From a871e3cf2f8a5090693878f7b664ab20c4b2a2fa Mon Sep 17 00:00:00 2001
From: Ivan Olexyn <ivan@olexyn.com>
Date: Tue, 21 Apr 2020 00:34:12 +0200
Subject: [PATCH] ~ better sync.

---
 mispbridge/src/core/BridgeServlet.java |   5 +-
 mispclient/src/core/ClientServlet.java |  28 ++---
 misphelper/src/core/Ride.java          |  10 +-
 mispmock/src/core/BridgeMock.java      | 140 ++++++++++++-------------
 mispmock/src/core/ClientMock.java      |  19 ++--
 mispmock/src/core/Main.java            |   2 +-
 6 files changed, 101 insertions(+), 103 deletions(-)

diff --git a/mispbridge/src/core/BridgeServlet.java b/mispbridge/src/core/BridgeServlet.java
index dc86f99..3f31fe9 100644
--- a/mispbridge/src/core/BridgeServlet.java
+++ b/mispbridge/src/core/BridgeServlet.java
@@ -14,8 +14,9 @@ public class BridgeServlet extends HttpServlet {
 
     protected static final String MISP_CLIENT_URL = "http://localhost:9090/mispclient/core";
 
-    public final Map<Long, Ride> rideMap = new HashMap<>();
-    protected RideMapHelper mapHelper = new RideMapHelper(rideMap);
+    public final Map<Long, Ride> available = new HashMap<>();
+    public final Map<Long, Ride> booked = new HashMap<>();
+    public final Map<Long, Ride> loaded = new HashMap<>();
 
     // #######
     //
diff --git a/mispclient/src/core/ClientServlet.java b/mispclient/src/core/ClientServlet.java
index f4175ac..69d2662 100644
--- a/mispclient/src/core/ClientServlet.java
+++ b/mispclient/src/core/ClientServlet.java
@@ -9,8 +9,6 @@ import java.util.HashMap;
 import java.util.Map;
 
 
-
-
 public class ClientServlet extends HttpServlet {
 
     protected static final String MISP_BRIDGE_URL = "http://localhost:9090/mispbridge/core";
@@ -20,8 +18,10 @@ public class ClientServlet extends HttpServlet {
     public static final int AVAILABLE_RIDES_OVERHEAD = 32;
 
 
-    public final Map<Long, Ride> rideMap = new HashMap<>();
-    protected RideMapHelper mapHelper = new RideMapHelper(rideMap);
+    public final Map<Long, Ride> available = new HashMap<>();
+    public final Map<Long, Ride> booked = new HashMap<>();
+    public final Map<Long, Ride> loaded = new HashMap<>();
+
 
     public ClientServlet() {
 
@@ -41,8 +41,7 @@ public class ClientServlet extends HttpServlet {
         HttpURLConnection connection = ConnectionHelper.make("POST", MISP_BRIDGE_URL);
 
         // send POST (Ride)
-
-        rideMap.put(ride.getID(), ride.setState(State.AVAILABLE));
+        available.put(ride.getID(), ride);
         connection.setDoOutput(true);
         DataOutputStream outputStream = new DataOutputStream(connection.getOutputStream());
         outputStream.writeBytes(ride.json());
@@ -61,7 +60,6 @@ public class ClientServlet extends HttpServlet {
     }
 
 
-
     /**
      * # send GET (Request) to App
      */
@@ -100,7 +98,7 @@ public class ClientServlet extends HttpServlet {
         if (connection.getResponseCode() == 200) {
             Ride shellIdRide = ConnectionHelper.parseRide(connection);
             if (shellIdRide.getID() != null) {
-                rideMap.remove(oldRide.getID());
+                loaded.remove(oldRide.getID());
             }
         }
     }
@@ -125,18 +123,8 @@ class PostRideRunnable implements Runnable {
     @Override
     public void run() {
         while (true) {
-
-            long availableRides = 0L;
-            for (Map.Entry<Long,Ride> entry : clientServlet.rideMap.entrySet()){
-                if (entry.getValue().getState() == State.AVAILABLE){
-                    availableRides++;
-                }
-            }
-
-
-
-            if (availableRides< ClientServlet.AVAILABLE_RIDES_OVERHEAD_TRIGGER) {
-                for (int i=0; i<ClientServlet.AVAILABLE_RIDES_OVERHEAD;i++) {
+            if (clientServlet.available.size() < ClientServlet.AVAILABLE_RIDES_OVERHEAD_TRIGGER) {
+                for (int i = 0; i < ClientServlet.AVAILABLE_RIDES_OVERHEAD; i++) {
                     try {clientServlet.sendPostRide(new Ride());} catch (IOException | ServletException | InterruptedException e) { e.printStackTrace(); }
                 }
             }
diff --git a/misphelper/src/core/Ride.java b/misphelper/src/core/Ride.java
index 224ae7d..517ea7e 100644
--- a/misphelper/src/core/Ride.java
+++ b/misphelper/src/core/Ride.java
@@ -9,7 +9,7 @@ public class Ride {
 
     private static long count = 0L;
 
