我使用 JSch 库开发 SFTP 客户端。
问题是两者get
,put
方法的状态是-1。
这是我的代码:
class SftpClient {
private static final Logger LOG = Logger.getLogger(SftpClient.class);
/** Connection port number */
public static final int PORT = 22;
/** SECURED protocol name */
private static final String PROTOCOL = "sftp";
/** Connection time out in milliseconds */
public static final int TIME_OUT = 5000;
/** This class serves as a central configuration point, and as a factory for Session objects configured with these settings */
private JSch _client;
/** A session represents a connection to a SSH server */
private Session _session;
/** Channel connected to a SECURED server (as a subsystem of the SSH server) */
private ChannelSftp _channelSftp;
/**
* Value returned by the last executed command.
*/
private int _exitValue;
/**
* Computer contains the url, the login and the password to connect.
*/
private Computer _computer;
/**
* Initialize a SECURED client
* @param target - Machine we want to connect to
*/
public SftpClient(Computer target) {
_client = new JSch();
_computer = target;
}
protected void connect() throws Exception {
try {
if (_client == null) {
_client = new JSch();
}
if (_session == null) {
_session = _client.getSession(_computer.getLogin(), _computer.getUrl(), PORT);
Properties props = new Properties();
props.put("StrictHostKeyChecking", "no");
props.put("compression.s2c", "zlib,none");
props.put("compression.c2s", "zlib,none");
_session.setConfig(props);
_session.setPassword(_computer.getPassword());
if (LOG.isDebugEnabled()) {
LOG.debug("Connecting to "+_computer.getUrl()+" with login "+_computer.getLogin()+"...");
}
}
if (!_session.isConnected()) {
_session.connect(TIME_OUT);
}
// disconnect previous channel if it has not been killed properly
if (_channelSftp != null && _channelSftp.isConnected()) {
_channelSftp.disconnect();
}
_channelSftp = (ChannelSftp) _session.openChannel(PROTOCOL);
_channelSftp.connect();
if (LOG.isInfoEnabled()) {
LOG.info("Connected to "+_computer.getUrl()+" with login "+_computer.getLogin());
}
} catch(JSchException e) {
LOG.error("Auth failed", e);
throw e;
}
}
protected void connect(String path) throws Exception {
connect();
if (_channelSftp != null && _channelSftp.isConnected()) {
_channelSftp.cd(path);
}
}
public boolean get(final String remoteDirectory, final String remoteFile, final String localDirectory) throws Exception {
boolean res = false;
if (LOG.isInfoEnabled()) {
LOG.info("Download file "+remoteDirectory+"/"+remoteFile+" from "+_computer+" in "+localDirectory);
}
if (remoteDirectory != null && remoteFile != null && !remoteFile.isEmpty() && localDirectory != null) {
try {
// connect to the server and change directory
connect(remoteDirectory);
// change local directory
_channelSftp.lcd(localDirectory);
// download the file, keeping the same name
_channelSftp.get(remoteFile, remoteFile);
// update exit value
_exitValue = _channelSftp.getExitStatus();
if (_exitValue == 0) {
res = true;
}
if (LOG.isDebugEnabled()) {
LOG.debug("Exit status is: "+_exitValue);
}
} catch(SftpException e){
LOG.error("Auth failed", e);
throw e;
} finally {
if (_channelSftp != null && _channelSftp.isConnected()) {
_channelSftp.disconnect();
_channelSftp.exit();
}
}
} else {
LOG.warn("Check remoteDirectory ('"+remoteDirectory+"') or remoteFile ('"+remoteFile+"') or localDirectory ('"+localDirectory+"').");
}
return res;
}
public void put(final File localFile, final String destPath) throws Exception {
if (LOG.isInfoEnabled()) {
LOG.info("Send file "+localFile+" to "+_computer+" in "+destPath);
}
if (localFile == null) {
_exitValue = -1;
LOG.error("The given local file is null. Aborting tranfer.");
return;
}
if (!localFile.exists()) {
_exitValue = -1;
LOG.error("The given local file '"+localFile+"' does not exist. Aborting tranfer.");
return;
}
final InputStream input = new FileInputStream(localFile);
if (input == null || input.available() <= 0) {
_exitValue = -1;
LOG.error("Cannot read file "+localFile);
return;
}
try {
connect(destPath);
_channelSftp.put(input, localFile.getName());
_exitValue = _channelSftp.getExitStatus();
if (LOG.isDebugEnabled()) {
LOG.debug("Exit status is: "+_exitValue);
}
} catch(SftpException e){
LOG.error("Auth failed", e);
throw e;
} finally {
if (_channelSftp != null && _channelSftp.isConnected()) {
_channelSftp.disconnect();
_channelSftp.exit();
}
IOUtils.closeQuietly(input);
}
}
public void disconnect() {
if (_channelSftp != null && _channelSftp.isConnected()) {
_channelSftp.disconnect();
_channelSftp.exit();
}
if (_session != null && _session.isConnected()) {
_session.disconnect();
if (LOG.isInfoEnabled()) {
LOG.info("SECURED FTP disconnected");
}
}
}
}
不会抛出异常。
顺便说一句,我要上传和下载的文件是tar文件。Jsch 有 FTP 二进制模式吗?
文件传输良好。我可以正确使用它们,但我担心退出状态。
我查看了Jsch API,它说:
The exit status is only available for certain types of channels, and only after the channel was closed (more exactly, just before the channel is closed).
我如何知道退出状态是否可用ChannelSftp
?