Ⅰ 请问一下,java中有没直接判断ftp上文件夹下是否存在某文件的方法通过遍历文件夹的方式判断太耗内存了
第一个种方法 :
org.apache.commons.net.ftp.* 看这个目录下是否有你要的方法
第二种方法:
package com.soft4j.log4j;
import java.io.IOException;
import sun.net.ftp.FtpClient;
public class FtpTest
{
static String middle_ftpServer = "10.103.2.250";
static String middle_user = "ora9iftp";
static String middle_password = "ftp";
static String middle_dir = "/image/NWKPHOTO/Middle/2009/3";
public static void main(String[] args)
{
FtpClient ftpClient = new FtpClient();
try
{
ftpClient.openServer(middle_ftpServer);
ftpClient.login(middle_user, middle_password);
FtpTest ft = new FtpTest();
ft.isDirExist(ftpClient, middle_dir);
} catch (IOException e)
{
e.printStackTrace();
}
}
/** 判断Ftp目录是否存在,如果不存在则创建目录 */
public void isDirExist(FtpClient ftpClient, String dir)
{
try
{
ftpClient.cd(dir); //想不到什么好办法来判断目录是否存在,只能用异常了(比较笨).请知道的告诉我一声`
} catch (IOException e1)
{
ftpClient.sendServer("MKD " + dir + "\r\n");
try
{
ftpClient.readServerResponse();
} catch (IOException e)
{
e.printStackTrace();
}
}
}
}
Ⅱ 求用java写一个ftp服务器客户端程序。
import java.io.*;
import java.net.*;public class ftpServer extends Thread{ public static void main(String args[]){
String initDir;
initDir = "D:/Ftp";
ServerSocket server;
Socket socket;
String s;
String user;
String password;
user = "root";
password = "123456";
try{
System.out.println("MYFTP服务器启动....");
System.out.println("正在等待连接....");
//监听21号端口
server = new ServerSocket(21);
socket = server.accept();
System.out.println("连接成功");
System.out.println("**********************************");
System.out.println("");
InputStream in =socket.getInputStream();
OutputStream out = socket.getOutputStream();
DataInputStream din = new DataInputStream(in);
DataOutputStream dout=new DataOutputStream(out);
System.out.println("请等待验证客户信息....");
while(true){
s = din.readUTF();
if(s.trim().equals("LOGIN "+user)){
s = "请输入密码:";
dout.writeUTF(s);
s = din.readUTF();
if(s.trim().equals(password)){
s = "连接成功。";
dout.writeUTF(s);
break;
}
else{s ="密码错误,请重新输入用户名:";<br> dout.writeUTF(s);<br> <br> }
}
else{
s = "您输入的命令不正确或此用户不存在,请重新输入:";
dout.writeUTF(s);
}
}
System.out.println("验证客户信息完毕...."); while(true){
System.out.println("");
System.out.println("");
s = din.readUTF();
if(s.trim().equals("DIR")){
String output = "";
File file = new File(initDir);
String[] dirStructure = new String[10];
dirStructure= file.list();
for(int i=0;i<dirStructure.length;i++){
output +=dirStructure[i]+"\n";
}
s=output;
dout.writeUTF(s);
}
else if(s.startsWith("GET")){
s = s.substring(3);
s = s.trim();
File file = new File(initDir);
String[] dirStructure = new String[10];
dirStructure= file.list();
String e= s;
int i=0;
s ="不存在";
while(true){
if(e.equals(dirStructure[i])){
s="存在";
dout.writeUTF(s);
RandomAccessFile outFile = new RandomAccessFile(initDir+"/"+e,"r");
byte byteBuffer[]= new byte[1024];
int amount;
while((amount = outFile.read(byteBuffer)) != -1){
dout.write(byteBuffer, 0, amount);break;
}break;
}
else if(i<dirStructure.length-1){
i++;
}
else{
dout.writeUTF(s);
break;
}
}
}
else if(s.startsWith("PUT")){
s = s.substring(3);
s = s.trim();
RandomAccessFile inFile = new RandomAccessFile(initDir+"/"+s,"rw");
byte byteBuffer[] = new byte[1024];
int amount;
while((amount =din.read(byteBuffer) )!= -1){
inFile.write(byteBuffer, 0, amount);break;
}
}
else if(s.trim().equals("BYE"))break;
