Membuat Kalkulator Menggunakan Netbeans

Coba saja source code untuk membuatnya, saya membuatnya menggunakan Netbeans, lalu buatlah kelas JFrame Form pada Project Java Application. Kodingan harus di sesuaikan dengan nama kelas dan foldernya. Berikut screenshotnya:

 Berikut kodingannya:
======================================================================

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */

package GUI;

import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.swing.JOptionPane;

/**
 *
 * @author user
 */
public class KalkulatorFix extends javax.swing.JFrame {

    /** Creates new form KalkulatorFix */
    public KalkulatorFix() {
        initComponents();
    }

    /** This method is called from within the constructor to
     * initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is
     * always regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                         
    private void initComponents() {

        satu = new javax.swing.JButton();
        dua = new javax.swing.JButton();
        tiga = new javax.swing.JButton();
        enam = new javax.swing.JButton();
        lima = new javax.swing.JButton();
        empat = new javax.swing.JButton();
        sembilan = new javax.swing.JButton();
        delapan = new javax.swing.JButton();
        tujuh = new javax.swing.JButton();
        tampilanhasil = new javax.swing.JTextField();
        kali = new javax.swing.JButton();
        kurang = new javax.swing.JButton();
        bagi = new javax.swing.JButton();
        tambah = new javax.swing.JButton();
        c = new javax.swing.JButton();
        hasil = new javax.swing.JButton();
        jLabel1 = new javax.swing.JLabel();
        nol = new javax.swing.JButton();
        persen = new javax.swing.JButton();
        pangkat = new javax.swing.JButton();
        koma = new javax.swing.JButton();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        setBackground(new java.awt.Color(0, 153, 153));
        setCursor(new java.awt.Cursor(java.awt.Cursor.HAND_CURSOR));

        satu.setBackground(new java.awt.Color(102, 255, 204));
        satu.setFont(new java.awt.Font("OCR A Extended", 0, 12)); // NOI18N
        satu.setText("1");
        satu.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseReleased(java.awt.event.MouseEvent evt) {
                satuMouseReleased(evt);
            }
        });
        satu.addChangeListener(new javax.swing.event.ChangeListener() {
            public void stateChanged(javax.swing.event.ChangeEvent evt) {
                satuStateChanged(evt);
            }
        });
        satu.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                satuActionPerformed(evt);
            }
        });
        satu.addInputMethodListener(new java.awt.event.InputMethodListener() {
            public void caretPositionChanged(java.awt.event.InputMethodEvent evt) {
                satuCaretPositionChanged(evt);
            }
            public void inputMethodTextChanged(java.awt.event.InputMethodEvent evt) {
            }
        });

        dua.setBackground(new java.awt.Color(102, 255, 204));
        dua.setFont(new java.awt.Font("OCR A Extended", 0, 12)); // NOI18N
        dua.setText("2");
        dua.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseReleased(java.awt.event.MouseEvent evt) {
                duaMouseReleased(evt);
            }
        });
        dua.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                duaActionPerformed(evt);
            }
        });

        tiga.setBackground(new java.awt.Color(102, 255, 204));
        tiga.setFont(new java.awt.Font("OCR A Extended", 0, 12)); // NOI18N
        tiga.setText("3");
        tiga.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseReleased(java.awt.event.MouseEvent evt) {
                tigaMouseReleased(evt);
            }
        });

        enam.setBackground(new java.awt.Color(102, 255, 204));
        enam.setFont(new java.awt.Font("OCR A Extended", 0, 12)); // NOI18N
        enam.setText("6");
        enam.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseReleased(java.awt.event.MouseEvent evt) {
                enamMouseReleased(evt);
            }
        });

        lima.setBackground(new java.awt.Color(102, 255, 204));
        lima.setFont(new java.awt.Font("OCR A Extended", 0, 12)); // NOI18N
        lima.setText("5");
        lima.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseReleased(java.awt.event.MouseEvent evt) {
                limaMouseReleased(evt);
            }
        });

