Grouping and adding up BigDecimals using Java Stream API

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• Why am i getting blank stage in JavaFX8, I think the maven is not loading the FXML files?

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  Pom.xml

          <project xmlns="http://maven.apache.org/POM/4.0.0"
                   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                   xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
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              <artifactId>QCap</artifactId>
              <version>1.0</version>
              <properties>
                  <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
                  <javafx.version>2.2</javafx.version>
              </properties>
              <build>
               <resources>
                  <resource>
                      <directory>src/main/resources</directory>
  
                  </resource>
              </resources>
                  <plugins>  
                     <plugin>
                          <groupId>org.apache.maven.plugins</groupId>
                          <artifactId>maven-compiler-plugin</artifactId>
                          <version>3.1</version>
                          <configuration>
                              <encoding>UTF-8</encoding>
                              <source>1.8</source>
                              <target>1.8</target>
                          <fork>true</fork>
                          <executable>C:\Program Files\Java\jdk1.8.0_191\bin\javac</executable>    
                          </configuration>
                      </plugin> 
                      <plugin>
                          <groupId>org.apache.maven.plugins</groupId>
                          <artifactId>maven-assembly-plugin</artifactId>
                          <executions>
                              <execution>
                                  <goals>
                                      <goal>attached</goal>
                                  </goals>
                                  <phase>package</phase>
                                  <configuration>
                                      <descriptorRefs>
                                          <descriptorRef>jar-with-dependencies</descriptorRef>
                                      </descriptorRefs>
                                      <archive>
                                          <manifest>
                                              <mainClass>com.objectiveware.qcap.QcapAppSingletonRunner</mainClass>
                                          </manifest>
                                      </archive>
                                  </configuration>
                              </execution>
                          </executions>
                      </plugin>
                   <!--    <plugin>
  
                          <groupId>org.apache.maven.plugins</groupId>
                          <artifactId>maven-dependency-plugin</artifactId>
                          <version>2.3</version>
                          <executions>
                              <execution>
                                  <id>copy-dependencies</id>
                                  <phase>package</phase>
                                  <configuration>
                                      <overWriteReleases>false</overWriteReleases>
                                      <overWriteSnapshots>false</overWriteSnapshots>
                                      <overWriteIfNewer>true</overWriteIfNewer>
                                  </configuration>
                                  <goals>
                                      <goal>copy-dependencies</goal>
                                  </goals>
                              </execution>
                          </executions>
                      </plugin> 
                      <plugin>
                          <groupId>org.apache.maven.plugins</groupId>
                          <artifactId>maven-jar-plugin</artifactId>
                          <configuration>
                              <archive>
                                  <manifestEntries>
                                      <JavaFX-Version>${javafx.version}+</JavaFX-Version>
                                      <Main-Class>com.objectiveware.qcap.StartCaptureTaskBar</Main-Class>
                                      <implementation-version>1.0</implementation-version>
                                      <JavaFX-Application-Class>com.objectiveware.qcap.StartCaptureTaskBar</JavaFX-Application-Class>
  
  
                                      <Class-Path>javafx-${javafx.version}.jar</Class-Path>
                                  </manifestEntries>
                                  <manifest>
                                      <addClasspath>true</addClasspath>
                                  </manifest>
                              </archive>
                          </configuration>
                      </plugin>
                      <plugin>
                          <groupId>org.apache.maven.plugins</groupId>
                          <artifactId>maven-antrun-plugin</artifactId>
                          <version>1.6</version>
                          <executions>
                              <execution>
                                  <phase>package</phase>
                                  <configuration>
                                      <target>
                                      <path id="qcappath">
                                              <pathelement path="${maven.plugin.classpath}"/>
                                              <fileset dir="${project.basedir}">
                                                  <include name="package/windows/QCap.ico"/>
  
                                              </fileset>
                                          </path>
  
                                          <taskdef name="jfxdeploy" classname="com.sun.javafx.tools.ant.DeployFXTask"
                                              classpathref="qcappath" />
  