else{
s = "您输入的命令不正确或此用户不存在,请重新输入:";
dout.writeUTF(s);
}
}
din.close();
dout.close();
in.close();
out.close();
socket.close();
}
catch(Exception e){
System.out.println("MYFTP关闭!"+e);
}
}}
Ⅲ ftp获取不到文件目录,但是登录是成功的。 java
不知道你用的哪个.jar?commons-net.jar包中可以用 ftpClient.listFiles(pathName);返回值是个FTPFile[],jdk里也有访问ftp的类,用过感觉不太好用,好像中文名称的文件会出现乱码,不太记得怎么用了.如果还取不到ftpClient.changeWorkingDirectory(path);可以试试这个,在查下面的目录
Ⅳ 用java实现FTP需要导入什么包,导入哪里呢,能不能改个包
有二个种FTP方式:ftp和sftp
ftp的包:commons-net-3.3.jar
sftp包:com.jcraft.jsch_0.1.31.jar
Ⅳ java中如何判断ftp服务器上的某个目录是否存在
ftpClient.makeDirectory(目录地址); 返回结果true或false
返回true证明创建成功,即在执行创建命令前ftp上不存在此目录
返回false证明创建失败,即ftp上已存在此目录
Ⅵ 用JAVA编写一个程序实现输出我的电脑上建立的FTP服务器根目录下的所有文件名
使用File类中方法就可以实现
File[] listFiles() 返回目录下所有的文件
File file=new File("你的ftp的根路径");
File files[]=file.listFiles();
for(int i=0;i<files.length;i++){
System.out.println(files[i].getName() );
}
如果要获取所有的文件和文件夹可以使用String[] list()方法。返回的是String类型的数组,其中所有文件和文件夹的相对路径表示。
补充---
如果那样的话那么就需要在你的ftp服务器上做一个socket服务端,你通过一个客户端连接上去。然后服务器端将获取的文件列表数组传递给你,就可以了。如果想直接获取别人的机器的文件列表是很难的,基本上是不可能的,当然是出于安全的考虑
Ⅶ 用java怎么获取ftp上的文件
public class FtpClientUtil {
FtpClient ftpClient;
private String server;
private int port;
private String userName;
private String userPassword;
public FtpClientUtil(String server,int port,String userName,String userPassword)
{
this.server=server;
this.port=port;
this.userName=userName;
this.userPassword=userPassword;
}
/**
* 链接到服务器
* @return
*/
public boolean open()
{
if(ftpClient!=null&&ftpClient.serverIsOpen())
return true;
try
{
ftpClient= new FtpClient();
ftpClient.openServer(server,port);
ftpClient.login(userName, userPassword);
ftpClient.binary();
return true;
}
catch(Exception e)
{
e.printStackTrace();
ftpClient=null;
return false;
}
}
public boolean cd(String dir){
boolean f = false;
try {
ftpClient.cd(dir);
} catch (IOException e) {
Logs.error(e.toString());
return f;
}
return true;
}
/**
* 上传文件到铅启FTP服务器
* @param localPathAndFileName 本地文件目录和文件名
* @param ftpFileName 上传后的文件名
* @param ftpDirectory FTP目录如:/烂激袭path1/pathb2/,如果目录不存在回自动创建目录
* @throws Exception
*/
public boolean upload(String localDirectoryAndFileName,String ftpFileName,String ftpDirectory)throws Exception {
if(!open())
return false;
FileInputStream is=null;
TelnetOutputStream os=null;
try
{
char ch = ' ';
if (ftpDirectory.length() >饥兄 0)
ch = ftpDirectory.charAt(ftpDirectory.length() - 1);
for (; ch == '/' || ch == '\\'; ch = ftpDirectory.charAt(ftpDirectory.length() - 1))
ftpDirectory = ftpDirectory.substring(0, ftpDirectory.length() - 1);
int slashIndex = ftpDirectory.indexOf(47);
int backslashIndex = ftpDirectory.indexOf(92);
int index = slashIndex;
String dirall = ftpDirectory;
if (backslashIndex != -1 && (index == -1 || index > backslashIndex))
index = backslashIndex;
String directory = "";
while (index != -1) {
if (index > 0) {
String dir = dirall.substring(0, index);
directory = directory + "/" + dir;
ftpClient.sendServer("XMKD " + directory + "\r\n");
ftpClient.readServerResponse();
}
dirall = dirall.substring(index + 1);
slashIndex = dirall.indexOf(47);
backslashIndex = dirall.indexOf(92);
index = slashIndex;
if (backslashIndex != -1 && (index == -1 || index > backslashIndex))
index = backslashIndex;
}
ftpClient.sendServer("XMKD " + ftpDirectory + "\r\n");
ftpClient.readServerResponse();
os = ftpClient.put(ftpDirectory + "/"
