[small]Adding first metadata controller test

src/main/java/com/josdem/jmetadata/controller/MetadataController.java

@@ -29,6 +29,7 @@
 import java.util.Collections;
 import java.util.List;
 import java.util.Properties;
+import javax.annotation.PostConstruct;
 import javax.swing.JFileChooser;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
@@ -49,12 +50,17 @@ public class MetadataController {
   private final Properties properties;
   private final MetadataService metadataService;
   private final ControlEngineConfigurator configurator;
+  protected JFileChooser fileChooser;
 
   private List<Metadata> metadataList;
 
+  @PostConstruct
+  void setup() {
+    fileChooser = new JFileChooser();
+  }
+
   @ActionMethod(Actions.GET_METADATA)
   public void getMetadata() {
-    var fileChooser = new JFileChooser();
     fileChooser.setFileSelectionMode(JFileChooser.FILES_AND_DIRECTORIES);
     var selection = fileChooser.showOpenDialog(null);
     if (selection == JFileChooser.APPROVE_OPTION) {

src/test/java/com/josdem/jmetadata/controller/MetadataControllerTest.java

@@ -0,0 +1,75 @@
+/*
+   Copyright 2025 Jose Morales [email protected]
+
+   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 com.josdem.jmetadata.controller;
+
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import com.josdem.jmetadata.event.Events;
+import com.josdem.jmetadata.service.MetadataService;
+import java.io.File;
+import java.util.Collections;
+import java.util.Properties;
+import javax.swing.*;
+import lombok.extern.slf4j.Slf4j;
+import org.asmatron.messengine.ControlEngine;
+import org.asmatron.messengine.engines.support.ControlEngineConfigurator;
+import org.asmatron.messengine.event.ValueEvent;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.TestInfo;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+
+@Slf4j
+class MetadataControllerTest {
+
+  private MetadataController metadataController;
+
+  @Mock private Properties properties;
+  @Mock private MetadataService metadataService;
+  @Mock private ControlEngineConfigurator configurator;
+  @Mock private ControlEngine controlEngine;
+  @Mock private JFileChooser fileChooser;
+  @Mock private File file;
+
+  @BeforeEach
+  void setup() {
+    MockitoAnnotations.openMocks(this);
+    metadataController = new MetadataController(properties, metadataService, configurator);
+    metadataController.fileChooser = fileChooser;
+  }
+
+  @Test
+  @DisplayName("informing user selected an empty directory")
+  void shouldGetMetadata(TestInfo testInfo) throws Exception {
+    log.info(testInfo.getDisplayName());
+    when(fileChooser.showOpenDialog(null)).thenReturn(JFileChooser.APPROVE_OPTION);
+    when(fileChooser.getSelectedFile()).thenReturn(file);
+    when(file.exists()).thenReturn(true);
+    when(configurator.getControlEngine()).thenReturn(controlEngine);
+    when(metadataService.extractMetadata(file)).thenReturn(Collections.emptyList());
+
+    metadataController.getMetadata();
+
+    verify(fileChooser).setFileSelectionMode(JFileChooser.FILES_AND_DIRECTORIES);
+    verify(controlEngine)
+        .fireEvent(Events.DIRECTORY_SELECTED, new ValueEvent<>(file.getAbsolutePath()));
+    verify(controlEngine).fireEvent(Events.DIRECTORY_EMPTY);
+  }
+}