Implemented HAM (this is conflict resolution system)

build.gradle

@@ -14,6 +14,7 @@ repositories {
 dependencies {
     implementation 'org.java-websocket:Java-WebSocket:1.4.0'
     implementation group: 'org.json', name: 'json', version: '20180813'
+    implementation 'com.google.code.gson:gson:2.8.5'
 
     testCompile group: 'junit', name: 'junit', version: '4.12'
 }

src/main/java/io/github/chronosx88/GunJava/Client.java

@@ -0,0 +1,61 @@
+package io.github.chronosx88.GunJava;
+
+import org.java_websocket.client.WebSocketClient;
+import org.java_websocket.handshake.ServerHandshake;
+import org.json.JSONObject;
+
+import java.net.InetAddress;
+import java.net.URI;
+import java.net.URISyntaxException;
+
+public class Client extends WebSocketClient {
+    private Dup dup = new Dup();
+
+    public Client(InetAddress address, int port) throws URISyntaxException {
+        super(new URI("ws://" + address.getHostAddress() + ":" + port));
+    }
+
+    @Override
+    public void onOpen(ServerHandshake handshakeData) {
+        System.out.println("Connection open. Status: " + handshakeData.getHttpStatus());
+        Utils.setTimeout(() -> {
+            JSONObject msg = new JSONObject();
+            msg.put("#", dup.track(Dup.random(3)));
+            msg.put("put", new JSONObject()
+                    .put("ASDF", Utils.newNode("ASDF", new JSONObject()
+                            .put("name", "Mark Nadal")
+                            .put("boss", new JSONObject().put("#", "FDSA"))).toJSONObject())
+                    .put("FDSA", Utils.newNode("FDSA", new JSONObject().put("name", "Fluffy").put("species", "a kitty").put("slave", new JSONObject().put("#", "ASDF"))).toJSONObject()));
+            this.send(msg.toString());
+        }, 1000);
+        Utils.setTimeout(() -> {
+            JSONObject msg = new JSONObject();
+            msg.put("#", dup.track(Dup.random(3)));
+            msg.put("put", new JSONObject()
+                    .put("ASDF", Utils.newNode("ASDF", new JSONObject()
+                            .put("name", "Mark")).toJSONObject())
+                    .put("FDSA", Utils.newNode("FDSA", new JSONObject().put("species", "felis silvestris").put("color", "ginger")).toJSONObject()));
+            this.send(msg.toString());
+        }, 2000);
+    }
+
+    @Override
+    public void onMessage(String message) {
+        JSONObject msg = new JSONObject(message);
+        if(dup.check(msg.getString("#"))) { return; }
+        dup.track(msg.getString("#"));
+        System.out.println(msg.toString());
+        this.send(message);
+    }
+
+    @Override
+    public void onClose(int code, String reason, boolean remote) {
+        System.out.println("Connection closed. Code/reason/remote: " + code + "/" + reason + "/" + remote);
+    }
+
+    @Override
+    public void onError(Exception ex) {
+        System.out.println("Terrible fail: ");
+        ex.printStackTrace();
+    }
+}

src/main/java/io/github/chronosx88/GunJava/Dup.java

@@ -40,9 +40,9 @@ public class Dup {
         }
     }
 
-    public String random() {
+    public static String random(int len) {
         StringBuilder sb = new StringBuilder();
-        for (int i = 0; i < randomPack.length; i++) {
+        for (int i = 0; i < len; i++) {
             sb.append(randomPack[random.nextInt(randomPack.length)]);
         }
         return sb.toString();