+ ftpFileName);
File file_in = new File(localDirectoryAndFileName);
is = new FileInputStream(file_in);
byte bytes[] = new byte[1024];
int i;
while ((i = is.read(bytes)) != -1)
os.write(bytes, 0, i);
//清理垃圾
return true;
}
catch(Exception e)
{
e.printStackTrace();
return false;
}
finally
{
if (is != null)
is.close();
if (os != null)
os.close();
}
}
/**
* 从FTP服务器上下载文件并返回下载文件长度
* @param ftpDirectoryAndFileName
* @param localDirectoryAndFileName
* @return
* @throws Exception
*/
public long download(String ftpDirectoryAndFileName,String localDirectoryAndFileName)throws Exception
{
long result = 0;
if(!open())
return result;
TelnetInputStream is = null;
FileOutputStream os = null;
try
{
is = ftpClient.get(ftpDirectoryAndFileName);
java.io.File outfile = new java.io.File(localDirectoryAndFileName);
os = new FileOutputStream(outfile);
byte[] bytes = new byte[1024];
int c;
while ((c = is.read(bytes)) != -1)
{
os.write(bytes, 0, c);
result = result + c;
}
}
catch (Exception e)
{
throw e;
}
finally
{
if (is != null)
is.close();
if (os != null)
os.close();
}
return result;
}
/**
* 返回FTP目录下的文件列表
* @param ftpDirectory
* @return
*/
public List<String> getFileNameList(String ftpDirectory)
{
List<String> list = new ArrayList<String>();
if(!open())
return list;
try
{
DataInputStream dis = new DataInputStream(ftpClient.nameList(ftpDirectory));
String filename = "";
while((filename=dis.readLine())!=null)
{
list.add(filename);
}
} catch (Exception e)
{
e.printStackTrace();
}
return list;
}
/**
* 删除FTP上的文件
* @param ftpDirAndFileName
*/
public boolean deleteFile(String ftpDirAndFileName)
{
if(!open())
return false;
ftpClient.sendServer("DELE "+ftpDirAndFileName+"\r\n");
return true;
}
/**
* 删除FTP目录
* @param ftpDirectory
*/
public boolean deleteDirectory(String ftpDirectory)
{
if(!open())
return false;
ftpClient.sendServer("XRMD "+ftpDirectory+"\r\n");
return true;
}
/**
* 关闭链接
*/
public void close()
{
try
{
if(ftpClient!=null&&ftpClient.serverIsOpen())
ftpClient.closeServer();
}catch(Exception e)
{
}
}
}望采纳,谢谢。
Ⅷ 如何 用Java 实现 获取FTP服务器上的所有文件名,已知FTP的密码,用户名!远程获取!
public void ftpJdomFile(String dir) throws FileNotFoundException, IOException{
//创立根节点
// 下面这个方法是列出指定目录下的所有文件和文件夹
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+"++++++++文件夹");
ftpJdomFile(s);
}
}
}
Ⅸ java 怎么从ftp获取文件路径
拿去用吧。
packagecom.weixin.util;
importjava.io.File;
importjava.io.FileOutputStream;
importjava.io.IOException;
importjava.io.InputStream;
importjava.io.OutputStream;
importjava.io.PrintWriter;
importjava.io.RandomAccessFile;
importorg.apache.commons.net.PrintCommandListener;
importorg.apache.commons.net.ftp.FTP;
importorg.apache.commons.net.ftp.FTPClient;
importorg.apache.commons.net.ftp.FTPFile;
importorg.apache.commons.net.ftp.FTPReply;
importcom.weixin.constant.DownloadStatus;
importcom.weixin.constant.UploadStatus;
/**
*支持断点续传的FTP实用类
*@version0.1实现基本断点上传下载
*@version0.2实现上传下载进度汇报
*@version0.3实现中文目录创建及中文文件创建,添加对于中文的支持
*/
publicclassContinueFTP{
publicFTPClientftpClient=newFTPClient();
publicContinueFTP(){
//设置将过程中使用到的命令输出到控制台
this.ftpClient.addProtocolCommandListener(newPrintCommandListener(newPrintWriter(System.out)));
}
/**
*连接到FTP服务器
*@paramhostname主机名
*@paramport端口
*@paramusername用户名
*@parampassword密码
*@return是否连接成功
*@throwsIOException
*/
publicbooleanconnect(Stringhostname,intport,Stringusername,Stringpassword)throwsIOException{
