Zinsrechner

import java.awt.Color;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.Insets;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.math.BigDecimal;
import java.text.NumberFormat;
import java.util.Locale;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTextField;
import javax.swing.SwingConstants;
import javax.swing.WindowConstants;

/**
 *
 * Beschreibung
 *
 * @version 1.0 (Alpha) vom 08.05.2021
 * @author DPU
 *
 */

public class ZinsrechnerDPU extends JFrame {

  private JLabel lZinsrechnerDPU = new JLabel();
  private JLabel labelCapital = new JLabel();
  private JTextField fieldCapital = new JTextField();
  private JLabel labelRunTime = new JLabel();
  private JTextField fieldRunTime = new JTextField();
  private JLabel labelInterestRate = new JLabel();
  private JTextField fieldInterestRate = new JTextField();
  private JButton bBerechnung = new JButton();
  private JLabel labelTotalCaptital = new JLabel();
  private JTextField fieldTotalCapital = new JTextField();
  private JLabel labelTotalInterestRate = new JLabel();
  private JTextField fieldTotalInterestRate = new JTextField();


  public ZinsrechnerDPU() {

    super();
    setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
    int frameWidth = 756;
    int frameHeight = 480;
    setSize(frameWidth, frameHeight);
    Dimension d = Toolkit.getDefaultToolkit().getScreenSize();
    int x = (d.width - getSize().width) / 2;
    int y = (d.height - getSize().height) / 2;
    setLocation(x, y);
    setTitle("Zinsrechner DPU");
    setResizable(false);
    Container cp = getContentPane();
    cp.setLayout(null);


    cp.setBackground(Color.GRAY);
    lZinsrechnerDPU.setBounds(10, 8, 700, 20);
    lZinsrechnerDPU.setText("Zinsrechner -DPU-");
    lZinsrechnerDPU.setHorizontalAlignment(SwingConstants.CENTER);
    cp.add(lZinsrechnerDPU);
    labelCapital.setBounds(40, 60, 110, 20);
    labelCapital.setText("Kapital");
    labelCapital.setToolTipText("Trennzeichen .");
    labelCapital.setHorizontalAlignment(SwingConstants.CENTER);
    labelCapital.setVerticalAlignment(SwingConstants.CENTER);
    cp.add(labelCapital);
    fieldCapital.setBounds(40, 85, 150, 20);
    fieldCapital.setSelectionEnd(0);
    fieldCapital.setHorizontalAlignment(SwingConstants.CENTER);
    cp.add(fieldCapital);
    labelRunTime.setBounds(40, 125, 110, 20);
    labelRunTime.setText("Laufzeit");
    labelRunTime.setHorizontalAlignment(SwingConstants.CENTER);
    cp.add(labelRunTime);
    fieldRunTime.setBounds(40, 150, 150, 20);
    fieldRunTime.setHorizontalAlignment(SwingConstants.CENTER);
    cp.add(fieldRunTime);
    labelInterestRate.setBounds(40, 190, 110, 20);
    labelInterestRate.setText("Zinssatz");
    labelInterestRate.setHorizontalAlignment(SwingConstants.CENTER);
    cp.add(labelInterestRate);
    fieldInterestRate.setBounds(40, 215, 150, 20);
    fieldInterestRate.setHorizontalAlignment(SwingConstants.CENTER);
    cp.add(fieldInterestRate);
    bBerechnung.setBounds(70, 290, 100, 25);
    bBerechnung.setText("Berechnung");
    bBerechnung.setMargin(new Insets(2, 2, 2, 2));
    bBerechnung.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
            NumberFormat cf = NumberFormat.getCurrencyInstance(Locale.GERMANY);

            BigDecimal capital = new BigDecimal(fieldCapital.getText());
            System.out.println(capital);
            BigDecimal runTime = new BigDecimal(fieldRunTime.getText());
            System.out.println(runTime);
            BigDecimal interestRate = new BigDecimal(fieldInterestRate.getText());
            System.out.println(interestRate);

            BigDecimal totalInterrestRate =
                    capital.multiply(interestRate)
                    .multiply(runTime)
                    .divide(BigDecimal.valueOf(12*100));

            System.out.println(cf.format(totalInterrestRate));

            BigDecimal totalCapital =
                    capital.multiply(interestRate)
                    .multiply(runTime)
                    .divide(BigDecimal.valueOf(12*100))
                    .add(capital);

            System.out.println(cf.format(totalCapital));

            String totalCapitalString = String.valueOf(cf.format(totalCapital));

            fieldTotalCapital.setText(totalCapitalString);

            String totalInterestRateString = String.valueOf(cf.format(totalInterrestRate));

            fieldTotalInterestRate.setText(totalInterestRateString);

      }
    });
    cp.add(bBerechnung);
    labelTotalCaptital.setBounds(300, 85, 195, 20);
    labelTotalCaptital.setText("Kapital inkl. Zinsen über X Monate");
    labelTotalCaptital.setHorizontalAlignment(SwingConstants.CENTER);
    cp.add(labelTotalCaptital);
    fieldTotalCapital.setBounds(500, 85, 150, 20);
    fieldTotalCapital.setHorizontalAlignment(SwingConstants.CENTER);
    fieldTotalCapital.setEditable(false);
    cp.add(fieldTotalCapital);
    labelTotalInterestRate.setBounds(300, 150, 178, 20);
    labelTotalInterestRate.setText("Zinsen über X Monate Laufzeit ");
    labelTotalInterestRate.setHorizontalAlignment(SwingConstants.CENTER);
    cp.add(labelTotalInterestRate);
    fieldTotalInterestRate.setBounds(500, 150, 150, 20);
    fieldTotalInterestRate.setHorizontalAlignment(SwingConstants.CENTER);
    fieldTotalInterestRate.setEditable(false);
    cp.add(fieldTotalInterestRate);

    setVisible(true);
  }



  public static void main(String[] args) {
    new ZinsrechnerDPU();
  }

}