src/main/java/io/github/chronosx88/GunJava/Graph.java

@@ -0,0 +1,62 @@
+package io.github.chronosx88.GunJava;
+
+import org.json.JSONObject;
+
+import java.util.*;
+
+public class Graph {
+
+    private final HashMap<String, Node> nodes;
+
+    public Graph(JSONObject source) {
+        nodes = new LinkedHashMap<>();
+
+        for (String soul : source.keySet())
+            nodes.put(soul, new Node(source.getJSONObject(soul)));
+    }
+
+    public Graph() {
+        nodes = new LinkedHashMap<>();
+    }
+
+    public Node getNode(String soul) {
+        return nodes.getOrDefault(soul, null);
+    }
+
+    public void addNode(String soul, Node incomingNode) {
+        nodes.put(soul, incomingNode);
+    }
+
+    public boolean hasNode(String soul) {
+        return nodes.containsKey(soul);
+    }
+
+    public Set<Map.Entry<String, Node>> entries() {
+        return nodes.entrySet();
+    }
+
+    @Override
+    public String toString() {
+        JSONObject jsonObject = new JSONObject();
+        for(Map.Entry<String, Node> entry : nodes.entrySet()) {
+            jsonObject.put(entry.getKey(), entry.getValue().toJSONObject());
+        }
+        return jsonObject.toString();
+    }
+
+    public String toPrettyString() {
+        JSONObject jsonObject = new JSONObject();
+        for(Map.Entry<String, Node> entry : nodes.entrySet()) {
+            jsonObject.put(entry.getKey(), entry.getValue().toJSONObject());
+        }
+        return jsonObject.toString(2);
+    }
+
+    public JSONObject toJSONObject() {
+        JSONObject jsonObject = new JSONObject();
+        for(Map.Entry<String, Node> entry : nodes.entrySet()) {
+            jsonObject.put(entry.getKey(), entry.getValue().toJSONObject());
+        }
+        return jsonObject;
+    }
+}

src/main/java/io/github/chronosx88/GunJava/HAM.java

@@ -0,0 +1,107 @@
+package io.github.chronosx88.GunJava;
+
+import org.json.JSONObject;
+
+import java.util.Iterator;
+import java.util.Map;
+
+public class HAM {
+    static class HAMResult {
+        public boolean defer = false;
+        public boolean historical = false;
+        public boolean converge = false;
+        public boolean incoming = false;
+        public boolean current = false;
+        public boolean state = false;
+        public String err = null;
+    }
+
+    public static HAMResult ham(long machineState, long incomingState, long currentState, Object incomingValue, Object currentValue) {
+        HAMResult result = new HAMResult();
+
+        if(machineState < incomingState) {
+            result.defer = true;
+            return result;
+        }
+        if(incomingState < currentState){
+            result.historical = true;
+            return result;
+        }
+        if(currentState < incomingState) {
+            result.converge = true;
+            result.incoming = true;
+            return result;
+        }
+        if(incomingState == currentState) {
+            if(incomingValue.equals(currentValue)) {
+                result.state = true;
+                return result;
+            }
+            if((incomingValue.toString().compareTo(currentValue.toString())) < 0) {
+                result.converge = true;
+                result.current = true;
+                return result;
+            }
+            if((currentValue.toString().compareTo(incomingValue.toString())) < 0) {
+                result.converge = true;
+                result.incoming = true;
+                return result;
+            }
+        }
+        result.err = "Invalid CRDT Data: "+ incomingValue +" to "+ currentValue +" at "+ incomingState +" to "+ currentState +"!";
+        return result;
+    }
+
+    public static Graph mix(Graph change, Graph graph) {
+        long machine = System.currentTimeMillis();
+        Graph diff = null;
+        for(Map.Entry<String, Node> entry : change.entries()) {
+            Node node = entry.getValue();
+            for(String key : node.values.keySet()) {
+                Object value = node.values.get(key);
+                if ("_".equals(key)) { continue; }
+                long state = node.states.getLong(key);
+                long was = -1;
+                Object known = null;
+                if(graph == null) {
+                    graph = new Graph();
+                }
+                if(graph.hasNode(node.soul)) {
+                    if(graph.getNode(node.soul).states.opt(key) != null) {
+                        was = graph.getNode(node.soul).states.getLong(key);
+                    }
+                    known = graph.getNode(node.soul).values.opt(key) == null ? 0 : graph.getNode(node.soul).values.opt(key);
+                }
+
+                HAMResult ham = ham(machine, state, was, value, known);
+                if(!ham.incoming) {
+                    if(ham.defer) {
+                        System.out.println("DEFER: " + key + " " + value);
+                        // FIXME
+                    }
+                    continue;
+                }
+
+                if(diff == null) {
+                    diff = new Graph();
+                }
+
+                if(!diff.hasNode(node.soul)) {
+                    diff.addNode(node.soul, Utils.newNode(node.soul, new JSONObject()));
+                }
+
+                if(!graph.hasNode(node.soul)) {
+                    graph.addNode(node.soul, Utils.newNode(node.soul, new JSONObject()));
+                }
+
+                graph.getNode(node.soul).values.put(key, value);
+                diff.getNode(node.soul).values.put(key, value);
+
+                diff.getNode(node.soul).states.put(key, state);
+                graph.getNode(node.soul).states.put(key, state);
+            }
+        }
+
+        return diff;
+    }
+}

