Java Tutorial/Swing/JProgressBar

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Содержание

A progress bar is used for lengthy tasks.

import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JProgressBar;
import javax.swing.Timer;
public class ProgressBar {
  public static void main(String[] args) {
    final Timer  timer;
    final JProgressBar progressBar = new JProgressBar();
    final JButton button = new JButton("Start");
    JFrame f = new JFrame();
    f.setLayout(new FlowLayout());
    f.add(progressBar);
    f.add(button);
    ActionListener updateProBar = new ActionListener() {
      public void actionPerformed(ActionEvent actionEvent) {
        int val = progressBar.getValue();
        if (val >= 100) {
        //  timer.stop();
          button.setText("End");
          return;
        }
        progressBar.setValue(++val);
      }
    };
    timer = new Timer(50, updateProBar);
    button.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        if (timer.isRunning()) {
          timer.stop();
          button.setText("Start");
        } else if (button.getText() != "End") {
          timer.start();
          button.setText("Stop");
        }
      }
    });
    f.pack();
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    f.setResizable(false);
    f.setLocationRelativeTo(null);
    f.setVisible(true);
  }
}





Creating a JProgressBar Component with an Unknown Maximum

import javax.swing.JProgressBar;
public class Main {
  public static void main(String[] argv) throws Exception {
    // Create a horizontal progress bar
    int min = 0;
    int max = 100;
    JProgressBar progress = new JProgressBar(min, max);
    // Play animation
    progress.setIndeterminate(true);
  }
}





Creating a modal progress dialog

import java.awt.BorderLayout;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JProgressBar;
public class Main {
  public static void main(String[] args) {
    JFrame parentFrame = new JFrame();
    parentFrame.setSize(500, 150);
    JLabel jl = new JLabel();
    jl.setText("Count : 0");
    parentFrame.add(BorderLayout.CENTER, jl);
    parentFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    parentFrame.setVisible(true);
    final JDialog dlg = new JDialog(parentFrame, "Progress Dialog", true);
    JProgressBar dpb = new JProgressBar(0, 500);
    dlg.add(BorderLayout.CENTER, dpb);
    dlg.add(BorderLayout.NORTH, new JLabel("Progress..."));
    dlg.setDefaultCloseOperation(JDialog.DO_NOTHING_ON_CLOSE);
    dlg.setSize(300, 75);
    dlg.setLocationRelativeTo(parentFrame);
    Thread t = new Thread(new Runnable() {
      public void run() {
        dlg.setVisible(true);
      }
    });
    t.start();
    for (int i = 0; i <= 500; i++) {
      jl.setText("Count : " + i);
      dpb.setValue(i);
      if(dpb.getValue() == 500){
        dlg.setVisible(false);
        System.exit(0);
 
      }
      try {
        Thread.sleep(25);
      } catch (InterruptedException e) {
        e.printStackTrace();
      }
    }
    dlg.setVisible(true);
  }
}





Customizing JProgressBar Look and Feel

Property StringObject TypeProgressBar.backgroundColorProgressBar.borderBorderProgressBar.cellLengthIntegerProgressBar.cellSpacingIntegerProgressBar.cycleTimeIntegerProgressBar.fontFontProgressBar.foregroundColorProgressBar.highlightColorProgressBar.horizontalSizeDimensionProgressBar.repaintIntervalIntegerProgressBar.selectionBackgroundColorProgressBar.selectionForegroundColorProgressBar.shadowColorProgressBar.verticalSizeDimensionProgressBarUIString


Displaying the Percentage Done on a JProgressBar Component

import javax.swing.JProgressBar;
public class Main {
  public static void main(String[] argv) throws Exception {
    int minimum = 0;
    int maximum = 100;
    JProgressBar progress = new JProgressBar(minimum, maximum);
    // Overlay a string showing the percentage done
    progress.setStringPainted(true);
  }
}





Getting and Setting the Values of a JProgressBar Component

import javax.swing.JProgressBar;
public class Main {
  public static void main(String[] argv) throws Exception {
    int minimum = 0;
    int maximum = 100;
    JProgressBar progress = new JProgressBar(minimum, maximum);
    // Get the current value
    int value = progress.getValue();
    // Get the minimum value
    int min = progress.getMinimum();
    // Get the maximum value
    int max = progress.getMaximum();
    // Change the minimum value
    int newMin = 0;
    progress.setMinimum(newMin);
    // Change the maximum value
    int newMax = 256;
    progress.setMaximum(newMax);
    // Set the value; the new value will be forced into the bar"s range
    int newValue = 33;
    progress.setValue(newValue);
  }
}





