Do not leak running pools from the internal collection (#3885)

Signed-off-by: Jörg Sautter <[email protected]>
openhab · Nov 24, 2023 · 32237a9 · 32237a9
1 parent f71ebfb
commit 32237a9
Showing 1 changed file with 23 additions and 36 deletions.
diff --git a/bundles/org.openhab.core/src/main/java/org/openhab/core/common/ThreadPoolManager.java b/bundles/org.openhab.core/src/main/java/org/openhab/core/common/ThreadPoolManager.java
@@ -18,7 +18,6 @@
 import java.util.Map;
 import java.util.Map.Entry;
 import java.util.Set;
-import java.util.WeakHashMap;
 import java.util.concurrent.Callable;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ExecutionException;
@@ -74,7 +73,7 @@ public class ThreadPoolManager {
     protected static final long THREAD_TIMEOUT = 65L;
     protected static final long THREAD_MONITOR_SLEEP = 60000;
 
-    protected static Map<String, ExecutorService> pools = new WeakHashMap<>();
+    protected static Map<String, ExecutorService> pools = new ConcurrentHashMap<>();
 
     private static Map<String, Integer> configs = new ConcurrentHashMap<>();
 
@@ -124,23 +123,17 @@ protected void modified(Map<String, Object> properties) {
      * @return an instance to use
      */
     public static ScheduledExecutorService getScheduledPool(String poolName) {
-        ExecutorService pool = pools.get(poolName);
-        if (pool == null) {
-            synchronized (pools) {
-                // do a double check if it is still null or if another thread might have created it meanwhile
-                pool = pools.get(poolName);
-                if (pool == null) {
-                    int cfg = getConfig(poolName);
-                    pool = new WrappedScheduledExecutorService(cfg,
-                            new NamedThreadFactory(poolName, true, Thread.NORM_PRIORITY));
-                    ((ThreadPoolExecutor) pool).setKeepAliveTime(THREAD_TIMEOUT, TimeUnit.SECONDS);
-                    ((ThreadPoolExecutor) pool).allowCoreThreadTimeOut(true);
-                    ((ScheduledThreadPoolExecutor) pool).setRemoveOnCancelPolicy(true);
-                    pools.put(poolName, pool);
-                    LOGGER.debug("Created scheduled thread pool '{}' of size {}", poolName, cfg);
-                }
-            }
-        }
+        ExecutorService pool = pools.computeIfAbsent(poolName, (name) -> {
+            int cfg = getConfig(name);
+            ScheduledThreadPoolExecutor executor = new WrappedScheduledExecutorService(cfg,
+                    new NamedThreadFactory(name, true, Thread.NORM_PRIORITY));
+            executor.setKeepAliveTime(THREAD_TIMEOUT, TimeUnit.SECONDS);
+            executor.allowCoreThreadTimeOut(true);
+            executor.setRemoveOnCancelPolicy(true);
+            LOGGER.debug("Created scheduled thread pool '{}' of size {}", name, cfg);
+            return executor;
+        });
+
         if (pool instanceof ScheduledExecutorService service) {
             return new UnstoppableScheduledExecutorService(poolName, service);
         } else {
@@ -156,21 +149,15 @@ public static ScheduledExecutorService getScheduledPool(String poolName) {
      * @return an instance to use
      */
     public static ExecutorService getPool(String poolName) {
-        ExecutorService pool = pools.get(poolName);
-        if (pool == null) {
-            synchronized (pools) {
-                // do a double check if it is still null or if another thread might have created it meanwhile
-                pool = pools.get(poolName);
-                if (pool == null) {
-                    int cfg = getConfig(poolName);
-                    pool = QueueingThreadPoolExecutor.createInstance(poolName, cfg);
-                    ((ThreadPoolExecutor) pool).setKeepAliveTime(THREAD_TIMEOUT, TimeUnit.SECONDS);
-                    ((ThreadPoolExecutor) pool).allowCoreThreadTimeOut(true);
-                    pools.put(poolName, pool);
-                    LOGGER.debug("Created thread pool '{}' with size {}", poolName, cfg);
-                }
-            }
-        }
+        ExecutorService pool = pools.computeIfAbsent(poolName, (name) -> {
+            int cfg = getConfig(name);
+            ThreadPoolExecutor executor = QueueingThreadPoolExecutor.createInstance(name, cfg);
+            executor.setKeepAliveTime(THREAD_TIMEOUT, TimeUnit.SECONDS);
+            executor.allowCoreThreadTimeOut(true);
+            LOGGER.debug("Created thread pool '{}' with size {}", name, cfg);
+            return executor;
+        });
+
         return new UnstoppableExecutorService<>(poolName, pool);
     }
 
@@ -179,9 +166,9 @@ static ThreadPoolExecutor getPoolUnwrapped(String poolName) {
         return (ThreadPoolExecutor) ret.getDelegate();
     }
 
-    static ThreadPoolExecutor getScheduledPoolUnwrapped(String poolName) {
+    static ScheduledThreadPoolExecutor getScheduledPoolUnwrapped(String poolName) {
         UnstoppableExecutorService<?> ret = (UnstoppableScheduledExecutorService) getScheduledPool(poolName);
-        return (ThreadPoolExecutor) ret.getDelegate();
+        return (ScheduledThreadPoolExecutor) ret.getDelegate();
     }
 
     protected static int getConfig(String poolName) {