src/main/java/io/github/chronosx88/GunJava/Main.java

@@ -1,40 +0,0 @@
-package io.github.chronosx88.GunJava;
-
-import org.java_websocket.client.WebSocketClient;
-import org.java_websocket.handshake.ServerHandshake;
-import org.json.JSONObject;
-
-import java.net.URI;
-import java.net.URISyntaxException;
-
-public class Main {
-    public static void main(String[] args) throws URISyntaxException {
-        Server server = new Server(5054);
-        server.start();
-        WebSocketClient client = new WebSocketClient(new URI("ws://127.0.0.1:5054")) {
-            @Override
-            public void onOpen(ServerHandshake handshakeData) {
-                System.out.println("open " + handshakeData.getHttpStatusMessage());
-            }
-
-            @Override
-            public void onMessage(String message) {
-                JSONObject msg = new JSONObject(message);
-                System.out.println(msg);
-                this.send(message);
-            }
-
-            @Override
-            public void onClose(int code, String reason, boolean remote) {
-                System.out.println("close " + code + " " + reason + " " + remote);
-            }
-
-            @Override
-            public void onError(Exception ex) {
-                System.out.println("error");
-                ex.printStackTrace();
-            }
-        };
-        client.connect();
-    }
-}

src/main/java/io/github/chronosx88/GunJava/MainClient.java

@@ -0,0 +1,12 @@
+package io.github.chronosx88.GunJava;
+
+import java.net.Inet4Address;
+import java.net.URISyntaxException;
+import java.net.UnknownHostException;
+
+public class MainClient {
+    public static void main(String[] args) throws URISyntaxException, UnknownHostException {
+        Client client = new Client(Inet4Address.getByAddress(new byte[]{127, 0, 0, 1}), 5054);
+        client.connect();
+    }
+}

src/main/java/io/github/chronosx88/GunJava/MainServer.java

@@ -0,0 +1,8 @@
+package io.github.chronosx88.GunJava;
+
+public class MainServer {
+    public static void main(String[] args) {
+        Server server = new Server(5054);
+        server.start();
+    }
+}

