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Thread: Exception in thread "main" java.lang.NullPointerException

  1. April 24th, 2011, 10:04 PM #1
    isun
    isun is offline
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    Default Exception in thread "main" java.lang.NullPointerException

    i have this error :
    Exception in thread "main" java.lang.NullPointerException
    at aplikasiBarang.aplikasiBarang.tabelKosong(aplikasi Barang.java:531)
    at aplikasiBarang.aplikasiBarang.prosesCari(aplikasiB arang.java:507)
    at aplikasiBarang.aplikasiBarang.tampilTabel(aplikasi Barang.java:539)
    at aplikasiBarang.aplikasiBarang.<init>(aplikasiBaran g.java:278)
    at aplikasiBarang.aplikasiBarang.main(aplikasiBarang. java:629)

    and here is my code:

    package aplikasiBarang;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.*;
import javax.swing.text.*;
import java.awt.*;
import java.awt.event.*;
import java.sql.*;
import javax.swing.table.*;
import java.util.*;
import java.io.*;
/**
 *
 * @author deLL
 */
public class aplikasiBarang extends JFrame implements ActionListener{
    //deklarasi variabel
JLabel ljudul=new JLabel("::Data Barang::");
JLabel lkode=new JLabel("Kode Barang");
JLabel lnama=new JLabel("Nama Barang");
JLabel ltgl=new JLabel("Tanggal Beli");
JLabel lspek=new JLabel("Spesifikasi");
JLabel lharga=new JLabel("Harga Barang");
JLabel lstok=new JLabel("Stok Barang");
JLabel ltabel=new JLabel("::Daftar Data Barang");
JTextField tkode=new JTextField();
JTextField txtkode=new JTextField();
JTextField tnama=new JTextField();
JTextField tharga=new JTextField();
JTextField tstok=new JTextField();
JTextField tcari=new JTextField();
JComboBox ttglh=new JComboBox();
JComboBox ttglb=new JComboBox();
JComboBox ttglt=new JComboBox();
JComboBox tkolomcari=new JComboBox();
JButton btambah=new JButton("tambah");
JButton bsimpan=new JButton("simpan");
JButton bbatal=new JButton("batal");
JButton bubah=new JButton("ubah");
JButton bhapus=new JButton("hapus");
JButton bcari=new JButton("cari");
JButton btutup=new JButton("tutup");
JButton bnext=new JButton(">>");
JButton bprev=new JButton("<<");
JTextArea tspek=new JTextArea();
JPanel ptombol=new JPanel();
JTable tblbarang=new JTable();
JScrollPane scroll=new JScrollPane();
DefaultTableModel tabMode;
boolean simpan=false;
int n;
 
public aplikasiBarang(){
    ljudul.setBounds(new Rectangle(150,5,200,20));
    lkode.setBounds(new Rectangle(70,40,80,20));
    lnama.setBounds(new Rectangle(70,65,80,20));
    ltgl.setBounds(new Rectangle(70,90,90,20));
    lspek.setBounds(new Rectangle(70,115,80,20));
    lharga.setBounds(new Rectangle(70,160,80,20));
    lstok.setBounds(new Rectangle(70,185,80,20));
    tkode.setBounds(new Rectangle(170,40,60,20));
    txtkode.setBounds(new Rectangle(170,40,80,20));
    tnama.setBounds(new Rectangle(170,65,190,20));
    ttglh.setBounds(new Rectangle(170,90,40,20));
    ttglb.setBounds(new Rectangle(215,90,85,20));
    ttglt.setBounds(new Rectangle(305,90,55,20));
    tspek.setBounds(new Rectangle(170,115,190,40));
    tharga.setBounds(new Rectangle(170,160,100,20));
    tstok.setBounds(new Rectangle(170,185,50,20));
    btambah.setBounds(new Rectangle(10,220,80,20));
    bsimpan.setBounds(new Rectangle(100,220,80,20));
    bbatal.setBounds(new Rectangle(190,220,70,20));
    bubah.setBounds(new Rectangle(270,220,70,20));
    bhapus.setBounds(new Rectangle(350,220,70,20));
    btambah.setBounds(new Rectangle(10,220,80,20));
    bsimpan.setBounds(new Rectangle(100,220,80,20));
    bbatal.setBounds(new Rectangle(190,220,70,20));
    bubah.setBounds(new Rectangle(270,220,70,20));
    bhapus.setBounds(new Rectangle(350,220,70,20));
    btambah.setBounds(new Rectangle(10,220,80,20));
    bsimpan.setBounds(new Rectangle(100,220,80,20));
    bbatal.setBounds(new Rectangle(190,220,70,20));
    bubah.setBounds(new Rectangle(270,220,70,20));
    bhapus.setBounds(new Rectangle(350,220,70,20));
    btambah.setBounds(new Rectangle(10,220,80,20));
    bsimpan.setBounds(new Rectangle(100,220,80,20));
    bbatal.setBounds(new Rectangle(190,220,70,20));
    bubah.setBounds(new Rectangle(270,220,70,20));
    bhapus.setBounds(new Rectangle(350,220,70,20));
    tkolomcari.setBounds(new Rectangle(10,430,100,20));
    tcari.setBounds(new Rectangle(115,430,100,20));
    bcari.setBounds(new Rectangle(220,430,70,20));
    bprev.setBounds(new Rectangle(315,430,50,20));
    bnext.setBounds(new Rectangle(370,430,50,20));
    ltabel.setBounds(new Rectangle(10,225,150,20));
    scroll.setBounds(new Rectangle(10,275,410,150));
    btutup.setBounds(new Rectangle(350,460,70,20));
    //mengatur atribut komponen teks input
    ljudul.setFont(new Font("Impact",1,18));
    ljudul.setForeground(Color.magenta);
 