        empat.setBackground(new java.awt.Color(102, 255, 204));
        empat.setFont(new java.awt.Font("OCR A Extended", 0, 12)); // NOI18N
        empat.setText("4");
        empat.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseReleased(java.awt.event.MouseEvent evt) {
                empatMouseReleased(evt);
            }
        });

        sembilan.setBackground(new java.awt.Color(102, 255, 204));
        sembilan.setFont(new java.awt.Font("OCR A Extended", 0, 12)); // NOI18N
        sembilan.setText("9");
        sembilan.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseReleased(java.awt.event.MouseEvent evt) {
                sembilanMouseReleased(evt);
            }
        });

        delapan.setBackground(new java.awt.Color(102, 255, 204));
        delapan.setFont(new java.awt.Font("OCR A Extended", 0, 12)); // NOI18N
        delapan.setText("8");
        delapan.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseReleased(java.awt.event.MouseEvent evt) {
                delapanMouseReleased(evt);
            }
        });

        tujuh.setBackground(new java.awt.Color(102, 255, 204));
        tujuh.setFont(new java.awt.Font("OCR A Extended", 0, 12)); // NOI18N
        tujuh.setText("7");
        tujuh.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseReleased(java.awt.event.MouseEvent evt) {
                tujuhMouseReleased(evt);
            }
        });

        tampilanhasil.setFont(new java.awt.Font("NSimSun", 0, 12)); // NOI18N
        tampilanhasil.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                tampilanhasilActionPerformed(evt);
            }
        });

        kali.setBackground(new java.awt.Color(102, 255, 204));
        kali.setFont(new java.awt.Font("Tahoma", 1, 10)); // NOI18N
        kali.setForeground(new java.awt.Color(0, 102, 153));
        kali.setText("X");
        kali.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseReleased(java.awt.event.MouseEvent evt) {
                kaliMouseReleased(evt);
            }
        });

        kurang.setBackground(new java.awt.Color(102, 255, 204));
        kurang.setFont(new java.awt.Font("Tahoma", 1, 14)); // NOI18N
        kurang.setForeground(new java.awt.Color(0, 102, 153));
        kurang.setText("-");
        kurang.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseReleased(java.awt.event.MouseEvent evt) {
                kurangMouseReleased(evt);
            }
        });

        bagi.setBackground(new java.awt.Color(102, 255, 204));
        bagi.setFont(new java.awt.Font("Tahoma", 1, 12)); // NOI18N
        bagi.setForeground(new java.awt.Color(0, 102, 153));
        bagi.setText("/");
        bagi.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseReleased(java.awt.event.MouseEvent evt) {
                bagiMouseReleased(evt);
            }
        });

        tambah.setBackground(new java.awt.Color(102, 255, 204));
        tambah.setFont(new java.awt.Font("Tahoma", 1, 14)); // NOI18N
        tambah.setForeground(new java.awt.Color(0, 102, 153));
        tambah.setText("+");
        tambah.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseReleased(java.awt.event.MouseEvent evt) {
                tambahMouseReleased(evt);
            }
        });

        c.setBackground(new java.awt.Color(102, 255, 204));
        c.setFont(new java.awt.Font("Stencil", 1, 14)); // NOI18N
        c.setForeground(new java.awt.Color(255, 51, 51));
        c.setText("C");
        c.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseReleased(java.awt.event.MouseEvent evt) {
                cMouseReleased(evt);
            }
        });
        c.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                cActionPerformed(evt);
            }
        });

        hasil.setBackground(new java.awt.Color(102, 255, 204));
        hasil.setFont(new java.awt.Font("Showcard Gothic", 1, 14)); // NOI18N
        hasil.setText("=");
        hasil.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseReleased(java.awt.event.MouseEvent evt) {
                hasilMouseReleased(evt);
            }
        });
        hasil.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                hasilActionPerformed(evt);
            }
        });

        jLabel1.setFont(new java.awt.Font("Shonar Bangla", 0, 11)); // NOI18N
        jLabel1.setText("By Agus Salim");

