[AMQ-9738] Remove requirement for network connector order in runtime configuration

activemq-runtime-config/src/main/java/org/apache/activemq/plugin/NetworkConnectorsProcessor.java

@@ -18,6 +18,9 @@
 
 import org.apache.activemq.schema.core.DtoNetworkConnector;
 
+import java.util.ArrayList;
+import java.util.List;
+
 public class NetworkConnectorsProcessor extends DefaultConfigurationProcessor {
 
     public NetworkConnectorsProcessor(RuntimeConfigurationBroker plugin, Class configurationClass) {
@@ -31,4 +34,32 @@ public ConfigurationProcessor findProcessor(Object o) {
         }
         return super.findProcessor(o);
     }
+
+    @Override
+    protected void applyModifications(List<Object> current, List<Object> modification) {
+        // Remove items not in modification
+        for (Object currentObj : new ArrayList<>(current)) {
+            if (!modification.contains(currentObj)) {
+                ConfigurationProcessor processor = findProcessor(currentObj);
+                if (processor != null) {
+                    processor.remove(currentObj);
+                } else {
+                    remove(currentObj);
+                }
+            }
+        }
+        // Add new items from modification
+        for (Object modObj : modification) {
+            if (!current.contains(modObj)) {
+                ConfigurationProcessor processor = findProcessor(modObj);
+                if (processor != null) {
+                    processor.addNew(modObj);
+                } else {
+                    addNew(modObj);
+                }
+            } else {
+                plugin.debug("Skipping unchanged network connector: " + modObj);
+            }
+        }
+    }
 }

activemq-runtime-config/src/test/java/org/apache/activemq/NetworkConnectorTest.java

@@ -110,11 +110,17 @@ public void testRemove() throws Exception {
         assertTrue("broker alive", brokerService.isStarted());
         assertEquals("correct network connectors", 2, brokerService.getNetworkConnectors().size());
 
-        NetworkConnector two = brokerService.getNetworkConnectors().get(1);
+        NetworkConnector two = null;
+        for (NetworkConnector nc : brokerService.getNetworkConnectors()) {
+            if ("two".equals(nc.getName())) {
+                two = nc;
+                break;
+            }
+        }
 
         applyNewConfig(brokerConfig, configurationSeed + "-one-nc", SLEEP);
 
-        assertTrue("expected mod on time", Wait.waitFor(new Wait.Condition() {
+        assertTrue("expected mod on time, but found " + brokerService.getNetworkConnectors().size() + " connectors", Wait.waitFor(new Wait.Condition() {
             @Override
             public boolean isSatisified() throws Exception {
                 return 1 == brokerService.getNetworkConnectors().size();
@@ -135,4 +141,23 @@ public boolean isSatisified() throws Exception {
         assertNotNull(brokerService.getManagementContext().getObjectInstance(
                 brokerService.createNetworkConnectorObjectName(remainingNetworkConnector)));
     }
+
+    @Test
+    public void testUnchangedNetworkConnector() throws Exception {
+        final String brokerConfig = configurationSeed + "-two-nc-broker";
+        applyNewConfig(brokerConfig, configurationSeed + "-two-nc");
+        startBroker(brokerConfig);
+        assertTrue("broker alive", brokerService.isStarted());
+        assertEquals("two network connectors", 2, brokerService.getNetworkConnectors().size());
+
+        // apply a config that changes the order only
+        applyNewConfig(brokerConfig, configurationSeed + "-two-b-nc", SLEEP);
+
+        assertTrue("expected mod on time", Wait.waitFor(new Wait.Condition() {
+            @Override
+            public boolean isSatisified() throws Exception {
+                return 2 == brokerService.getNetworkConnectors().size();
+            }
+        }));
+    }
 }

activemq-runtime-config/src/test/resources/org/apache/activemq/networkConnectorTest-two-b-nc.xml

@@ -0,0 +1,34 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+    Licensed to the Apache Software Foundation (ASF) under one or more
+    contributor license agreements.  See the NOTICE file distributed with
+    this work for additional information regarding copyright ownership.
+    The ASF licenses this file to You under the Apache License, Version 2.0
+    (the "License"); you may not use this file except in compliance with
+    the License.  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+    Unless required by applicable law or agreed to in writing, software
+    distributed under the License is distributed on an "AS IS" BASIS,
+    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+    See the License for the specific language governing permissions and
+    limitations under the License.
+-->
+<beans
+        xmlns="http://www.springframework.org/schema/beans"
+        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+        xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
+  http://activemq.apache.org/schema/core http://activemq.apache.org/schema/core/activemq-core.xsd">
+
+  <broker xmlns="http://activemq.apache.org/schema/core" start="false" persistent="false" >
+    <plugins>
+      <runtimeConfigurationPlugin checkPeriod="1000" />
+    </plugins>
+
+    <networkConnectors>
+      <networkConnector uri="static:(tcp://localhost:5555)" networkTTL="1" name="two"/>
+      <networkConnector uri="static:(tcp://localhost:5555)" networkTTL="1" name="one"/>
+    </networkConnectors>
+  </broker>
+</beans>