-    private Long id;
+    final private Long id;
     private String request;
     private String data;
     private State state;
@@ -24,6 +24,7 @@ public class Ride {
     }
 
     public Ride(String jsonString) {
+
         JSONObject obj = new JSONObject();
         try {
             obj = new JSONObject(jsonString);
@@ -32,13 +33,14 @@ public class Ride {
         }
 
 
-
+        Long _id;
 
         try {
-            id = obj.getLong("id");
+            _id = obj.getLong("id");
         }catch (JSONException e){
-            id = count++;
+            _id = count++;
         }
+        id = _id;
         try{
             request = obj.getString("request");
         } catch (JSONException e){
diff --git a/mispmock/src/core/BridgeMock.java b/mispmock/src/core/BridgeMock.java
index acef571..5207f03 100644
--- a/mispmock/src/core/BridgeMock.java
+++ b/mispmock/src/core/BridgeMock.java
@@ -28,51 +28,61 @@ public class BridgeMock extends BridgeServlet {
     @Override
     protected void handleGetRequest(HttpServletRequest request, HttpServletResponse response) throws IOException, InterruptedException {
 
-        ExchangeMock exchange;
-        Ride ride = null;
+        final ExchangeMock exchange;
+        final Ride ride;
 
         synchronized (exchange = ((RequestMock) request).exchange) {
             String parsedRequest = IOUtils.toString(request.getReader());
-            JSONObject obj = new JSONObject(parsedRequest);
+            final JSONObject obj = new JSONObject(parsedRequest);
             parsedRequest = obj.getString("request");
 
+            synchronized (available) {
 
-            synchronized (rideMap) {
-
-                // TODO make 3 maps
-                while (mapHelper.containsLess(1, State.AVAILABLE)) { Thread.sleep(Main.WAIT_SPEED); }
-                while (ride == null) {
-                    ride = mapHelper.pickAvailable();
+                while (available.size() < 1) {
+                    available.notify();
                     Thread.sleep(Main.WAIT_SPEED);
+                    available.wait();
                 }
+                // ride exists only locally, thus safe
+                ride = available.entrySet().iterator().next().getValue();
+                // ride exists only in "available", access through which is sync, thus safe
+                available.remove(ride.getID());
+                // needed because POST (Ride) wait()s
+                available.notify();
+            }
 
+            synchronized (booked) {
+                // ride exists only locally, thus safe
+                booked.put(ride.getID(), ride);
+                // ride exists only in "booked", access through which is sync, thus safe
+                ride.setRequest(parsedRequest);
+                // POST (Ride) wait()s
+                booked.notify();
+            }
 
+            synchronized (loaded) {
 
-                    
-
-                    ride.setRequest(parsedRequest);
-                    ride.setState(State.BOOKED);
-
-                    while (ride.getState() != State.LOADED) {
-                        rideMap.notify();
-                        Thread.sleep(Main.WAIT_SPEED);
-                        rideMap.wait();
-                    }
+                while (!loaded.containsKey(ride.getID())) {
+                    loaded.notify();
+                    Thread.sleep(Main.WAIT_SPEED);
+                    loaded.wait();
+                }
 
-                    rideMap.remove(ride.getID());
 
-                    exchange.response.setStatus(200);
-                    PrintWriter writer = exchange.response.getWriter();
-                    writer.write(ride.getData());
-                    writer.flush();
-                    writer.close();
-                    
+                // WIP this is tricky
+                // what if ride exists in another map, e.g. "available'
+                // in that case illegal access is possible
+                // be carefull to removing ride from all other references, when adding it to "loaded".
+                ride.setData(loaded.remove(ride.getID()).getData());
+            }
 
+            exchange.response.setStatus(200);
+            final PrintWriter writer = exchange.response.getWriter();
+            writer.write(ride.getData());
+            writer.flush();
+            writer.close();
 
-                rideMap.notify();
-            }
             exchange.notify();
-
         }
     }
 
@@ -91,34 +101,24 @@ public class BridgeMock extends BridgeServlet {
      */
     protected void handleGetRideRequestData(HttpServletRequest request, HttpServletResponse response) throws IOException, InterruptedException {
 
-        ExchangeMock exchange;
-        Ride thisRide;
+        final ExchangeMock exchange;
 
         synchronized (exchange = ((RequestMock) request).exchange) {
 
-            String jsonPayload = IOUtils.toString(request.getReader());
-            Ride parsedRide = new Ride(jsonPayload);
-
-            synchronized (rideMap) {
+            final String jsonPayload = IOUtils.toString(request.getReader());
+            final Ride ride = new Ride(jsonPayload);
 