Handling JProgressBar Events: notification of data model changes through a ChangeListener

import java.awt.BorderLayout;
import javax.swing.JFrame;
import javax.swing.JProgressBar;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
class BoundedChangeListener implements ChangeListener {
  public void stateChanged(ChangeEvent changeEvent) {
    Object source = changeEvent.getSource();
    if (source instanceof JProgressBar) {
      JProgressBar theJProgressBar = (JProgressBar) source;
      System.out.println("ProgressBar changed: " + theJProgressBar.getValue());
    } else {
      System.out.println("Something changed: " + source);
    }
  }
}
public class ProgressBarStepBoundedChangeListener {
  public static void main(String args[]) throws Exception {
    JFrame frame = new JFrame("Stepping Progress");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    final JProgressBar aJProgressBar = new JProgressBar(JProgressBar.VERTICAL);
    aJProgressBar.setStringPainted(true);
    aJProgressBar.addChangeListener(new BoundedChangeListener());
    for (int i = 0; i < 10; i++) {
      aJProgressBar.setValue(i++);
      Thread.sleep(100);
    }
    frame.add(aJProgressBar, BorderLayout.NORTH);
    frame.setSize(300, 200);
    frame.setVisible(true);
  }
}





JProgressBar

There are five different constructors for JProgressBar:



public JProgressBar()
JProgressBar aJProgressBar = new JProgressBar();
public JProgressBar(int orientation)
JProgressBar aJProgressBar = new JProgressBar(JProgressBar.VERTICAL);
JProgressBar bJProgressBar = new JProgressBar(JProgressBar.HORIZONTAL);
public JProgressBar(int minimum, int maximum)
JProgressBar aJProgressBar = new JProgressBar(0, 500);
public JProgressBar(int orientation, int minimum, int maximum)
JProgressBar aJProgressBar = new JProgressBar(JProgressBar.VERTICAL, 0, 1000);
public JProgressBar(BoundedRangeModel model)
// Data model, initial value 0, range 0-250, and extent of 0
DefaultBoundedRangeModel model = new DefaultBoundedRangeModel(0, 0, 0, 250);
JProgressBar aJProgressBar = new JProgressBar(model);





Labeling a JProgressBar

To display the percentage completed [100 X (value-minimum)/(maximum-minimum)], call the public void setStringPainted(boolean newValue) method with a parameter of true.



import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JProgressBar;
public class ProgressBarStep {
  static class BarThread extends Thread {
    private static int DELAY = 500;
    JProgressBar progressBar;
    public BarThread(JProgressBar bar) {
      progressBar = bar;
    }
    public void run() {
      int minimum = progressBar.getMinimum();
      int maximum = progressBar.getMaximum();
      for (int i = minimum; i < maximum; i++) {
        try {
          int value = progressBar.getValue();
          progressBar.setValue(value + 1);
          Thread.sleep(DELAY);
        } catch (InterruptedException ignoredException) {
        }
      }
    }
  }
  public static void main(String args[]) {
    JFrame frame = new JFrame("Stepping Progress");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    final JProgressBar aJProgressBar = new JProgressBar(0, 50);
    aJProgressBar.setStringPainted(true);
    final JButton aJButton = new JButton("Start");
    ActionListener actionListener = new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        aJButton.setEnabled(false);
        Thread stepper = new BarThread(aJProgressBar);
        stepper.start();
      }
    };
    aJButton.addActionListener(actionListener);
    frame.add(aJProgressBar, BorderLayout.NORTH);
    frame.add(aJButton, BorderLayout.SOUTH);
    frame.setSize(300, 200);
    frame.setVisible(true);
  }
}





Listening for Value Changes in a JProgressBar Component

import javax.swing.JProgressBar;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
public class Main {
  public static void main(String[] argv) throws Exception {
    int minimum = 0;
    int maximum = 100;
    JProgressBar progress = new JProgressBar(minimum, maximum);
    progress.addChangeListener(new ChangeListener() {
      public void stateChanged(ChangeEvent evt) {
        JProgressBar comp = (JProgressBar) evt.getSource();
        int value = comp.getValue();
        int min = comp.getMinimum();
        int max = comp.getMaximum();
      }
    });
  }
}





