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？