-                synchronized (thisRide = rideMap.get(parsedRide.getID())) {
-
-                    thisRide.setData(parsedRide.getData());
-                    thisRide.setState(State.LOADED);
-
-                    exchange.response.setStatus(200);
-                    PrintWriter writer = response.getWriter();
-                    writer.write(thisRide.json());
-                    writer.flush();
-                    writer.close();
+            synchronized (booked) {
+                booked.remove(ride.getID());
+            }
 
-                    rideMap.remove(thisRide.getID());
-                    thisRide.notify();
-                }
-                rideMap.notify();
+            synchronized (loaded) {
+                loaded.put(ride.getID(), ride);
+                loaded.notify();
             }
             exchange.notify();
         }
+
     }
 
 
@@ -130,36 +130,36 @@ public class BridgeMock extends BridgeServlet {
     @Override
     protected void handlePostRide(HttpServletRequest request, HttpServletResponse response) throws IOException, InterruptedException {
 
-        ExchangeMock exchange;
-        Ride ride;
+        final ExchangeMock exchange;
+
 
         synchronized (exchange = ((RequestMock) request).exchange) {
 
             String jsonPayload = IOUtils.toString(request.getReader());
-            ride = new Ride(jsonPayload);
+            final Ride ride = new Ride(jsonPayload);
 
-            synchronized (rideMap) {
-
-                rideMap.put(ride.getID(), ride.setState(State.AVAILABLE));
+            synchronized (available) {
+                available.put(ride.getID(), ride);
+                available.notify();
+            }
 
-                synchronized (ride = rideMap.get(ride.getID())) {
+            // ID is final/threadsafe
+            while(!(booked.containsKey(ride.getID()))){
+                Thread.sleep(Main.WAIT_SPEED);
+            }
 
-                    while (ride.getState() == State.AVAILABLE) {
-                        rideMap.notify();
-                        Thread.sleep(Main.WAIT_SPEED);
-                        rideMap.wait();
-                    }
+            synchronized (booked) {
+                //booked.notify();
+                //booked.wait();
+                ride.setRequest(booked.get(ride.getID()).getRequest());
+            }
 
-                    exchange.response.setStatus(200);
-                    PrintWriter writer = response.getWriter();
-                    writer.write(ride.json());
-                    writer.flush();
-                    writer.close();
+            exchange.response.setStatus(200);
+            PrintWriter writer = response.getWriter();
+            writer.write(ride.json());
+            writer.flush();
+            writer.close();
 
-                    ride.notify();
-                }
-                rideMap.notify();
-            }
             exchange.notify();
         }
     }
diff --git a/mispmock/src/core/ClientMock.java b/mispmock/src/core/ClientMock.java
index a69fbc4..5acb9ca 100644
--- a/mispmock/src/core/ClientMock.java
+++ b/mispmock/src/core/ClientMock.java
@@ -24,11 +24,16 @@ public class ClientMock extends ClientServlet {
     @Override
     void sendPostRide(Ride ride) throws IOException, ServletException, InterruptedException {
 
-        rideMap.put(ride.getID(), ride.setState(State.AVAILABLE));
 
-        // Mock Exchange
-        ExchangeMock exchange = new ExchangeMock();
 
+
+        synchronized (available){
+            available.put(ride.getID(),ride);
+        }
+
+
+        // Mock Exchange
+        final ExchangeMock exchange = new ExchangeMock();
         exchange.request.setMethod("POST");
         exchange.request.setContentType("application/json");
         exchange.request.setContent(ride.json().getBytes());
@@ -45,7 +50,8 @@ public class ClientMock extends ClientServlet {
 
             exchange.notify();
         }
-        ride.setState(State.BOOKED);
+        available.remove(ride.getID());
+        booked.put(ride.getID(),ride);
         sendGetRequest(ride);
     }
 
@@ -74,7 +80,8 @@ public class ClientMock extends ClientServlet {
             ride.setData(parsedRide.getData());
             exchange.notify();
         }
-        ride.setState(State.LOADED);
+        booked.remove(ride.getID());
+        loaded.put(ride.getID(),ride);
         sendGetRideRequestData(ride);
     }
 
@@ -100,7 +107,7 @@ public class ClientMock extends ClientServlet {
 
             // handle OK (Ride)
             Ride parsedRide = new Ride(exchange.response.getContentAsString());
-            rideMap.remove(parsedRide.getID());
+            loaded.remove(parsedRide.getID());
             exchange.notify();
         }
     }
diff --git a/mispmock/src/core/Main.java b/mispmock/src/core/Main.java
index f09ccc7..2d5dab7 100644
--- a/mispmock/src/core/Main.java
+++ b/mispmock/src/core/Main.java
@@ -5,7 +5,7 @@ import actor.UserMock;
 
 public class Main {
 
-    final public static int WAIT_SPEED = 10;
+    final public static int WAIT_SPEED = 0;