ganymed-ssh2使用

通过maven库获取ganymed-ssh2-262.jar，这是一个实现了ssh2协议的工具包，可以远程连接linux机器，执行命令，有些工作全靠它了

示例代码如下：

<!--首先要建立连接，传入ip（默认端口22）,登录用户名和密码-->
private static Connection getConnection(String hostname, String username, String password) throws Exception {
        Connection conn = null;
        try {
            conn = new Connection(hostname);
            conn.connect();
            boolean isAuthenticated = conn.authenticateWithPassword(username, password);
            if (isAuthenticated == false) {
                throw new IOException("Authentication failed.");
            }
        } catch (Exception e) {
            throw new IOException("username or password error.");
        }
        return conn;
}

<!--执行一条命令，传入connect相关参数，命令和超时时间-->
public static String execRemoteCommand(String hostname, String username, String password, String command, long timeout)
            throws Exception {
        Connection conn = getConnection(hostname, username, password);
        StringBuilder sb = new StringBuilder();
        Session session = null;
        try {
            session = conn.openSession();
            session.requestPTY("vt100", 80, 24, 640, 480, null);
            session.execCommand(command);
            InputStream stdout = new StreamGobbler(session.getStdout());
            BufferedReader br = new BufferedReader(new InputStreamReader(stdout));
            long start = System.currentTimeMillis();
            char[] arr = new char[512];
            int read;
            int i = 0;
            while (true) {
                read = br.read(arr, 0, arr.length);
                if (read < 0 || (System.currentTimeMillis() - start) > timeout * 1000) {
                    break;
                }
                sb.append(new String(arr, 0, read));
                i++;
            }
        } finally {
            if (session != null) {
                session.close();
            }
            if (conn != null) {
                conn.close();
            }
        }
        return sb.toString();
}

<!--执行多条命令，传入connect相关参数，命令和超时时间-->
public static String execRemoteCommand(String hostname, String username, String password, String[] command, long timeout)
            throws Exception {
        Connection conn = getConnection(hostname, username, password);
        StringBuilder sb = new StringBuilder();
        Session session = null;
        try {
            for (int t = 0; t < command.length; t++) {
                session = conn.openSession();
                session.requestPTY("vt100", 80, 24, 640, 480, null);
                session.execCommand(command[t]);
                InputStream stdout = new StreamGobbler(session.getStdout());
                BufferedReader br = new BufferedReader(new InputStreamReader(stdout));
                long start = System.currentTimeMillis();
                char[] arr = new char[512];
                int read;
                int i = 0;
                while (true) {
                    read = br.read(arr, 0, arr.length);
                    if (read < 0 || (System.currentTimeMillis() - start) > timeout * 1000) {
                        break;
                    }
                    sb.append(new String(arr, 0, read));
                    i++;
                }
                session.close();
            }
        } finally {
            if (conn != null) {
                conn.close();
            }
        }
        return sb.toString();
}

最近用这个工具包做了个远程下载的功能

OutputStream out = response.getOutputStream();
Connection conn = getConnection(sshcfg.getHost(), sshcfg.getUsername(), sshcfg.getPassword());
SCPInputStream ins=null;
try {
　　SCPClient scpClient = conn.createSCPClient();
　　ins = scpClient.get(fpath);
　　//InputStream stdout = new StreamGobbler(ins);
　　byte[] arr = new byte[512];
　　int read;
　　while (true) {
　　　　read = ins.read(arr);
　　　　if (read < 0) break;
　　　　out.write(arr);
   }
   //ins.close();
 
} finally {
　　if(ins!=null)ins.close();
　　if (conn != null) {
    　　conn.close();
　　}
}

注意：new InputStreamReader(stdout)这个的使用的是默认的字符编码，如果执行”cat **.log“而文件中有中文，应当指定编码，比如：new InputStreamReader(stdout,"GBK"),否则有可能出现乱码