ProgressBar and Task

/*
 * Copyright (c) 1995 - 2008 Sun Microsystems, Inc.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 *   - Neither the name of Sun Microsystems nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
import java.awt.BorderLayout;
import java.awt.Insets;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.util.Random;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JProgressBar;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.SwingWorker;
public class ProgressBarDemo2 extends JPanel implements ActionListener,
    PropertyChangeListener {
  private JProgressBar progressBar;
  private JButton startButton;
  private JTextArea taskOutput;
  private Task task;
  class Task extends SwingWorker<Void, Void> {
    /*
     * Main task. Executed in background thread.
     */
    @Override
    public Void doInBackground() {
      Random random = new Random();
      int progress = 0;
      // Initialize progress property.
      setProgress(0);
      // Sleep for at least one second to simulate "startup".
      try {
        Thread.sleep(1000 + random.nextInt(2000));
      } catch (InterruptedException ignore) {
      }
      while (progress < 100) {
        // Sleep for up to one second.
        try {
          Thread.sleep(random.nextInt(1000));
        } catch (InterruptedException ignore) {
        }
        // Make random progress.
        progress += random.nextInt(10);
        setProgress(Math.min(progress, 100));
      }
      return null;
    }
    /*
     * Executed in event dispatch thread
     */
    public void done() {
      Toolkit.getDefaultToolkit().beep();
      startButton.setEnabled(true);
      taskOutput.append("Done!\n");
    }
  }
  public ProgressBarDemo2() {
    super(new BorderLayout());
    // Create the demo"s UI.
    startButton = new JButton("Start");
    startButton.setActionCommand("start");
    startButton.addActionListener(this);
    progressBar = new JProgressBar(0, 100);
    progressBar.setValue(0);
    // Call setStringPainted now so that the progress bar height
    // stays the same whether or not the string is shown.
    progressBar.setStringPainted(true);
    taskOutput = new JTextArea(5, 20);
    taskOutput.setMargin(new Insets(5, 5, 5, 5));
    taskOutput.setEditable(false);
    JPanel panel = new JPanel();
    panel.add(startButton);
    panel.add(progressBar);
    add(panel, BorderLayout.PAGE_START);
    add(new JScrollPane(taskOutput), BorderLayout.CENTER);
    setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
  }
  /**
   * Invoked when the user presses the start button.
   */
  public void actionPerformed(ActionEvent evt) {
    progressBar.setIndeterminate(true);
    startButton.setEnabled(false);
    // Instances of javax.swing.SwingWorker are not reusuable, so
    // we create new instances as needed.
    task = new Task();
    task.addPropertyChangeListener(this);
    task.execute();
  }
  /**
   * Invoked when task"s progress property changes.
   */
  public void propertyChange(PropertyChangeEvent evt) {
    if ("progress" == evt.getPropertyName()) {
      int progress = (Integer) evt.getNewValue();
      progressBar.setIndeterminate(false);
      progressBar.setValue(progress);
      taskOutput.append(String.format("Completed %d%% of task.\n", progress));
    }
  }
  /**
   * Create the GUI and show it. As with all GUI code, this must run on the
   * event-dispatching thread.
   */
  private static void createAndShowGUI() {
    // Create and set up the window.
    JFrame frame = new JFrame("ProgressBarDemo2");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    // Create and set up the content pane.
    JComponent newContentPane = new ProgressBarDemo2();
    newContentPane.setOpaque(true); // content panes must be opaque
    frame.setContentPane(newContentPane);
    // Display the window.
    frame.pack();
    frame.setVisible(true);
  }
  public static void main(String[] args) {
    // Schedule a job for the event-dispatching thread:
    // creating and showing this application"s GUI.
    javax.swing.SwingUtilities.invokeLater(new Runnable() {
      public void run() {
        createAndShowGUI();
      }
    });
  }
}





Set all the values at once by using the model

import javax.swing.JProgressBar;
public class Main {
  public static void main(String[] argv) throws Exception {
    int minimum = 0;
    int maximum = 100;
    JProgressBar progress = new JProgressBar(minimum, maximum);
    int newValue = 10;
    int newMin = 0;
    int newMax = 100;
    progress.getModel().setRangeProperties(newValue, 0, newMin, newMax, false);
  }
}





