in.close();
out.close();
boolean upNewStatus = ftpClient.completePendingCommand();
if (upNewStatus) {
result = DownloadStatus.Download_New_Success;
} else {
result = DownloadStatus.Download_New_Failed;
}
}
return result;
}

private void disconnect() throws IOException {
if (ftpClient.isConnected()) {
ftpClient.disconnect();
}
}

}