implement aggregate lifecycle helper methods, fix #71

Author: zambrovski

kotlin/src/main/kotlin/org/axonframework/extensions/kotlin/AggregateLifecycleExtensions.kt

@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2010-2020. Axon Framework
+ *
+ * Licensed 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.
+ */
+
+package org.axonframework.extensions.kotlin
+
+import org.axonframework.messaging.MetaData
+import org.axonframework.modelling.command.Aggregate
+import org.axonframework.modelling.command.AggregateLifecycle
+import org.axonframework.modelling.command.ApplyMore
+
+/**
+ * Alias for [AggregateLifecycle.apply] method.
+ * @param payload payload of the event message to be applied.
+ * @return fluent instance to apply more.
+ */
+fun applyEvent(payload: Any): ApplyMore = AggregateLifecycle.apply(payload)
+
+/**
+ * Alias for [AggregateLifecycle.apply] method.
+ * @param payload payload of the event message to be applied.
+ * @param metaData metadata to be included into the event message.
+ * @return fluent instance to apply more.
+ */
+fun applyEvent(payload: Any, metaData: MetaData): ApplyMore = AggregateLifecycle.apply(payload, metaData)
+
+/**
+ * Create new aggregate instance.
+ * @param [T] aggregate type.
+ * @param factoryMethod factory method.
+ */
+inline fun <reified T : Any> createNew(noinline factoryMethod: () -> T): Aggregate<T> = AggregateLifecycle.createNew(T::class.java, factoryMethod)