CAMEL-20613: set AbstractCamelContext#endpointStrategies to Concurren…

…tHashSet to prevent ConcurrentModificationException (#13821)

If a thread iterates over the list of strategies while another thread adds a new strategy, ConcurrentModificationException is thrown. To fix this issue, AbstractCamelContext#endpointStrategies can be set to a thread-safe collection.

core/camel-base-engine/src/main/java/org/apache/camel/impl/engine/AbstractCamelContext.java

@@ -206,7 +206,7 @@ public abstract class AbstractCamelContext extends BaseService
 
     private final DefaultCamelContextExtension camelContextExtension = new DefaultCamelContextExtension(this);
     private final AtomicInteger endpointKeyCounter = new AtomicInteger();
-    private final List<EndpointStrategy> endpointStrategies = new ArrayList<>();
+    private final Set<EndpointStrategy> endpointStrategies = ConcurrentHashMap.newKeySet();
     private final GlobalEndpointConfiguration globalEndpointConfiguration = new DefaultGlobalEndpointConfiguration();
     private final Map<String, Component> components = new ConcurrentHashMap<>();
     private final Set<Route> routes = new LinkedHashSet<>();
@@ -4203,7 +4203,7 @@ public Registry getRegistry() {
         return camelContextExtension.getRegistry();
     }
 
-    List<EndpointStrategy> getEndpointStrategies() {
+    Set<EndpointStrategy> getEndpointStrategies() {
         return endpointStrategies;
     }
 

core/camel-base-engine/src/main/java/org/apache/camel/impl/engine/DefaultCamelContextExtension.java

@@ -258,15 +258,17 @@ public Endpoint getEndpoint(NormalizedEndpointUri uri, Map<String, Object> param
 
     @Override
     public void registerEndpointCallback(EndpointStrategy strategy) {
-        if (!camelContext.getEndpointStrategies().contains(strategy)) {
-            // let it be invoked for already registered endpoints so it can
-            // catch-up.
-            camelContext.getEndpointStrategies().add(strategy);
+        // let it be invoked for already registered endpoints so it can
+        // catch-up.
+        if (camelContext.getEndpointStrategies().add(strategy)) {
             for (Endpoint endpoint : camelContext.getEndpoints()) {
-                Endpoint newEndpoint = strategy.registerEndpoint(endpoint.getEndpointUri(), endpoint);
+                Endpoint newEndpoint = strategy.registerEndpoint(endpoint.getEndpointUri(),
+                        endpoint);
                 if (newEndpoint != null) {
                     // put will replace existing endpoint with the new endpoint
-                    camelContext.getEndpointRegistry().put(camelContext.getEndpointKey(endpoint.getEndpointUri()), newEndpoint);
+                    camelContext.getEndpointRegistry()
+                            .put(camelContext.getEndpointKey(endpoint.getEndpointUri()),
+                                    newEndpoint);
                 }
             }
         }