Package org.apache.commons.net.bsd

Class RLoginClient

java.lang.Object

org.apache.commons.net.SocketClient

org.apache.commons.net.bsd.RExecClient

org.apache.commons.net.bsd.RCommandClient

org.apache.commons.net.bsd.RLoginClient

public class RLoginClient
extends RCommandClient

RLoginClient is very similar to RCommandClient, from which it is derived, and uses the rcmd() facility implemented in RCommandClient to implement the functionality of the rlogin command that first appeared in 4.2BSD Unix. rlogin is a command used to log in to a remote machine from a trusted host, sometimes without issuing a password. The trust relationship is the same as described in the documentation for RCommandClient.

As with virtually all the client classes in org.apache.commons.net, this class derives from SocketClient. But it relies on the connection methods defined in RcommandClient which ensure that the local Socket will originate from an acceptable rshell port. The way to use RLoginClient is to first connect to the server, call the rlogin() method, and then fetch the connection's input and output streams. Interaction with the remote command is controlled entirely through the I/O streams. Once you have finished processing the streams, you should invoke disconnect() to clean up properly.

The standard output and standard error streams of the remote process are transmitted over the same connection, readable from the input stream returned by getInputStream()

Unlike RExecClient and RCommandClient, it is not possible to tell the rlogind daemon to return the standard error stream over a separate connection. getErrorStream() will always return null. The standard input of the remote process can be written to through the output stream returned by getOutputSream()

See Also:

• SocketClient
• RExecClient
• RCommandClient

Field Summary

Fields

Modifier and Type	Field	Description
static final int	DEFAULT_PORT	The default rlogin port.

Fields inherited from class org.apache.commons.net.bsd.RCommandClient

MAX_CLIENT_PORT, MIN_CLIENT_PORT

Fields inherited from class org.apache.commons.net.bsd.RExecClient

_errorStream_, NULL_CHAR

Fields inherited from class org.apache.commons.net.SocketClient

_defaultPort_, _hostname_, _input_, _output_, _serverSocketFactory_, _socket_, _socketFactory_, _timeout_, connectTimeout, NETASCII_EOL, remoteInetSocketAddress

Constructor Summary

Constructors

Constructor	Description
RLoginClient()	The default RLoginClient constructor.

Method Summary

Modifier and Type	Method	Description
void	rlogin(String localUsername, String remoteUsername, String terminalType)	Same as the other rlogin method, but no terminal speed is defined.
void	rlogin(String localUsername, String remoteUsername, String terminalType, int terminalSpeed)	Logins into a remote machine through the rlogind daemon on the server to which the RLoginClient is connected.

Methods inherited from class org.apache.commons.net.bsd.RCommandClient

connect, connect, connect, connect, connect, connect, rcommand, rcommand

Methods inherited from class org.apache.commons.net.bsd.RExecClient

disconnect, getErrorStream, getInputStream, getOutputStream, isRemoteVerificationEnabled, rexec, rexec, setRemoteVerificationEnabled

Methods inherited from class org.apache.commons.net.SocketClient

_connectAction_, addProtocolCommandListener, applySocketAttributes, connect, connect, createCommandSupport, fireCommandSent, fireReplyReceived, getCharset, getCharsetName, getCommandSupport, getConnectTimeout, getDefaultPort, getDefaultTimeout, getKeepAlive, getLocalAddress, getLocalPort, getProxy, getReceiveBufferSize, getRemoteAddress, getRemoteInetSocketAddress, getRemotePort, getSendBufferSize, getServerSocketFactory, getSoLinger, getSoTimeout, getTcpNoDelay, isAvailable, isConnected, removeProtocolCommandListener, setCharset, setConnectTimeout, setDefaultPort, setDefaultTimeout, setKeepAlive, setProxy, setReceiveBufferSize, setSendBufferSize, setServerSocketFactory, setSocketFactory, setSoLinger, setSoTimeout, setTcpNoDelay, verifyRemote

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

DEFAULT_PORT

public static final int DEFAULT_PORT

The default rlogin port. Set to 513 in BSD Unix and according to RFC 1282.

See Also:

• Constant Field Values

Constructor Details

RLoginClient

public RLoginClient()

The default RLoginClient constructor. Initializes the default port to DEFAULT_PORT .

Method Details

rlogin

public void rlogin(String localUsername,
 String remoteUsername,
 String terminalType)
            throws IOException

Same as the other rlogin method, but no terminal speed is defined.

Parameters:

localUsername - the local user

remoteUsername - the remote user

terminalType - the terminal type

Throws:

IOException - on error

rlogin

public void rlogin(String localUsername,
 String remoteUsername,
 String terminalType,
 int terminalSpeed)
            throws IOException

Logins into a remote machine through the rlogind daemon on the server to which the RLoginClient is connected. After calling this method, you may interact with the remote login shell through its standard input and output streams. Standard error is sent over the same stream as standard output. You will typically be able to detect the termination of the remote login shell after reaching end of file on its standard output (accessible through getInputStream()). Disconnecting from the server or closing the process streams before reaching end of file will terminate the remote login shell in most cases.

If user authentication fails, the rlogind daemon will request that a password be entered interactively. You will be able to read the prompt from the output stream of the RLoginClient and write the password to the input stream of the RLoginClient.

Parameters:

localUsername - The user account on the local machine that is trying to log in to the remote host.

remoteUsername - The account name on the server that is being logged in to.

terminalType - The name of the user's terminal (e.g., "vt100", "network", etc.)

terminalSpeed - The speed of the user's terminal, expressed as a baud rate or bps (e.g., 9600 or 38400)

Throws:

IOException - If the rlogin() attempt fails. The exception will contain a message indicating the nature of the failure.