javaTelnet连接的实现

import org.apache.commons.net.telnet.*;
import java.io.*;
public class TelnetSample {
private TelnetClient telnet = new TelnetClient();
private InputStream in;
private PrintStream out;
private char prompt = ';
public TelnetSample(String server, String user, String password) {
try {
telnet.connect(server, 23);
in = telnet.getInputStream();
out = new PrintStream(telnet.getOutputStream());
readUntil("ogin: ");
write(user);
readUntil("assword: ");
write(password);
} catch (Exception e) {
e.printStackTrace();
}
}
public void su(String password) {
try {
write("su");
readUntil("Password: ");
write(password);
prompt = '#';
readUntil(prompt + " ");
} catch (Exception e) {
e.printStackTrace();
}
}
public String readUntil(String pattern) {
try {
char lastChar = pattern.charAt(pattern.length() - 1);
StringBuffer sb = new StringBuffer();
boolean found = false;
char ch = (char) in.read();
while (true) {
System.out.print(ch);
sb.append(ch);
if (ch == lastChar) {
if (sb.toString().endsWith(pattern)) {
return sb.toString();
}
}
ch = (char) in.read();
}
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
public void write(String value) {
try {
out.println(value);
out.flush();
System.out.println(value);
} catch (Exception e) {
e.printStackTrace();
}
}
public String sendCommand(String command) {
try {
write(command);
return readUntil(prompt + " ");
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
public void disconnect() {
try {
telnet.disconnect();
} catch (Exception e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
try {
TelnetSample telnet = new TelnetSample("192.1***.0.***", "username","password");
telnet.sendCommand("dir ");
} catch (Exception e) {
e.printStackTrace();
}
}
}

以上为转载csdn张春雨的专栏