ftpClient.connect(hostname,port);
ftpClient.setControlEncoding("GBK");
if(FTPReply.isPositiveCompletion(ftpClient.getReplyCode())){
if(ftpClient.login(username,password)){
returntrue;
}
}
disconnect();
returnfalse;
}
/**
*从FTP服务器上下载文件,支持断点续传,上传百分比汇报
*@paramremote远程文件路径
*@paramlocal本地文件路径
*@return上传的状态
*@throwsIOException
*/
publicDownloadStatusdownload(Stringremote,Stringlocal)throwsIOException{
//设置被动模式
ftpClient.enterLocalPassiveMode();
//设置以二进制方式传输
ftpClient.setFileType(FTP.BINARY_FILE_TYPE);
DownloadStatusresult;
//检查远程文件是否存在
FTPFile[]files=ftpClient.listFiles(newString(remote.getBytes("GBK"),"iso-8859-1"));
if(files.length!=1){
System.out.println("远程文件不存在");
returnDownloadStatus.Remote_File_Noexist;
}
longlRemoteSize=files[0].getSize();
Filef=newFile(local);
//本地存在文件,进行断点下载
if(f.exists()){
longlocalSize=f.length();
//判断本地文件大小是否大于远程文件大小
if(localSize>=lRemoteSize){
System.out.println("本地文件大于远程文件,下载中止");
returnDownloadStatus.Local_Bigger_Remote;
}
//进行断点续传,并记录状态
FileOutputStreamout=newFileOutputStream(f,true);
ftpClient.setRestartOffset(localSize);
InputStreamin=ftpClient.retrieveFileStream(newString(remote.getBytes("GBK"),"iso-8859-1"));
byte[]bytes=newbyte[1024];
longstep=lRemoteSize/100;
longprocess=localSize/step;
intc;
while((c=in.read(bytes))!=-1){
out.write(bytes,0,c);
localSize+=c;
longnowProcess=localSize/step;
if(nowProcess>process){
process=nowProcess;
if(process%10==0)
System.out.println("下载进度:"+process);
//TODO更新文件下载进度,值存放在process变量中
}
}
in.close();
out.close();
booleanisDo=ftpClient.completePendingCommand();
if(isDo){
result=DownloadStatus.Download_From_Break_Success;
}else{
result=DownloadStatus.Download_From_Break_Failed;
}
}else{
OutputStreamout=newFileOutputStream(f);
InputStreamin=ftpClient.retrieveFileStream(newString(remote.getBytes("GBK"),"iso-8859-1"));
byte[]bytes=newbyte[1024];
longstep=lRemoteSize/100;
longprocess=0;
longlocalSize=0L;
intc;
while((c=in.read(bytes))!=-1){
out.write(bytes,0,c);
localSize+=c;
longnowProcess=localSize/step;
if(nowProcess>process){
process=nowProcess;
if(process%10==0)
System.out.println("下载进度:"+process);
//TODO更新文件下载进度,值存放在process变量中
}
}
in.close();
out.close();
booleanupNewStatus=ftpClient.completePendingCommand();
if(upNewStatus){
result=DownloadStatus.Download_New_Success;
}else{
result=DownloadStatus.Download_New_Failed;
}
}
returnresult;
}
/**
*上传文件到FTP服务器,支持断点续传
*@paramlocal本地文件名称,绝对路径
*@paramremote远程文件路径,使用/home/directory1/subdirectory/file.ext按照Linux上的路径指定方式,支持多级目录嵌套,支持递归创建不存在的目录结构
*@return上传结果
*@throwsIOException
*/
publicUploadStatusupload(Stringlocal,Stringremote)throwsIOException{
//设置PassiveMode传输
ftpClient.enterLocalPassiveMode();
//设置以二进制流的方式传输
ftpClient.setFileType(FTP.BINARY_FILE_TYPE);
ftpClient.setControlEncoding("GBK");
UploadStatusresult;
//对远程目录的处理
StringremoteFileName=remote;
if(remote.contains("/")){
remoteFileName=remote.substring(remote.lastIndexOf("/")+1);
//创建服务器远程目录结构,创建失败直接返回
if(CreateDirecroty(remote,ftpClient)==UploadStatus.Create_Directory_Fail){
returnUploadStatus.Create_Directory_Fail;
}
}
//检查远程是否存在文件
FTPFile[]files=ftpClient.listFiles(newString(remoteFileName.getBytes("GBK"),"iso-8859-1"));
if(files.length==1){
longremoteSize=files[0].getSize();
Filef=newFile(local);
longlocalSize=f.length();
if(remoteSize==localSize){
returnUploadStatus.File_Exits;
