Added new Jandex based domain event registry

pom.xml

@@ -93,7 +93,7 @@
         <dependency>
             <groupId>org.fuin</groupId>
             <artifactId>units4j</artifactId>
-            <version>0.11.0</version>
+            <version>0.12.0-SNAPSHOT</version>
             <scope>test</scope>
         </dependency>
 
@@ -206,6 +206,20 @@
                 <artifactId>jacoco-maven-plugin</artifactId>
             </plugin>
 
+            <plugin>
+                <groupId>io.smallrye</groupId>
+                <artifactId>jandex-maven-plugin</artifactId>
+                <version>3.0.6</version>
+                <executions>
+                    <execution>
+                        <id>make-index</id>
+                        <goals>
+                            <goal>jandex</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+
         </plugins>
 
     </build>

src/main/java/org/fuin/cqrs4j/JandexDomainEventRegistry.java

@@ -0,0 +1,117 @@
+package org.fuin.cqrs4j;
+
+import jakarta.validation.constraints.NotNull;
+import org.fuin.ddd4j.ddd.DomainEvent;
+import org.fuin.ddd4j.ddd.JandexEntityIdFactory;
+import org.fuin.esc.api.*;
+import org.fuin.utils4j.JandexIndexFileReader;
+import org.fuin.utils4j.JandexUtils;
+import org.jboss.jandex.*;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.File;
+import java.lang.reflect.Modifier;
+import java.util.*;
+
+/**
+ * Registry that is built up by scanning for classes that are annotated with
+ * {@link HasSerializedDataTypeConstant} and implement {@link DomainEvent},
+ * but not {@link AggregateCommand}.
+ */
+public class JandexDomainEventRegistry implements SerializedDataTypeRegistry {
+
+    private static final Logger LOG = LoggerFactory.getLogger(JandexDomainEventRegistry.class);
+
+    private static final DotName COMMAND_INTERFACE = DotName.createSimple(Command.class);
+
+    private final SimpleSerializedDataTypeRegistry delegate;
+
+    private final List<File> classesDirs;
+
+    private final List<Class<?>> domainEventClasses;
+
+    /**
+     * Default constructor.
+     */
+    public JandexDomainEventRegistry() {
+        this(new File("target/classes"));
+    }
+
+    /**
+     * Constructor with classes directories. Most likely only used in tests.
+     *
+     * @param classesDirs Directories with class files.
+     */
+    public JandexDomainEventRegistry(final File... classesDirs) {
+        delegate = new SimpleSerializedDataTypeRegistry();
+        this.classesDirs = Arrays.asList(classesDirs);
+        domainEventClasses = scanForDomainEventClasses();
+        for (final Class<?> domainEventClass : domainEventClasses) {
+            delegate.add(serializedDataTypeConstant(domainEventClass), domainEventClass);
+        }
+    }
+
+    @Override
+    @NotNull
+    public Class<?> findClass(@NotNull SerializedDataType type) {
+        return delegate.findClass(type);
+    }
+
+    /**
+     * Returns a list of known {@link DomainEvent} classes.
+     *
+     * @return Domain event classes.
+     */
+    public List<Class<?>> getDomainEventClasses() {
+        return Collections.unmodifiableList(domainEventClasses);
+    }
+
+    private List<Class<?>> scanForDomainEventClasses() {
+        final List<IndexView> indexes = new ArrayList<>();
+        indexes.add(new JandexIndexFileReader.Builder().addDefaultResource().build().loadR());
+        indexes.add(indexClassesDirs());
+        return findDomainEventClasses(CompositeIndex.create(indexes));
+    }
+
+    private IndexView indexClassesDirs() {
+        final Indexer indexer = new Indexer();
+        final List<File> knownClassFiles = new ArrayList<>();
+        for (final File classesDir : classesDirs) {
+            JandexUtils.indexDir(indexer, knownClassFiles, classesDir);
+        }
+        return indexer.complete();
+    }
+
+    private static List<Class<?>> findDomainEventClasses(final IndexView index) {
+        List<Class<?>> classes = new ArrayList<>();
+        final Collection<ClassInfo> classInfos = index.getAllKnownImplementors(DotName.createSimple(DomainEvent.class));
+        for (final ClassInfo classInfo : classInfos) {
+            if (!Modifier.isAbstract(classInfo.flags())
+                    && !Modifier.isInterface(classInfo.flags())) {
+
+                final Class<?> clasz = JandexUtils.loadClass(classInfo.name());
+                if (!AggregateCommand.class.isAssignableFrom(clasz)) {
+                    boolean include = true;
+                    if (clasz.getAnnotation(HasSerializedDataTypeConstant.class) == null) {
+                        LOG.warn("Missing annotation @{} on {} class: {}", HasSerializedDataTypeConstant.class.getSimpleName(), DomainEvent.class.getSimpleName(), clasz.getName());
+                        include = false;
+                    }
+                    if (include) {
+                        classes.add(clasz);
+                        LOG.info("Added {} class to {}: {}", DomainEvent.class.getSimpleName(), JandexEntityIdFactory.class.getSimpleName(), clasz.getName());
+                    } else {
+                        LOG.debug("Ignored {} class: {}", DomainEvent.class.getSimpleName(), clasz.getName());
+                    }
+                }
+            }
+        }
+        return classes;
+    }
+
+    public SerializedDataType serializedDataTypeConstant(Class<?> domainEventClass) {
+        final HasSerializedDataTypeConstant annotation = domainEventClass.getAnnotation(HasSerializedDataTypeConstant.class);
+        return HasSerializedDataTypeConstantValidator.extractValue(domainEventClass, annotation.value());
+    }
+
+}

