看着：
我想发送一个 CHAR LF，十进制值 10，还有一个 Chr 1，十进制字节值 49。然后再发送一个 LF。（我认为这是 rainmaker.wunderground.com 3000 上的 telnet 服务器所期望的序列。）这是从标准输入中捕获的键盘输入。我明确没有使用 ApacheIOUtil 示例。
有必要TelnetClient基于一个示例 WeatherTelnet 程序对 Apache 进行线程读/写。TelnetClient.sendCommand() API 指定它需要一个字节参数，我想我正在发送。但它是正确的字节吗？并正确发送？
telnet 天气服务器（见下文）预期的第一个命令是按 Enter，我认为它是一个 LF，我认为它是Byte by = 10.
似乎其他命令，如整数，是作为命令发送的，至少据我所知。任何解释此输出和调试的帮助将不胜感激：
执行 JAR：
thufir@dur:~$
thufir@dur:~$ java -jar NetBeansProjects/SSCCE/dist/SSCCE.jar
print..
------------------------------------------------------------------------------
* Welcome to THE WEATHER UNDERGROUND telnet service! *
------------------------------------------------------------------------------
* *
* National Weather Service information provided by Alden Electronics, Inc. *
* and updated each minute as reports come in over our data feed. *
* *
* **Note: If you cannot get past this opening screen, you must use a *
* different version of the "telnet" program--some of the ones for IBM *
* compatible PC's have a bug that prevents proper connection. *
* *
* comments: jmasters@wunderground.com *
------------------------------------------------------------------------------
Press Return to continue:
Press Return for menu
or enter 3 letter forecast city code--
WEATHER UNDERGROUND MAIN MENU
******************************
1) U.S. forecasts and climate data
2) Canadian forecasts
3) Current weather observations
4) Ski conditions
5) Long-range forecasts
6) Latest earthquake reports
7) Severe weather
8) Hurricane advisories
9) Weather summary for the past month
10) International data
11) Marine forecasts and observations
12) Ultraviolet light forecast
X) Exit program
C) Change scrolling to screen
H) Help and information for new users
?) Answers to all your questions
Selection:1
sent 49 cmd 1
Not a valid option. Type a number 1 to 12.
WEATHER UNDERGROUND MAIN MENU
******************************
1) U.S. forecasts and climate data
2) Canadian forecasts
3) Current weather observations
4) Ski conditions
5) Long-range forecasts
6) Latest earthquake reports
7) Severe weather
8) Hurricane advisories
9) Weather summary for the past month
10) International data
11) Marine forecasts and observations
12) Ultraviolet light forecast
X) Exit program
C) Change scrolling to screen
H) Help and information for new users
?) Answers to all your questions
Selection:1
sent 49 cmd 1
Not a valid option. Type a number 1 to 12.
WEATHER UNDERGROUND MAIN MENU
******************************
1) U.S. forecasts and climate data
2) Canadian forecasts
3) Current weather observations
4) Ski conditions
5) Long-range forecasts
6) Latest earthquake reports
7) Severe weather
8) Hurricane advisories
9) Weather summary for the past month
10) International data
11) Marine forecasts and observations
12) Ultraviolet light forecast
X) Exit program
C) Change scrolling to screen
H) Help and information for new users
?) Answers to all your questions
Selection:^Cthufir@dur:~$
thufir@dur:~$
thufir@dur:~$
thufir@dur:~$
代码：
package weathertelnet;
import java.io.BufferedReader;
import static java.lang.System.out;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.InetAddress;
import java.net.SocketException;
import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.logging.Logger;
import org.apache.commons.net.telnet.TelnetClient;
public final class Telnet {
private final static Logger LOG = Logger.getLogger(Telnet.class.getName());
private TelnetClient telnetClient = new TelnetClient();
public Telnet() throws SocketException, IOException {
InetAddress host = InetAddress.getByName("rainmaker.wunderground.com");
int port = 3000;
telnetClient.connect(host, port);
final InputStream inputStream = telnetClient.getInputStream();
final ConcurrentLinkedQueue<Character> clq = new ConcurrentLinkedQueue();
final StringBuilder sb = new StringBuilder();
Thread print = new Thread() {
@Override
public void run() {
out.println("print..");
try {
char ch = (char) inputStream.read();
while (255 > ch && ch >= 0) {
clq.add(ch);
out.print(ch);
ch = (char) inputStream.read();
}
} catch (IOException ex) {
out.println("cannot read inputStream:\t" + ex);
}
}
};
Thread read = new Thread() {
@Override
public void run() {
BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
try {
do {
String command = in.readLine();
byte[] bytes = command.getBytes();
byte b = 0;
for (int i = 0; i < bytes.length; i++) {
b = bytes[i];
String cmd = new String(bytes);
telnetClient.sendCommand(b);
out.println("sent\t" + b + "\tcmd\t" + cmd);
}
b=10;
telnetClient.sendCommand(b);
} while (true);
} catch (IOException ex) {
}
}
};
print.start();
read.start();
}
public static void main(String[] args) throws SocketException, IOException {
new Telnet();
}
}
普通电话
net:
thufir@dur:~$
thufir@dur:~$
thufir@dur:~$ telnet rainmaker.wunderground.com 3000
Trying 38.102.137.140...
Connected to rainmaker.wunderground.com.
Escape character is '^]'.
------------------------------------------------------------------------------
* Welcome to THE WEATHER UNDERGROUND telnet service! *
------------------------------------------------------------------------------
* *
* National Weather Service information provided by Alden Electronics, Inc. *
* and updated each minute as reports come in over our data feed. *
* *
* **Note: If you cannot get past this opening screen, you must use a *
* different version of the "telnet" program--some of the ones for IBM *
* compatible PC's have a bug that prevents proper connection. *
* *
* comments: jmasters@wunderground.com *
------------------------------------------------------------------------------
Press Return to continue:
Press Return for menu
or enter 3 letter forecast city code--
WEATHER UNDERGROUND MAIN MENU
******************************
1) U.S. forecasts and climate data
2) Canadian forecasts
3) Current weather observations
4) Ski conditions
5) Long-range forecasts
6) Latest earthquake reports
7) Severe weather
8) Hurricane advisories
9) Weather summary for the past month
10) International data
11) Marine forecasts and observations
12) Ultraviolet light forecast
X) Exit program
C) Change scrolling to screen
H) Help and information for new users
?) Answers to all your questions
Selection:1
CITY FORECAST MENU
---------------------------------------------------
1) Print forecast for selected city
2) Print climatic data for selected city
3) Display 3-letter city codes for a selected state
4) Display all 2-letter state codes
M) Return to main menu
X) Exit program
?) Help
Selection:x
Connection closed by foreign host.
thufir@dur:~$
thufir@dur:~$