  
                                          <jfxdeploy width="1024" height="768"
                                              outdir="${project.build.directory}/deploy" outfile="${project.build.finalName}"
                                              nativeBundles="exe" verbose="true">
                                              <info title="${project.name}" />
  
                                              <application name="${project.name}" mainClass="com.objectiveware.qcap.StartCaptureTaskBar" />
                                              <resources>
                                                  <fileset dir="${project.build.directory}" includes="*.jar" />
                                                  <fileset dir="${project.build.directory}/dependency"
                                                      includes="*.jar" />
                                              </resources>
  
                                              <platform javafx="${javafx.version}+">
                                                  <jvmarg value="-Xms512m" />
                                                  <jvmarg value="-Xmx1024m" />
                                              </platform>
                                          </jfxdeploy>
  
                                      </target>
                                  </configuration>
                                  <goals>
                                      <goal>run</goal>
                                  </goals>
                              </execution>
                          </executions>
                          <dependencies>
                              <dependency>
                                  <groupId>com.oracle</groupId>
                                  <artifactId>ant-javafx</artifactId>
                                  <version>${javafx.version}</version>
                                  <systemPath>${java.home}/../lib/ant-javafx.jar</systemPath>
                                  <scope>system</scope>
                              </dependency>
                              <dependency>
                                  <groupId>com.oracle</groupId>
                                  <artifactId>javafx</artifactId>
                                  <version>${javafx.version}</version>
                                  <systemPath>${java.home}/lib/ext/jfxrt.jar</systemPath>
                                  <scope>system</scope>
                              </dependency>
                          </dependencies>
                      </plugin> -->
                  </plugins>
                   </build>
              <dependencies>
                  <!-- https://mvnrepository.com/artifact/org.docx4j/docx4j -->
                  <dependency>
                      <groupId>org.docx4j</groupId>
                      <artifactId>docx4j</artifactId>
                      <version>6.0.1</version>
                  </dependency>
                  <!-- https://mvnrepository.com/artifact/commons-io/commons-io -->
                  <dependency>
                      <groupId>commons-io</groupId>
                      <artifactId>commons-io</artifactId>
                      <version>2.6</version>
                  </dependency>
                  <!-- https://mvnrepository.com/artifact/org.xhtmlrenderer/flying-saucer-pdf-openpdf -->
                  <dependency>
                      <groupId>org.xhtmlrenderer</groupId>
                      <artifactId>flying-saucer-pdf-openpdf</artifactId>
                      <version>9.1.16</version>
                  </dependency>
                  <!-- https://mvnrepository.com/artifact/com.jfoenix/jfoenix -->
                  <dependency>
                      <groupId>com.jfoenix</groupId>
                      <artifactId>jfoenix</artifactId>
                      <version>1.4.0</version>
                  </dependency>
                  <!-- https://mvnrepository.com/artifact/net.java.dev.jna/jna-platform -->
                  <dependency>
                      <groupId>net.java.dev.jna</groupId>
                      <artifactId>jna-platform</artifactId>
                      <version>4.0.0</version>
                  </dependency>
                  <!-- https://mvnrepository.com/artifact/net.java.dev.jna/jna -->
                  <dependency>
                      <groupId>net.java.dev.jna</groupId>
                      <artifactId>jna</artifactId>
                      <version>4.5.0</version>
                  </dependency>
                  <!-- https://mvnrepository.com/artifact/org.jsoup/jsoup -->
                  <dependency>
                      <groupId>org.jsoup</groupId>
                      <artifactId>jsoup</artifactId>
                      <version>1.8.3</version>
                  </dependency>
          <!-- https://mvnrepository.com/artifact/org.apache.maven/maven-plugin-api -->
          <dependency>
              <groupId>org.apache.maven</groupId>
              <artifactId>maven-plugin-api</artifactId>
              <version>3.1.0</version>
          </dependency>
                 <dependency>
                      <groupId>com.oracle</groupId>
                      <artifactId>javafx</artifactId>
                      <version>${javafx.version}</version>
                      <systemPath>${java.home}/lib/ext/jfxrt.jar</systemPath>
                      <scope>system</scope>
                  </dependency>
  