src/test/java/org/fuin/cqrs4j/ACreatedEvent.java

@@ -0,0 +1,56 @@
+/**
+ * Copyright (C) 2015 Michael Schnell. All rights reserved.
+ * http://www.fuin.org/
+ * <p>
+ * This library is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU Lesser General Public License as published by the Free
+ * Software Foundation; either version 3 of the License, or (at your option) any
+ * later version.
+ * <p>
+ * This library is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
+ * details.
+ * <p>
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library. If not, see http://www.gnu.org/licenses/.
+ */
+package org.fuin.cqrs4j;
+
+import org.fuin.ddd4j.ddd.AbstractDomainEvent;
+import org.fuin.ddd4j.ddd.EntityIdPath;
+import org.fuin.ddd4j.ddd.EventType;
+import org.fuin.esc.api.HasSerializedDataTypeConstant;
+import org.fuin.esc.api.SerializedDataType;
+import org.fuin.esc.api.TypeName;
+
+@HasSerializedDataTypeConstant
+public class ACreatedEvent extends AbstractDomainEvent<AId> {
+
+    private static final long serialVersionUID = 1L;
+
+    /** Unique name of the event. */
+    public static final TypeName TYPE = new TypeName("ACreatedEvent");
+
+    /** Unique name of the serialized event. */
+    public static final SerializedDataType SER_TYPE = new SerializedDataType(TYPE.asBaseType());
+
+    private static final EventType EVENT_TYPE = new EventType(TYPE.asBaseType());
+
+    private AId id;
+
+    public ACreatedEvent(final AId id) {
+        super(new EntityIdPath(id));
+        this.id = id;
+    }
+
+    public AId getId() {
+        return id;
+    }
+
+    @Override
+    public EventType getEventType() {
+        return EVENT_TYPE;
+    }
+
+}

src/test/java/org/fuin/cqrs4j/JandexDomainEventRegistryTest.java

@@ -0,0 +1,27 @@
+package org.fuin.cqrs4j;
+
+import org.junit.jupiter.api.Test;
+
+import java.io.File;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Test for the {@link JandexDomainEventRegistry} class.
+ */
+public class JandexDomainEventRegistryTest {
+
+    @Test
+    public void testCreate() {
+        final JandexDomainEventRegistry testee = new JandexDomainEventRegistry(new File("target/test-classes"));
+        assertThat(testee.getDomainEventClasses()).containsOnly(ACreatedEvent.class);
+    }
+
+    @Test
+    public void testFind() {
+        final JandexDomainEventRegistry testee = new JandexDomainEventRegistry(new File("target/test-classes"));
+        assertThat(testee.findClass(ACreatedEvent.SER_TYPE)).isEqualTo(ACreatedEvent.class);
+
+    }
+
+}