From 718cbff14bad43985897ab7d6cd25ab1e52bd847 Mon Sep 17 00:00:00 2001
From: Matthew Kennedy <matthewkennedy@outlook.com>
Date: Tue, 22 Dec 2020 15:48:55 -0800
Subject: [PATCH] use token for sensor listener unsubscribe (#2120)

* api

* ioutil
---
 .../autotest/src/com/rusefi/IoUtil.java       | 20 +++++++++++--------
 .../java/com/rusefi/core/ISensorCentral.java  | 18 ++++++++++++++++-
 .../java/com/rusefi/core/SensorCentral.java   |  4 +++-
 3 files changed, 32 insertions(+), 10 deletions(-)

diff --git a/java_console/autotest/src/com/rusefi/IoUtil.java b/java_console/autotest/src/com/rusefi/IoUtil.java
index 6d58b2606c..410a6748eb 100644
--- a/java_console/autotest/src/com/rusefi/IoUtil.java
+++ b/java_console/autotest/src/com/rusefi/IoUtil.java
@@ -3,6 +3,7 @@ package com.rusefi;
 import com.devexperts.logging.Logging;
 import com.rusefi.config.generated.Fields;
 import com.rusefi.core.EngineState;
+import com.rusefi.core.ISensorCentral;
 import com.rusefi.core.Sensor;
 import com.rusefi.core.SensorCentral;
 import com.rusefi.io.CommandQueue;
@@ -73,18 +74,21 @@ public class IoUtil {
         long time = System.currentTimeMillis();
 
         final CountDownLatch rpmLatch = new CountDownLatch(1);
-        SensorCentral.SensorListener listener = value -> {
-            double actualRpm = SensorCentral.getInstance().getValue(Sensor.RPM);
+
+        SensorCentral.ListenerToken listenerToken = SensorCentral.getInstance().addListener(Sensor.RPM, actualRpm -> {
             if (isCloseEnough(rpm, actualRpm))
                 rpmLatch.countDown();
-        };
-        SensorCentral.getInstance().addListener(Sensor.RPM, listener);
+        });
+
+        // Wait for RPM to change
         try {
             rpmLatch.await(40, TimeUnit.SECONDS);
         } catch (InterruptedException e) {
             throw new IllegalStateException(e);
         }
-        SensorCentral.getInstance().removeListener(Sensor.RPM, listener);
+
+        // We don't need to listen to RPM any more
+        listenerToken.remove();
 
         double actualRpm = SensorCentral.getInstance().getValue(Sensor.RPM);
 
@@ -97,11 +101,11 @@ public class IoUtil {
     static void waitForFirstResponse() throws InterruptedException {
         log.info("Let's give it some time to start...");
         final CountDownLatch startup = new CountDownLatch(1);
-        SensorCentral.SensorListener listener = value -> startup.countDown();
         long waitStart = System.currentTimeMillis();
-        SensorCentral.getInstance().addListener(Sensor.RPM, listener);
+
+        ISensorCentral.ListenerToken listener = SensorCentral.getInstance().addListener(Sensor.RPM, value -> startup.countDown());
         startup.await(5, TimeUnit.SECONDS);
-        SensorCentral.getInstance().removeListener(Sensor.RPM, listener);
+        listener.remove();
         FileLog.MAIN.logLine("Got first signal in " + (System.currentTimeMillis() - waitStart));
     }
 
diff --git a/java_console/models/src/main/java/com/rusefi/core/ISensorCentral.java b/java_console/models/src/main/java/com/rusefi/core/ISensorCentral.java
index 5824a25a48..a69994c643 100644
--- a/java_console/models/src/main/java/com/rusefi/core/ISensorCentral.java
+++ b/java_console/models/src/main/java/com/rusefi/core/ISensorCentral.java
@@ -7,7 +7,23 @@ package com.rusefi.core;
 public interface ISensorCentral extends ISensorHolder {
     void setAnySensorListener(SensorCentral.SensorListener2 anySensorListener);
 
-    void addListener(Sensor sensor, SensorCentral.SensorListener listener);
+    public class ListenerToken {
+        private ISensorCentral sensorCentralInstance;
+        private Sensor sensor;
+        private SensorCentral.SensorListener listener;
+
+        public ListenerToken(ISensorCentral instance, Sensor sensor, SensorCentral.SensorListener listener) {
+            this.sensorCentralInstance = instance;
+            this.sensor = sensor;
+            this.listener = listener;
+        }
+
+        public void remove() {
+            sensorCentralInstance.removeListener(sensor, listener);
+        }
+    }
+
+    SensorCentral.ListenerToken addListener(Sensor sensor, SensorCentral.SensorListener listener);
 
     void removeListener(Sensor sensor, SensorCentral.SensorListener listener);
 
diff --git a/java_console/models/src/main/java/com/rusefi/core/SensorCentral.java b/java_console/models/src/main/java/com/rusefi/core/SensorCentral.java
index c377e42cd2..ecfe4b44e4 100644
--- a/java_console/models/src/main/java/com/rusefi/core/SensorCentral.java
+++ b/java_console/models/src/main/java/com/rusefi/core/SensorCentral.java
@@ -62,7 +62,7 @@ public class SensorCentral implements ISensorCentral {
     }
 
     @Override
-    public void addListener(Sensor sensor, SensorListener listener) {
+    public ListenerToken addListener(Sensor sensor, SensorListener listener) {
         List<SensorListener> listeners;
         synchronized (allListeners) {
             listeners = allListeners.get(sensor);
@@ -71,6 +71,8 @@ public class SensorCentral implements ISensorCentral {
             allListeners.put(sensor, listeners);
         }
         listeners.add(listener);
+
+        return new SensorCentral.ListenerToken(this, sensor, listener);
     }
 
     @Override