        nol.setBackground(new java.awt.Color(102, 255, 204));
        nol.setFont(new java.awt.Font("OCR A Extended", 0, 12)); // NOI18N
        nol.setText("0");
        nol.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseReleased(java.awt.event.MouseEvent evt) {
                nolMouseReleased(evt);
            }
        });
        nol.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                nolActionPerformed(evt);
            }
        });

        persen.setBackground(new java.awt.Color(102, 255, 204));
        persen.setFont(new java.awt.Font("Tahoma", 1, 11)); // NOI18N
        persen.setForeground(new java.awt.Color(0, 102, 153));
        persen.setText("%");
        persen.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseReleased(java.awt.event.MouseEvent evt) {
                persenMouseReleased(evt);
            }
        });

        pangkat.setBackground(new java.awt.Color(102, 255, 204));
        pangkat.setFont(new java.awt.Font("Tahoma", 1, 11)); // NOI18N
        pangkat.setForeground(new java.awt.Color(0, 102, 153));
        pangkat.setText("mod");
        pangkat.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseReleased(java.awt.event.MouseEvent evt) {
                pangkatMouseReleased(evt);
            }
        });

        koma.setBackground(new java.awt.Color(102, 255, 204));
        koma.setFont(new java.awt.Font("Tahoma", 1, 11)); // NOI18N
        koma.setForeground(new java.awt.Color(0, 102, 153));
        koma.setText(".");
        koma.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseReleased(java.awt.event.MouseEvent evt) {
                komaMouseReleased(evt);
            }
        });

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addContainerGap()
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addComponent(empat, javax.swing.GroupLayout.Alignment.TRAILING, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                    .addComponent(persen, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                    .addComponent(tujuh, javax.swing.GroupLayout.Alignment.TRAILING, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                    .addComponent(pangkat, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                    .addComponent(satu, javax.swing.GroupLayout.Alignment.TRAILING, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addComponent(lima, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                    .addComponent(c, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                    .addComponent(nol, javax.swing.GroupLayout.Alignment.TRAILING, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                    .addComponent(delapan, javax.swing.GroupLayout.Alignment.TRAILING, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                    .addComponent(dua, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
                    .addComponent(hasil, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                    .addGroup(layout.createSequentialGroup()
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING, false)
                            .addComponent(koma, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                            .addComponent(sembilan, javax.swing.GroupLayout.DEFAULT_SIZE, 66, Short.MAX_VALUE))
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
                            .addComponent(kurang, javax.swing.GroupLayout.DEFAULT_SIZE, 55, Short.MAX_VALUE)
                            .addComponent(tambah, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)))
                    .addGroup(layout.createSequentialGroup()
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING, false)
                            .addComponent(tiga, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                            .addComponent(enam, javax.swing.GroupLayout.DEFAULT_SIZE, 66, Short.MAX_VALUE))
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                            .addGroup(layout.createSequentialGroup()
                                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                                .addComponent(bagi, javax.swing.GroupLayout.PREFERRED_SIZE, 55, javax.swing.GroupLayout.PREFERRED_SIZE))
                            .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                                .addGap(10, 10, 10)
                                .addComponent(kali, javax.swing.GroupLayout.PREFERRED_SIZE, 55, javax.swing.GroupLayout.PREFERRED_SIZE)))))
                .addGap(8, 8, 8))
            .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                .addComponent(tampilanhasil, javax.swing.GroupLayout.PREFERRED_SIZE, 273, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addContainerGap())
            .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                .addGap(0, 0, Short.MAX_VALUE)
                .addComponent(jLabel1))
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addContainerGap()
                .addComponent(tampilanhasil, javax.swing.GroupLayout.PREFERRED_SIZE, 56, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(satu, javax.swing.GroupLayout.PREFERRED_SIZE, 45, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(dua, javax.swing.GroupLayout.PREFERRED_SIZE, 45, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(tiga, javax.swing.GroupLayout.PREFERRED_SIZE, 45, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(kali, javax.swing.GroupLayout.PREFERRED_SIZE, 45, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(lima, javax.swing.GroupLayout.PREFERRED_SIZE, 45, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(empat, javax.swing.GroupLayout.PREFERRED_SIZE, 45, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(enam, javax.swing.GroupLayout.PREFERRED_SIZE, 45, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(bagi, javax.swing.GroupLayout.PREFERRED_SIZE, 45, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addComponent(delapan, javax.swing.GroupLayout.PREFERRED_SIZE, 45, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                        .addComponent(sembilan, javax.swing.GroupLayout.PREFERRED_SIZE, 45, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addComponent(kurang, javax.swing.GroupLayout.PREFERRED_SIZE, 45, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addComponent(tujuh, javax.swing.GroupLayout.PREFERRED_SIZE, 45, javax.swing.GroupLayout.PREFERRED_SIZE)))
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(nol, javax.swing.GroupLayout.PREFERRED_SIZE, 45, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(koma, javax.swing.GroupLayout.PREFERRED_SIZE, 45, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(persen, javax.swing.GroupLayout.PREFERRED_SIZE, 45, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(tambah, javax.swing.GroupLayout.PREFERRED_SIZE, 45, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(hasil, javax.swing.GroupLayout.PREFERRED_SIZE, 45, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(c, javax.swing.GroupLayout.PREFERRED_SIZE, 45, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(pangkat, javax.swing.GroupLayout.PREFERRED_SIZE, 44, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                .addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 14, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addGap(0, 0, 0))
        );

