Java 基于 Telnet 的应用程序

Question

我想创建基于 Java 的 Telnet 应用程序，它可以将 telnet 命令发送到某个服务器并捕获它的响应，在简单的命令行 Telnet 模拟器中，请提供一些创建教程。

我看到几个教程需要 java telnet 服务器和客户端，但我的情况我只需要发送命令并将 telnet 输出捕获到变量或写入文本文件

谢谢。

Answer 1

看看 Apache Commons Net TelnetClient. It could easily provide the behaviuor you need. You just have to get the TelnetClient instance, call the connect method and work with remote server via Input- and OutputStreams. Here 你可以找到一个官方示例，它是如何使用的，但它有点多余，IMO。

这是 here 中的另一个示例：

import org.apache.commons.net.telnet.TelnetClient;

import java.io.InputStream;
import java.io.PrintStream;

public class AutomatedTelnetClient {
    private TelnetClient telnet = new TelnetClient();
    private InputStream in;
    private PrintStream out;
    private String prompt = "%";

    public AutomatedTelnetClient(String server, String user, String password) {
        try {
            // Connect to the specified server
            telnet.connect(server, 23);

            // Get input and output stream references
            in = telnet.getInputStream();
            out = new PrintStream(telnet.getOutputStream());

            // Log the user on
            readUntil("login: ");
            write(user);
            readUntil("Password: ");
            write(password);

            // Advance to a prompt
            readUntil(prompt + " ");
        } 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 {
            AutomatedTelnetClient telnet = new AutomatedTelnetClient(
                    "myserver", "userId", "Password");
            System.out.println("Got Connection...");
            telnet.sendCommand("ps -ef ");
            System.out.println("run command");
            telnet.sendCommand("ls ");
            System.out.println("run command 2");
            telnet.disconnect();
            System.out.println("DONE");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

Java 基于 Telnet 的应用程序

Java based Telnet Application

java

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