}elseif(remoteSize>localSize){
returnUploadStatus.Remote_Bigger_Local;
}
//尝试移动文件内读取指针,实现断点续传
result=uploadFile(remoteFileName,f,ftpClient,remoteSize);
//如果断点续传没有成功,则删除服务器上文件,重新上传
if(result==UploadStatus.Upload_From_Break_Failed){
if(!ftpClient.deleteFile(remoteFileName)){
returnUploadStatus.Delete_Remote_Faild;
}
result=uploadFile(remoteFileName,f,ftpClient,0);
}
}else{
result=uploadFile(remoteFileName,newFile(local),ftpClient,0);
}
returnresult;
}
/**
*断开与远程服务器的连接
*@throwsIOException
*/
publicvoiddisconnect()throwsIOException{
if(ftpClient.isConnected()){
ftpClient.disconnect();
}
}
/**
*递归创建远程服务器目录
*@paramremote远程服务器文件绝对路径
*@paramftpClientFTPClient对象
*@return目录创建是否成功
*@throwsIOException
*/
(Stringremote,FTPClientftpClient)throwsIOException{
UploadStatusstatus=UploadStatus.Create_Directory_Success;
Stringdirectory=remote.substring(0,remote.lastIndexOf("/")+1);
if(!directory.equalsIgnoreCase("/")&&!ftpClient.changeWorkingDirectory(newString(directory.getBytes("GBK"),"iso-8859-1"))){
//如果远程目录不存在,则递归创建远程服务器目录
intstart=0;
intend=0;
if(directory.startsWith("/")){
start=1;
}else{
start=0;
}
end=directory.indexOf("/",start);
while(true){
StringsubDirectory=newString(remote.substring(start,end).getBytes("GBK"),"iso-8859-1");
if(!ftpClient.changeWorkingDirectory(subDirectory)){
if(ftpClient.makeDirectory(subDirectory)){
ftpClient.changeWorkingDirectory(subDirectory);
}else{
System.out.println("创建目录失败");
returnUploadStatus.Create_Directory_Fail;
}
}
start=end+1;
end=directory.indexOf("/",start);
//检查所有目录是否创建完毕
if(end<=start){
break;
}
}
}
returnstatus;
}
/**
*上传文件到服务器,新上传和断点续传
*@paramremoteFile远程文件名,在上传之前已经将服务器工作目录做了改变
*@paramlocalFile本地文件File句柄,绝对路径
*@paramprocessStep需要显示的处理进度步进值
*@paramftpClientFTPClient引用
*@return
*@throwsIOException
*/
publicUploadStatusuploadFile(StringremoteFile,FilelocalFile,FTPClientftpClient,longremoteSize)throwsIOException{
UploadStatusstatus;
//显示进度的上传
longstep=localFile.length()/100;
longprocess=0;
longlocalreadbytes=0L;
RandomAccessFileraf=newRandomAccessFile(localFile,"r");
OutputStreamout=ftpClient.appendFileStream(newString(remoteFile.getBytes("GBK"),"iso-8859-1"));
//断点续传
if(remoteSize>0){
ftpClient.setRestartOffset(remoteSize);
process=remoteSize/step;
raf.seek(remoteSize);
localreadbytes=remoteSize;
}
byte[]bytes=newbyte[1024];
intc;
while((c=raf.read(bytes))!=-1){
out.write(bytes,0,c);
localreadbytes+=c;
if(localreadbytes/step!=process){
process=localreadbytes/step;
System.out.println("上传进度:"+process);
//TODO汇报上传状态
}
}
out.flush();
raf.close();
out.close();
booleanresult=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;
}
returnstatus;
}
publicstaticvoidmain(String[]args){
ContinueFTPmyFtp=newContinueFTP();
try{
System.err.println(myFtp.connect("10.10.6.236",21,"5","jieyan"));
// myFtp.ftpClient.makeDirectory(newString("歌曲".getBytes("GBK"),"iso-8859-1"));
// myFtp.ftpClient.changeWorkingDirectory(newString("歌曲".getBytes("GBK"),"iso-8859-1"));
// myFtp.ftpClient.makeDirectory(newString("爱你等于爱自己".getBytes("GBK"),"iso-8859-1"));
// System.out.println(myFtp.upload("E:\yw.flv","/yw.flv",5));
// System.out.println(myFtp.upload("E:\爱你等于爱自己.mp4","/爱你等于爱自己.mp4"));
//System.out.println(myFtp.download("/爱你等于爱自己.mp4","E:\爱你等于爱自己.mp4"));
myFtp.disconnect();
}catch(IOExceptione){
System.out.println("连接FTP出错:"+e.getMessage());
}
}
}