        pack();
    }// </editor-fold>                       

    private void satuCaretPositionChanged(java.awt.event.InputMethodEvent evt) {                                         
    // TODO add your handling code here:
    }                                        

    private void satuStateChanged(javax.swing.event.ChangeEvent evt) {                                 
        // TODO add your handling code here:
    }                                

    private void satuActionPerformed(java.awt.event.ActionEvent evt) {                                    

        // TODO add your handling code here:
    }                                   

    private void tampilanhasilActionPerformed(java.awt.event.ActionEvent evt) {                                             
       
        // TODO add your handling code here:
    }                                            

    private void satuMouseReleased(java.awt.event.MouseEvent evt) {                                  
        String nilai = tampilanhasil.getText()+1;
        tampilanhasil.setText(nilai);
        // TODO add your handling code here:
    }                                 

    private void nolActionPerformed(java.awt.event.ActionEvent evt) {                                   
       String nilai = tampilanhasil.getText();
        tampilanhasil.setText(nilai); // TODO add your handling code here:
    }                                  

    private void duaMouseReleased(java.awt.event.MouseEvent evt) {                                 
       String nilai = tampilanhasil.getText()+2;
        tampilanhasil.setText(nilai); // TODO add your handling code here:
    }                                

    private void tigaMouseReleased(java.awt.event.MouseEvent evt) {                                  
       String nilai = tampilanhasil.getText()+3;
        tampilanhasil.setText(nilai); // TODO add your handling code here:
    }                                 

    private void empatMouseReleased(java.awt.event.MouseEvent evt) {                                   
      String nilai = tampilanhasil.getText()+4;
        tampilanhasil.setText(nilai);  // TODO add your handling code here:
    }                                  

    private void limaMouseReleased(java.awt.event.MouseEvent evt) {                                  
       String nilai = tampilanhasil.getText()+5;
        tampilanhasil.setText(nilai); // TODO add your handling code here:
    }                                 

    private void enamMouseReleased(java.awt.event.MouseEvent evt) {                                  
       String nilai = tampilanhasil.getText()+6;
        tampilanhasil.setText(nilai); // TODO add your handling code here:
    }                                 

    private void tujuhMouseReleased(java.awt.event.MouseEvent evt) {                                   
        String nilai = tampilanhasil.getText()+7;
        tampilanhasil.setText(nilai);// TODO add your handling code here:
    }                                  

    private void delapanMouseReleased(java.awt.event.MouseEvent evt) {                                     
        String nilai = tampilanhasil.getText()+8;
        tampilanhasil.setText(nilai);// TODO add your handling code here:
    }                                    

    private void sembilanMouseReleased(java.awt.event.MouseEvent evt) {                                      
        String nilai = tampilanhasil.getText()+9;
        tampilanhasil.setText(nilai);// TODO add your handling code here:
    }                                     