src/main/java/io/github/chronosx88/GunJava/Node.java

@@ -0,0 +1,64 @@
+package io.github.chronosx88.GunJava;
+
+import org.json.JSONObject;
+
+public class Node implements Comparable<Node> {
+    public JSONObject values; // Data
+    public final JSONObject states; // Metadata for diff
+    public final String soul; // i.e. ID of node
+
+    /**
+     * Create a Node from a JSON object.
+     *
+     * @param rawData JSON object, which contains the data
+     */
+    public Node(JSONObject rawData) {
+        this.values = rawData;
+        this.states = values.getJSONObject("_").getJSONObject(">");
+        this.soul = values.getJSONObject("_").getString("#");
+        values.remove("_");
+    }
+
+    @Override
+    public int compareTo(Node other) {
+        return soul.compareTo(other.soul);
+    }
+
+    @Override
+    public boolean equals(Object other) {
+        if (other == null)
+            return false;
+        if (other instanceof String)
+            return soul.equals(other);
+        if (other instanceof Node)
+            return compareTo((Node) other) == 0;
+        return false;
+    }
+
+    @Override
+    public int hashCode() {
+        return soul.hashCode();
+    }
+
+    public boolean isNode(String key) {
+        return values.optJSONObject(key) != null;
+    }
+
+    public Node getNode(String key, Graph g) {
+        String soulRef = values.getJSONObject(key).getString("#");
+        return g.getNode(soulRef);
+    }
+
+    @Override
+    public String toString() {
+        JSONObject jsonObject = new JSONObject(values.toString());
+        jsonObject.put("_", new JSONObject().put("#", soul).put(">", states));
+        return jsonObject.toString();
+    }
+
+    public JSONObject toJSONObject() {
+        JSONObject jsonObject = new JSONObject(values.toString());
+        jsonObject.put("_", new JSONObject().put("#", soul).put(">", states));
+        return jsonObject;
+    }
+}

src/main/java/io/github/chronosx88/GunJava/Server.java

@@ -6,12 +6,14 @@ import org.java_websocket.server.WebSocketServer;
 import org.json.JSONObject;
 
 import java.net.InetSocketAddress;
+import java.util.ArrayList;
 import java.util.Timer;
-import java.util.TimerTask;
 
 public class Server extends WebSocketServer {
     private Timer timer = new Timer(true);
     private Dup dup = new Dup();
+    private ArrayList<WebSocket> peers = new ArrayList<>();
+    private Graph graph = new Graph();
 
     public Server(int port) {
         super(new InetSocketAddress(port));
@@ -19,16 +21,7 @@ public class Server extends WebSocketServer {
 
     @Override
     public void onOpen(WebSocket conn, ClientHandshake handshake) {
-        final int[] count = {0};
+        peers.add(conn);
-        timer.schedule(new TimerTask() {
-            @Override
-            public void run() {
-                count[0] += 1;
-                JSONObject msg = new JSONObject();
-                msg.put("#", dup.track(String.valueOf(count[0])));
-                conn.send(msg.toString());
-            }
-        }, 0, 1000);
     }
 
     @Override
@@ -39,9 +32,16 @@ public class Server extends WebSocketServer {
     @Override
     public void onMessage(WebSocket conn, String message) {
         JSONObject msg = new JSONObject(message);
-        //if(dup.check(msg.getString("#"))) { return; }
+        if(dup.check(msg.getString("#"))) { return; }
         dup.track(msg.getString("#"));
-        System.out.println("received: " + msg.toString());
+        if(msg.opt("put") != null) {
+            HAM.mix(new Graph(msg.getJSONObject("put")), graph);
+            System.out.println("----------------");
+            System.out.println(graph.toPrettyString());
+        }
+        for (WebSocket peer : peers) {
+            peer.send(message);
+        }
     }
 
     @Override

src/main/java/io/github/chronosx88/GunJava/Utils.java

@@ -1,5 +1,7 @@
 package io.github.chronosx88.GunJava;
 
+import org.json.JSONObject;
+
 public class Utils {
     public static Thread setTimeout(Runnable runnable, int delay){
         Thread thread = new Thread(() -> {
@@ -14,4 +16,13 @@ public class Utils {
         thread.start();
         return thread;
     }
+
+    public static Node newNode(String soul, JSONObject data) {
+        JSONObject states = new JSONObject();
+        for (String key : data.keySet()) {
+            states.put(key, System.currentTimeMillis());
+        }
+        data.put("_", new JSONObject().put("#", soul).put(">", states));
+        return new Node(data);
+    }
 }