Java 11 migraiton: model-view-presenter

Author: anuragagarwal561994

model-view-presenter/src/main/java/com/iluwatar/model/view/presenter/App.java

@@ -44,9 +44,9 @@ public class App {
    * @param args command line args
    */
   public static void main(String[] args) {
-    FileLoader loader = new FileLoader();
-    FileSelectorJFrame frame = new FileSelectorJFrame();
-    FileSelectorPresenter presenter = new FileSelectorPresenter(frame);
+    var loader = new FileLoader();
+    var frame = new FileSelectorJFrame();
+    var presenter = new FileSelectorPresenter(frame);
     presenter.setLoader(loader);
     presenter.start();
   }

model-view-presenter/src/main/java/com/iluwatar/model/view/presenter/FileLoader.java

@@ -27,6 +27,7 @@
 import java.io.File;
 import java.io.FileReader;
 import java.io.Serializable;
+import java.util.stream.Collectors;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -59,18 +60,11 @@ public class FileLoader implements Serializable {
    * Loads the data of the file specified.
    */
   public String loadData() {
-    String dataFileName = this.fileName;
-    try (BufferedReader br = new BufferedReader(new FileReader(new File(dataFileName)))) {
-      StringBuilder sb = new StringBuilder();
-      String line;
-
-      while ((line = br.readLine()) != null) {
-        sb.append(line).append('\n');
-      }
-
+    var dataFileName = this.fileName;
+    try (var br = new BufferedReader(new FileReader(new File(dataFileName)))) {
+      var result = br.lines().collect(Collectors.joining("\n"));
       this.loaded = true;
-
-      return sb.toString();
+      return result;
     } catch (Exception e) {
       LOGGER.error("File {} does not exist", dataFileName);
     }

model-view-presenter/src/main/java/com/iluwatar/model/view/presenter/FileSelectorJFrame.java

@@ -48,37 +48,22 @@ public class FileSelectorJFrame extends JFrame implements FileSelectorView, Acti
   /**
    * The "OK" button for loading the file.
    */
-  private JButton ok;
+  private final JButton ok;
 
   /**
    * The cancel button.
    */
-  private JButton cancel;
-
-  /**
-   * The information label.
-   */
-  private JLabel info;
-
-  /**
-   * The contents label.
-   */
-  private JLabel contents;
+  private final JButton cancel;
 
   /**
    * The text field for giving the name of the file that we want to open.
    */
-  private JTextField input;
+  private final JTextField input;
 
   /**
    * A text area that will keep the contents of the file opened.
    */
-  private JTextArea area;
-
-  /**
-   * The panel that will hold our widgets.
-   */
-  private JPanel panel;
+  private final JTextArea area;
 
   /**
    * The Presenter component that the frame will interact with.
@@ -102,7 +87,7 @@ public FileSelectorJFrame() {
     /*
      * Add the panel.
      */
-    this.panel = new JPanel();
+    var panel = new JPanel();
     panel.setLayout(null);
     this.add(panel);
     panel.setBounds(0, 0, 500, 200);
@@ -111,48 +96,48 @@ public FileSelectorJFrame() {
     /*
      * Add the info label.
      */
-    this.info = new JLabel("File Name :");
-    this.panel.add(info);
+    var info = new JLabel("File Name :");
+    panel.add(info);
     info.setBounds(30, 10, 100, 30);
 
     /*
      * Add the contents label.
      */
-    this.contents = new JLabel("File contents :");
-    this.panel.add(contents);
-    this.contents.setBounds(30, 100, 120, 30);
+    var contents = new JLabel("File contents :");
+    panel.add(contents);
+    contents.setBounds(30, 100, 120, 30);
 
     /*
      * Add the text field.
      */
     this.input = new JTextField(100);
-    this.panel.add(input);
+    panel.add(input);
     this.input.setBounds(150, 15, 200, 20);
 
     /*
      * Add the text area.
      */
     this.area = new JTextArea(100, 100);
-    JScrollPane pane = new JScrollPane(area);
+    var pane = new JScrollPane(area);
     pane.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
     pane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED);
-    this.panel.add(pane);
+    panel.add(pane);
     this.area.setEditable(false);
     pane.setBounds(150, 100, 250, 80);
 
     /*
      * Add the OK button.
      */
     this.ok = new JButton("OK");
-    this.panel.add(ok);
+    panel.add(ok);
     this.ok.setBounds(250, 50, 100, 25);
     this.ok.addActionListener(this);
 
     /*
      * Add the cancel button.
      */
     this.cancel = new JButton("Cancel");
-    this.panel.add(this.cancel);
+    panel.add(this.cancel);
     this.cancel.setBounds(380, 50, 100, 25);
     this.cancel.addActionListener(this);
 

model-view-presenter/src/main/java/com/iluwatar/model/view/presenter/FileSelectorPresenter.java

@@ -41,7 +41,7 @@ public class FileSelectorPresenter implements Serializable {
   /**
    * The View component that the presenter interacts with.
    */
-  private FileSelectorView view;
+  private final FileSelectorView view;
 
   /**
    * The Model component that the presenter interacts with.
@@ -91,7 +91,7 @@ public void confirmed() {
     }
 
     if (loader.fileExists()) {
-      String data = loader.loadData();
+      var data = loader.loadData();
       view.displayData(data);
     } else {
       view.showMessage("The file specified does not exist.");

model-view-presenter/src/test/java/com/iluwatar/model/view/presenter/AppTest.java

@@ -26,16 +26,13 @@
 import org.junit.jupiter.api.Test;
 
 /**
- * 
  * Application test
- *
  */
 public class AppTest {
 
   @Test
   public void test() {
-    String[] args = {};
-    App.main(args);
+    App.main(new String[]{});
   }
 
 }

model-view-presenter/src/test/java/com/iluwatar/model/view/presenter/FileLoaderTest.java

@@ -23,10 +23,10 @@
 
 package com.iluwatar.model.view.presenter;
 
-import org.junit.jupiter.api.Test;
-
 import static org.junit.jupiter.api.Assertions.assertNull;
 
+import org.junit.jupiter.api.Test;
+
 /**
  * Date: 12/21/15 - 12:12 PM
  *
@@ -35,8 +35,8 @@
 public class FileLoaderTest {
 
   @Test
-  public void testLoadData() throws Exception {
-    final FileLoader fileLoader = new FileLoader();
+  public void testLoadData() {
+    final var fileLoader = new FileLoader();
     fileLoader.setFileName("non-existing-file");
     assertNull(fileLoader.loadData());
   }

model-view-presenter/src/test/java/com/iluwatar/model/view/presenter/FileSelectorPresenterTest.java

@@ -23,14 +23,14 @@
 
 package com.iluwatar.model.view.presenter;
 
-import org.junit.jupiter.api.BeforeEach;
-import org.junit.jupiter.api.Test;
-
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
 /**
  * This test case is responsible for testing our application by taking advantage of the
  * Model-View-Controller architectural pattern.
@@ -79,7 +79,7 @@ public void wiring() {
    */
   @Test
   public void updateFileNameToLoader() {
-    String expectedFile = "Stamatis";
+    var expectedFile = "Stamatis";
     stub.setFileName(expectedFile);
 
     presenter.start();