                  <dependency>
                      <groupId>org.apache.httpcomponents</groupId>
                      <artifactId>httpclient</artifactId>
                      <version>4.5.6</version>
                  </dependency>
                  <dependency>
                      <groupId>org.kordamp.bootstrapfx</groupId>
                      <artifactId>bootstrapfx-core</artifactId>
                      <version>0.2.4</version>
                  </dependency>
                  <dependency>
                  <groupId>org.openjfx</groupId>
                  <artifactId>javafx-controls</artifactId>
                  <version>11</version>
              </dependency>
              </dependencies>   
          </project>
  

  Java class

  package com.objectiveware.qcap;

  import static com.objectiveware.qcap.controllers.AppController.applicationScreenCapture;
  
  import java.awt.Desktop;
  import java.awt.SystemTray;
  import java.awt.TrayIcon;
  import java.io.IOException;
  import java.net.URI;
  import java.net.URISyntaxException;
  import java.util.Timer;
  import java.util.TimerTask;
  import javax.imageio.ImageIO;
  import javafx.application.Application;
  import javafx.scene.layout.BorderPane;
  
  import org.apache.commons.lang3.StringUtils;
  
  import com.objectiveware.qcap.controllers.LoginController;
  
  import javafx.application.Platform;
  import javafx.fxml.FXMLLoader;
  import javafx.scene.Parent;
  import javafx.scene.Scene;
  import javafx.stage.Stage;
  import javafx.stage.StageStyle;
  
  public class StartCaptureTaskBar 
  {
      private static Timer notificationTimer = new Timer();
      private static SystemTray tray;
      private static TrayIcon trayIcon;
  
      private Stage stage;
      private Stage settingsStage;
      private boolean authenticated;
      private Runnable exitCallback;
      private String userName;
      private String password;
      private boolean rememberChk;
      private boolean StartQCapAtLogin;
  
  
      public void createInstance(Stage stage, Runnable exitCallback) {
          // stores a reference to the stage.
          this.stage = stage;
          this.exitCallback = exitCallback;
          // instructs the javafx system not to exit implicitly when the last application
          // window is shut.
          Platform.setImplicitExit(false);
          // sets up the tray icon (using awt code run on the swing thread).
          javax.swing.SwingUtilities.invokeLater(this::addAppToTray);
          this.stage.setResizable(false);
          this.stage.initStyle(StageStyle.UTILITY);
          this.stage.setScene(createLoginContent());
          this.stage.setTitle("Login/Setting");
          this.stage.show();
      }
  
      public void open() {
          Platform.runLater(this::showStage);
      }
  
      /**
       * Callback method invoked to notify that a user has been authenticated. Will
       * show the main application screen.
       */
      public void authenticated(String sessionID) {
          authenticated = true;
          startMainPage();
      }
  
      public void startMainPage() {
          stage.setScene(createMainPageContent());
          stage.setTitle("Start Session");
          if (applicationScreenCapture != null && applicationScreenCapture.isStoped()) {
              applicationScreenCapture.restart();
              applicationScreenCapture.startHotKeysKeyboardListner();
              stage.hide();
          }
      }
  
      // TODO: will be implemented later, button will be added in main.fxml for logout
      public void logout() {
          authenticated = false;
          hideSettings();
          stage.setScene(createLoginContent("Session expired"));
          if (applicationScreenCapture != null) {
              applicationScreenCapture.pause();
              applicationScreenCapture.pauseHotKeys();
          }
          showStage();
      }
  
      private Scene createLoginContent() {
          return createLoginContent("");
      }
  
