Introduces dedicated factory to perform object's initialisation

core/src/main/java/com/opensymphony/xwork2/inject/InitializableFactory.java

@@ -0,0 +1,56 @@
+/*
+ * 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.
+ */
+package com.opensymphony.xwork2.inject;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
+class InitializableFactory<T> implements InternalFactory<T> {
+
+    private static final Logger LOG = LogManager.getLogger(InitializableFactory.class);
+
+    private InternalFactory<T> internalFactory;
+
+    private InitializableFactory(InternalFactory<T> internalFactory) {
+        this.internalFactory = internalFactory;
+    }
+
+    public static InternalFactory<?> wrapIfNeeded(InternalFactory<?> internalFactory) {
+        if (Initializable.class.isAssignableFrom(internalFactory.type())) {
+            return new InitializableFactory<>(internalFactory);
+        }
+        return internalFactory;
+    }
+
+    @Override
+    public T create(InternalContext context) {
+        T instance = internalFactory.create(context);
+        if (Initializable.class.isAssignableFrom(instance.getClass())) {
+            Initializable.class.cast(instance).init();
+        } else {
+            LOG.error("Class {} is not marked as {}!", internalFactory.getClass().getName(), Initializable.class.getName());
+        }
+        return instance;
+    }
+
+    @Override
+    public Class<? extends T> type() {
+        return internalFactory.type();
+    }
+}