如何使用java在没有密码的情况下ssh到主机上

KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
keyPairGenerator.initialize(2048);
KeyPair keyPair = keyPairGenerator.generateKeyPair();

Path authorizedKeysPath = Paths.get("/path/to/authorized_keys");
Files.write(authorizedKeysPath, keyPair.getPublic().getEncoded());

JSch jsch = new JSch();
jsch.addIdentity("/path/to/private/key", null, null);
Session session = jsch.getSession("username", "hostname", 22);
session.connect();

ChannelExec channel = (ChannelExec) session.openChannel("exec");
channel.setCommand("your-command-here");
channel.connect();

InputStream inputStream = channel.getInputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
String line;
while ((line = reader.readLine()) != null) {
    System.out.println(line);
}

channel.disconnect();
session.disconnect();