      private Scene createLoginContent(String error) {
          try {
  
              FXMLLoader loader = new FXMLLoader(getClass().getResource("/gui/login.fxml"));
              Parent root = loader.load();
              Scene scene = new Scene(root, 500, 400);
              //scene.getStylesheets().add("org/kordamp/bootstrapfx/bootstrapfx.css");
              scene.getStylesheets().add(getClass().getResource("/stylesheets/LoginTheme.css").toExternalForm());
              LoginController controller = loader.<LoginController>getController();
              if (StringUtils.isNotEmpty(error)) {
                  controller.setErrorMessage(error);
              }
              controller.initManager(this);
              return scene;
          } catch (IOException e) {
              e.printStackTrace();
          }
          return null;
      }
  
      private Scene createMainPageContent() {
  
          try {
              Parent root = FXMLLoader.load(getClass().getResource("/gui/main.fxml"));
              Scene scene = new Scene(root);
              return scene;
          } catch (IOException e) {
              e.printStackTrace();
          }
          return null;
      }
  
      /**
       * Sets up a system tray icon for the application.
       */
      private void addAppToTray() {
          try {
              java.awt.Toolkit.getDefaultToolkit();
  
              // app requires system tray support, just exit if there is no support.
              if (!java.awt.SystemTray.isSupported()) {
                  System.out.println("No system tray support, application exiting.");
                  Platform.exit();
              }
  
              tray = java.awt.SystemTray.getSystemTray();
  
              java.awt.Image image = ImageIO.read(getClass().getResource("/icons/screenshot.png"));
  
              trayIcon = new java.awt.TrayIcon(image);
  
              trayIcon.addActionListener(event -> Platform.runLater(this::showStage));
  
              // if the user selects the default menu item (which includes the app name),
              // show the main app stage.
              java.awt.MenuItem openItem = new java.awt.MenuItem("Start QCap");
              openItem.addActionListener(event -> Platform.runLater(this::showStage));
  
              // the convention for tray icons seems to be to set the default icon for opening
              // the application stage in a bold font.
              java.awt.Font defaultFont = java.awt.Font.decode(null);
              java.awt.Font boldFont = defaultFont.deriveFont(java.awt.Font.BOLD);
              openItem.setFont(boldFont);
  
              java.awt.MenuItem settingsItem = new java.awt.MenuItem("Settings");
              settingsItem.addActionListener(event -> Platform.runLater(this::showSettings));
  
              java.awt.MenuItem CheckForUpdatesItem = new java.awt.MenuItem("Check for Updates");
              CheckForUpdatesItem.addActionListener(event -> {
                  try {
                      Desktop.getDesktop().browse(new URI(Constants.CHECK_FOR_UPDATES_URL));
                  } catch (IOException | URISyntaxException e) {
                      e.printStackTrace();
                  }
              });
  
              java.awt.MenuItem helpItem = new java.awt.MenuItem("Help");
              helpItem.addActionListener(event -> {
                  try {
                      Desktop.getDesktop().browse(new URI(Constants.HELP_URL));
                  } catch (IOException | URISyntaxException e) {
                      e.printStackTrace();
                  }
              });
              java.awt.MenuItem aboutUSItem = new java.awt.MenuItem("About Us");
              aboutUSItem.addActionListener(event -> {
                  try {
                      Desktop.getDesktop().browse(new URI(Constants.ABOUT_US_URL));
                  } catch (IOException | URISyntaxException e) {
                      e.printStackTrace();
                  }
              });
  
              // to really exit the application, the user must go to the system tray icon
              // and select the exit option, this will shutdown JavaFX and remove the
              // tray icon (removing the tray icon will also shut down AWT).
              java.awt.MenuItem exitItem = new java.awt.MenuItem("Exit");
              exitItem.addActionListener(event -> exit());
  
              // setup the popup menu for the application.
              final java.awt.PopupMenu popup = new java.awt.PopupMenu();
              popup.add(openItem);
              popup.add(settingsItem);
              popup.addSeparator();
              popup.add(CheckForUpdatesItem);
              popup.add(helpItem);
              popup.add(aboutUSItem);
              popup.addSeparator();
              popup.add(exitItem);
              trayIcon.setPopupMenu(popup);
  