SwingWorker and ProgressBar

/*
 * Copyright (c) 1995 - 2008 Sun Microsystems, Inc.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 *   - Neither the name of Sun Microsystems nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
import java.awt.BorderLayout;
import java.awt.Cursor;
import java.awt.Insets;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.util.Random;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JProgressBar;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.SwingWorker;
public class ProgressBarDemo extends JPanel implements ActionListener,
    PropertyChangeListener {
  private JProgressBar progressBar;
  private JButton startButton;
  private JTextArea taskOutput;
  private Task task;
  class Task extends SwingWorker<Void, Void> {
    /*
     * Main task. Executed in background thread.
     */
    @Override
    public Void doInBackground() {
      Random random = new Random();
      int progress = 0;
      // Initialize progress property.
      setProgress(0);
      while (progress < 100) {
        // Sleep for up to one second.
        try {
          Thread.sleep(random.nextInt(1000));
        } catch (InterruptedException ignore) {
        }
        // Make random progress.
        progress += random.nextInt(10);
        setProgress(Math.min(progress, 100));
      }
      return null;
    }
    /*
     * Executed in event dispatching thread
     */
    @Override
    public void done() {
      Toolkit.getDefaultToolkit().beep();
      startButton.setEnabled(true);
      setCursor(null); // turn off the wait cursor
      taskOutput.append("Done!\n");
    }
  }
  public ProgressBarDemo() {
    super(new BorderLayout());
    // Create the demo"s UI.
    startButton = new JButton("Start");
    startButton.setActionCommand("start");
    startButton.addActionListener(this);
    progressBar = new JProgressBar(0, 100);
    progressBar.setValue(0);
    progressBar.setStringPainted(true);
    taskOutput = new JTextArea(5, 20);
    taskOutput.setMargin(new Insets(5, 5, 5, 5));
    taskOutput.setEditable(false);
    JPanel panel = new JPanel();
    panel.add(startButton);
    panel.add(progressBar);
    add(panel, BorderLayout.PAGE_START);
    add(new JScrollPane(taskOutput), BorderLayout.CENTER);
    setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
  }
  /**
   * Invoked when the user presses the start button.
   */
  public void actionPerformed(ActionEvent evt) {
    startButton.setEnabled(false);
    setCursor(Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR));
    // Instances of javax.swing.SwingWorker are not reusuable, so
    // we create new instances as needed.
    task = new Task();
    task.addPropertyChangeListener(this);
    task.execute();
  }
  /**
   * Invoked when task"s progress property changes.
   */
  public void propertyChange(PropertyChangeEvent evt) {
    if ("progress" == evt.getPropertyName()) {
      int progress = (Integer) evt.getNewValue();
      progressBar.setValue(progress);
      taskOutput.append(String.format("Completed %d%% of task.\n", task
          .getProgress()));
    }
  }
  /**
   * Create the GUI and show it. As with all GUI code, this must run on the
   * event-dispatching thread.
   */
  private static void createAndShowGUI() {
    // Create and set up the window.
    JFrame frame = new JFrame("ProgressBarDemo");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    // Create and set up the content pane.
    JComponent newContentPane = new ProgressBarDemo();
    newContentPane.setOpaque(true); // content panes must be opaque
    frame.setContentPane(newContentPane);
    // Display the window.
    frame.pack();
    frame.setVisible(true);
  }
  public static void main(String[] args) {
    // Schedule a job for the event-dispatching thread:
    // creating and showing this application"s GUI.
    javax.swing.SwingUtilities.invokeLater(new Runnable() {
      public void run() {
        createAndShowGUI();
      }
    });
  }
}





Using an Indeterminate JProgressBar

Indeterminate mode: Progress bar bounces back and forth from side to side



import java.awt.BorderLayout;
import javax.swing.JFrame;
import javax.swing.JProgressBar;
public class ProgressBarStepIndeterminate {
  public static void main(String args[]) {
    JFrame frame = new JFrame("Stepping Progress");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    final JProgressBar aJProgressBar = new JProgressBar(JProgressBar.VERTICAL);
    aJProgressBar.setStringPainted(true);
    aJProgressBar.setIndeterminate(true);
    frame.add(aJProgressBar, BorderLayout.NORTH);
    frame.setSize(300, 200);
    frame.setVisible(true);
  }
}





Virtical JProgressBar

To change the label to a fixed string, call the public void setString(String newValue) method and setStringPainted(true). On a vertical progress bar, the string is drawn rotated, so a longer string will fit better.



import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JProgressBar;
class BarThread extends Thread {
  private static int DELAY = 500;
  JProgressBar progressBar;
  public BarThread(JProgressBar bar) {
    progressBar = bar;
  }
  public void run() {
    int minimum = progressBar.getMinimum();
    int maximum = progressBar.getMaximum();
    for (int i = minimum; i < maximum; i++) {
      try {
        int value = progressBar.getValue();
        progressBar.setValue(value + 1);
        Thread.sleep(DELAY);
      } catch (InterruptedException ignoredException) {
      }
    }
  }
}
public class ProgressBarStep {
  public static void main(String args[]) {
    JFrame frame = new JFrame("Stepping Progress");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    final JProgressBar aJProgressBar = new JProgressBar(JProgressBar.VERTICAL);
    aJProgressBar.setStringPainted(true);
    final JButton aJButton = new JButton("Start");
    ActionListener actionListener = new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        aJButton.setEnabled(false);
        Thread stepper = new BarThread(aJProgressBar);
        stepper.start();
      }
    };
    aJButton.addActionListener(actionListener);
    frame.add(aJProgressBar, BorderLayout.NORTH);
    frame.add(aJButton, BorderLayout.SOUTH);
    frame.setSize(300, 200);
    frame.setVisible(true);
  }
}


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