    private void nolMouseReleased(java.awt.event.MouseEvent evt) {                                 
        String nilai = tampilanhasil.getText()+0;
        tampilanhasil.setText(nilai);// TODO add your handling code here:
    }                                

    private void cMouseReleased(java.awt.event.MouseEvent evt) {                               
        String nilai = tampilanhasil.getText();
        tampilanhasil.setText(null);// TODO add your handling code here:
    }                              

    private void kaliMouseReleased(java.awt.event.MouseEvent evt) {                                  
        String nilai = tampilanhasil.getText()+"*";
        tampilanhasil.setText(nilai);// TODO add your handling code here:
    }                                 

    private void bagiMouseReleased(java.awt.event.MouseEvent evt) {                                  
        String nilai = tampilanhasil.getText()+"/";
        tampilanhasil.setText(nilai);// TODO add your handling code here:
    }                                 

    private void kurangMouseReleased(java.awt.event.MouseEvent evt) {                                    
       String nilai = tampilanhasil.getText()+"-";
        tampilanhasil.setText(nilai); // TODO add your handling code here:
    }                                   

    private void tambahMouseReleased(java.awt.event.MouseEvent evt) {                                    
       String nilai = tampilanhasil.getText()+"+";
        tampilanhasil.setText(nilai); // TODO add your handling code here:
    }                                   

    private void hasilMouseReleased(java.awt.event.MouseEvent evt) {                                   
        ScriptEngineManager hs= new ScriptEngineManager();
        ScriptEngine hsl = hs.getEngineByName("JavaScript");
       
        try{tampilanhasil.setText(hsl.eval(tampilanhasil.getText()).toString());}
        catch (Exception e){JOptionPane.showMessageDialog(null,"Inputan Salah");}
// TODO add your handling code here:
    }                                  

    private void hasilActionPerformed(java.awt.event.ActionEvent evt) {                                     
        // TODO add your handling code here:
    }                                    

    private void persenMouseReleased(java.awt.event.MouseEvent evt) {                                    
       String nilai = tampilanhasil.getText()+"/100";
        tampilanhasil.setText(nilai); // TODO add your handling code here:
    }                                   

    private void pangkatMouseReleased(java.awt.event.MouseEvent evt) {                                     
        String nilai = tampilanhasil.getText()+'%';
        tampilanhasil.setText(nilai);        // TODO add your handling code here:
    }                                    

    private void komaMouseReleased(java.awt.event.MouseEvent evt) {                                  
        String nilai = tampilanhasil.getText()+".";
        tampilanhasil.setText(nilai);        // TODO add your handling code here:
    }                                 

    private void duaActionPerformed(java.awt.event.ActionEvent evt) {                                   
        // TODO add your handling code here:
    }                                  

    private void cActionPerformed(java.awt.event.ActionEvent evt) {                                 
        // TODO add your handling code here:
    }                                

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        /* Set the Nimbus look and feel */
        //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
        /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
         * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
         */
        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Nimbus".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(KalkulatorFix.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(KalkulatorFix.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(KalkulatorFix.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(KalkulatorFix.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        //</editor-fold>

        /* Create and display the form */
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new KalkulatorFix().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify                    
    private javax.swing.JButton bagi;
    private javax.swing.JButton c;
    private javax.swing.JButton delapan;
    private javax.swing.JButton dua;
    private javax.swing.JButton empat;
    private javax.swing.JButton enam;
    private javax.swing.JButton hasil;
    private javax.swing.JLabel jLabel1;
    private javax.swing.JButton kali;
    private javax.swing.JButton koma;
    private javax.swing.JButton kurang;
    private javax.swing.JButton lima;
    private javax.swing.JButton nol;
    private javax.swing.JButton pangkat;
    private javax.swing.JButton persen;
    private javax.swing.JButton satu;
    private javax.swing.JButton sembilan;
    private javax.swing.JButton tambah;
    private javax.swing.JTextField tampilanhasil;
    private javax.swing.JButton tiga;
    private javax.swing.JButton tujuh;
    // End of variables declaration                  

}

======================================================================

Oke sekian terima kasih, semoga bermanfaat :)