Java Data Structure How to - Make QuickSort graphic

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Question

We would like to know how to make QuickSort graphic.

Answer

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Graphics;
/*from w  w  w .  java2 s.c o m*/
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;

public class Main {
  public static void main(String[] args) {
    JFrame f = new JFrame();
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    MyModel myArrayClass = new MyModel(25);

    MyView panel = new MyView(myArrayClass);
    myArrayClass.myView = panel;

    JButton sortButton = new JButton("Sort");
    sortButton.addActionListener(e -> performSorting(myArrayClass));
    f.getContentPane().add(sortButton, BorderLayout.NORTH);
    f.getContentPane().add(panel, BorderLayout.CENTER);
    f.setSize(400, 400);
    f.setVisible(true);
  }

   static void performSorting( MyModel myArrayClass) {
    Thread thread = new Thread(()-> {
        myArrayClass.QuickSort(0, myArrayClass.arraySize - 1);
        System.out.println("Done");
    });
    thread.start();
  }
}
class MyView extends JPanel {
  MyModel myModel;
  public MyView(MyModel myArrayClass) {
    this.myModel = myArrayClass;
  }
  @Override
  protected void paintComponent(Graphics g) {
    super.paintComponent(g);
    g.setColor(Color.WHITE);
    int size = myModel.arraySize;
    int barWidth = getWidth() / size;
    for (int i = 0; i < size; i++) {
      int value = myModel.myArray[i];
      int x = i * barWidth;
      int y = getHeight() - value;
      g.fillRect(x + 1, y, barWidth - 2, value);
    }
  }
}

class MyModel {
  int myArray[];
  int arraySize;
  int res;
  MyView myView;
  public MyModel(int size) {
    arraySize = size;
    myArray = new int[arraySize];
    for (int i = 0; i < arraySize; i++) {
      myArray[i] = (int) (Math.random() * 99) + 1;
    }
  }

  public void QuickSort(int Left, int Right) {
    if (Right - Left <= 0) {
      return;
    } else {
      int Pivot = myArray[Right];
      Partitioning(Left, Right, Pivot);
      int PivotValue = res;
      QuickSort(Left, PivotValue - 1);
      QuickSort(PivotValue + 1, Right);
    }
  }

  public void Partitioning(int Left, int Right, int Pivot) {
    int LeftP = Left - 1;
    int RightP = Right;
    while (true) {
      while (LeftP < Right && myArray[++LeftP] < Pivot) {
      }
      while (RightP > 0 && myArray[--RightP] > Pivot) {
      }
      if (RightP <= LeftP) {
        SwapValues(LeftP, Right);
        res = LeftP;
        break;
      } else {
        SwapValues(LeftP, RightP);
        break;
      }
    }
  }

  private void SwapValues(int LeftP, int RightP) {
    int aux = myArray[LeftP];
    myArray[LeftP] = myArray[RightP];
    myArray[RightP] = aux;

    try {
      Thread.sleep(150);
    } catch (Exception e) {
      Thread.currentThread().interrupt();
    }
    myView.repaint();
  }
}

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