Decentralized Instant Messaging Protocol (Java)

Dependencies

• Latest Versions

Name	Version	Description
Cryptography		Crypto Keys
Ming Ke Ming (名可名)		Decentralized User Identity Authentication
Dao Ke Dao (道可道)		Universal Message Module

Examples

Extends Command

• Handshake Command Protocol 0. (C-S) handshake start
  1. (S-C) handshake again with new session
  2. (C-S) handshake restart with new session
  3. (S-C) handshake success

public enum HandshakeState {
    START,    // C -> S, without session key(or session expired)
    AGAIN,    // S -> C, with new session key
    RESTART,  // C -> S, with new session key
    SUCCESS;  // S -> C, handshake accepted

    public static HandshakeState checkState(String title, String session) {
        assert title != null : "handshake title should not be empty";
        if (title.equals("DIM!")/* || text.equals("OK!")*/) {
            return SUCCESS;
        } else if (title.equals("DIM?")) {
            return AGAIN;
        } else if (session == null) {
            return START;
        } else {
            return RESTART;
        }
    }

}

/**
 *  Handshake command message
 *
 *  <blockquote><pre>
 *  data format: {
 *      type : 0x88,
 *      sn   : 123,
 *
 *      command : "handshake",    // command name
 *      title   : "Hello world!", // "DIM?", "DIM!"
 *      session : "{SESSION_KEY}" // session key
 *  }
 *  </pre></blockquote>
 */
public interface HandshakeCommand extends Command {

    String HANDSHAKE = "handshake";

    String getTitle();
    String getSessionKey();

    HandshakeState getState();

    static HandshakeCommand start() {
        return new BaseHandshakeCommand("Hello world!", null);
    }

    static HandshakeCommand restart(String sessionKey) {
        return new BaseHandshakeCommand("Hello world!", sessionKey);
    }

    static HandshakeCommand again(String sessionKey) {
        return new BaseHandshakeCommand("DIM?", sessionKey);
    }

    static HandshakeCommand success(String sessionKey) {
        return new BaseHandshakeCommand("DIM!", sessionKey);
    }
}

public class BaseHandshakeCommand extends BaseCommand implements HandshakeCommand {

    public BaseHandshakeCommand(Map<String, Object> content) {
        super(content);
    }

    public BaseHandshakeCommand(String text, String session) {
        super(HANDSHAKE);
        // text message
        assert text != null : "new handshake command error";
        put("title", text);
        // session key
        if (session != null) {
            put("session", session);
        }
    }

    @Override
    public String getTitle() {
        return getString("title", null);
    }

    @Override
    public String getSessionKey() {
        return getString("session", null);
    }

    @Override
    public HandshakeState getState() {
        return HandshakeState.checkState(getTitle(), getSessionKey());
    }

}

Extends Content

/**
 *  Content for Application 0nly
 *
 *  <blockquote><pre>
 *  data format: {
 *      "type" : i2s(0xA0),
 *      "sn"   : 123,
 *
 *      "app"   : "{APP_ID}",  // application (e.g.: "chat.dim.sechat")
 *      "extra" : info         // others
 *  }
 *  </pre></blockquote>
 */
public interface AppContent extends Content {

    // get App ID
    String getApplication();

}

/**
 *  Customized Content
 *
 *  <blockquote><pre>
 *  data format: {
 *      "type" : i2s(0xCC),
 *      "sn"   : 123,
 *
 *      "app"   : "{APP_ID}",  // application (e.g.: "chat.dim.sechat")
 *      "mod"   : "{MODULE}",  // module name (e.g.: "drift_bottle")
 *      "act"   : "{ACTION}",  // action name (3.g.: "throw")
 *      "extra" : info         // action parameters
 *  }
 *  </pre></blockquote>
 */
public interface CustomizedContent extends Content {

    // get Module Name
    String getModule();

    // get Action Name
    String getAction();

    //
    //  Factory methods
    //

    static CustomizedContent create(String app, String mod, String act) {
        return new AppCustomizedContent(app, mod, act);
    }

    static CustomizedContent create(String type, String app, String mod, String act) {
        return new AppCustomizedContent(type, app, mod, act);
    }

}

public class AppCustomizedContent extends BaseContent implements AppContent, CustomizedContent {

    public AppCustomizedContent(Map<String, Object> content) {
        super(content);
    }

    public AppCustomizedContent(String type, String app, String mod, String act) {
        super(type);
        put("app", app);
        put("mod", mod);
        put("act", act);
    }

    public AppCustomizedContent(String app, String mod, String act) {
        super(ContentType.CUSTOMIZED);
        put("app", app);
        put("mod", mod);
        put("act", act);
    }

    //-------- getters --------

    @Override
    public String getApplication() {
        return getString("app", "");
    }

    @Override
    public String getModule() {
        return getString("mod", "");
    }

    @Override
    public String getAction() {
        return getString("act", "");
    }

}

Extends ID Address

• Examples in Plugins

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Copyright © 2018-2026 Albert Moky