Question

用java怎么获取ftp上的文件

Answer 1

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:/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() > 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。