              // create a timer which periodically displays a notification message.
              notificationTimer.schedule(new TimerTask() {
                  @Override
                  public void run() {
                      javax.swing.SwingUtilities.invokeLater(() -> trayIcon.displayMessage("QCap Notifiction",
                              "QCap app is running ", java.awt.TrayIcon.MessageType.INFO));
                  }
              }, 5 * 60 * 1000, 5 * 60 * 1000);
  
              tray.add(trayIcon);
          } catch (java.awt.AWTException | IOException e) {
              System.out.println("Unable to init system tray");
              e.printStackTrace();
          }
      }
  
      void exit() {
          notificationTimer.cancel();
          Platform.exit();
          tray.remove(trayIcon);
          exitCallback.run();
          System.exit(0);
      }
  
      /**
       * Shows the application stage and ensures that it is brought ot the front of
       * all stages.
       */
      private void showStage() {
          if (stage != null) {
              stage.show();
              stage.toFront();
              stage.setIconified(false);
              stage.setAlwaysOnTop(true);
              stage.setAlwaysOnTop(false);
          }
      }
  
      private void showSettings() {
          if (isAuthenticated()) {
              if (settingsStage == null) {
                  settingsStage = new Stage();
              }
              settingsStage.setScene(createLoginContent());
              settingsStage.setTitle("Login/Settings");
              settingsStage.show();
              settingsStage.toFront();
              settingsStage.setIconified(false);
          }
      }
  
      public void hideSettings() {
          if (settingsStage != null) {
              settingsStage.hide();
          }
      }
  
      // public static void main(String[] args) throws IOException,
      // java.awt.AWTException {
      // launch(args);
      // }
  
      public void setStage(Stage stage) {
          this.stage = stage;
      }
  
      public boolean isAuthenticated() {
          return authenticated;
      }
  
      public String getUserName() {
          return userName;
      }
  
      public void setUserName(String userName) {
          this.userName = userName;
      }
  
      public String getPassword() {
          return password;
      }
  
      public void setPassword(String password) {
          this.password = password;
      }
  
  public boolean isRememberChk() {
      return rememberChk;
  }
  
  public void setRememberChk(boolean rememberChk) {
      this.rememberChk = rememberChk;
  }
  
  public boolean isStartQCapAtLogin() {
      return StartQCapAtLogin;
  }
  
  public void setStartQCapAtLogin(boolean startQCapAtLogin) {
      StartQCapAtLogin = startQCapAtLogin;
  }
  

  }
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  This should work, but it's a bit meh:

  Map<P,Optional<Q>> map = ...;
  Map<P,Q> map2 = map.entrySet()
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                    .collect(Collectors.toMap(e -> e.getKey(), e->e.getValue().get()));
  
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  I have a nested list of Long. for example:

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  Is there a way using streams to create a new list of items that are present in all the lists:

  List<Long> result = [2,3];
  
• Elegant way to overcome Unlikely argument type for equals(): Stream<String> seems to be unrelated to String

  I am looking for elegant way to overcome while comparing any Wrapper object to Stream.

  Github working link: https://github.com/vishwaratna/Unlikely-argument-type-for-equals-Stream-String-/commit/d803f77c923e81fe7531ecb467561ac785d7aca5

  Question in reference: Filtering keys from map to list attribute in java-8

  Recently i faced it while comparing member of List to a key of a Map. I know there are other ways to compare without doing what i am doing but i am looking for in general casting, if it is available.

  List<student> stulist = Arrays.asList(new student("1", "vishwa",null),
                                                new student("3", "Ravi",null),
                                                new student("2", "Ram",null));
  

  ---

          Map<String,String> map = new HashMap() {{
               put("1","20");
               put("2","30");
             }};
  

  ---

  System.out.println( stulist.stream()
                      .filter(s->s.getId()
                      .equals(map.entrySet()
                      .stream() 
                      .map(Map.Entry::getKey)))
                      .count());
  

  My code is compiling properly but the output is coming as "0", whereas i expect output as 2.

  I am sure it is due to type mismatch, but why the compiler is not throwing an error??

  Warning that i am getting: Unlikely argument type for equals(): Stream<String> seems to be unrelated to String