    //memberi nilai pada setiap komponen pilihan,komponen tanggal dan tkolomcari
    ttglh.addItem("");
        for (int i=1;i<=31;i++){
            String t=Integer.toString(i);
            if(i<10){
                t="0"+t;
            }
            ttglh.addItem(t);
        }
        ttglb.addItem("");
        ttglb.addItem("Januari");
        ttglb.addItem("Februari");
        ttglb.addItem("Maret");
        ttglb.addItem("April");
        ttglb.addItem("Mei");
        ttglb.addItem("Juni");
        ttglb.addItem("Juli");
        ttglb.addItem("Agustus");
        ttglb.addItem("September");
        ttglb.addItem("Oktober");
        ttglb.addItem("November");
        ttglb.addItem("Desember");
 
        ttglt.addItem("");
        for (int i=2005;i<(Calendar.getInstance().get(Calendar.YEAR));i++){
            ttglt.addItem(Integer.toString(i));
        }
        tkolomcari.addItem("::Pilih Kolom::");
        tkolomcari.addItem("Semua");
        tkolomcari.addItem("kode");
        tkolomcari.addItem("nama");
        tkolomcari.addItem("tgl_beli");
        tkolomcari.addItem("spesifikasi");
        tkolomcari.addItem("harga");
        tkolomcari.addItem("stok");
        //making table
        Object[]row={"no","kode","nama","tanggal beli","spesifikasi","harga","stok"};
        tkolomcari.addItemListener(new ItemListener() {
        public void itemStateChanged(ItemEvent ie){
            pilihKolomCari();
        }
        });
        //adding KeyListener in txt component
        tkode.addKeyListener(new KeyAdapter(){
            public void keyReleased(KeyEvent ke){
                if(ke.getKeyCode()==ke.VK_ENTER){
                    if(tkode.getText().equals("")){
 
                    }else{
                        tnama.requestFocus();
                    }
                }
            }
        });
        tnama.addKeyListener(new KeyAdapter(){
            public void keyReleased(KeyEvent ke){
                if(ke.getKeyCode()==ke.VK_ENTER){
                    if(tnama.getText().equals("")){
 
                    }else{
                        ttglh.requestFocus();
                    }
                }
            }
        });
    ttglh.addKeyListener(new KeyAdapter(){
        public void keyReleased(KeyEvent ke){
            if(ke.getKeyCode()==ke.VK_ENTER){
                if(ttglh.getSelectedItem().equals("")){
 
                }else{
                    ttglb.requestFocus();
                }
            }
        }
    });
    ttglb.addKeyListener(new KeyAdapter(){
        public void keyReleased(KeyEvent ke){
            if(ke.getKeyCode()==ke.VK_ENTER){
                if(ttglb.getSelectedItem().equals("")){
 
                }else{
                    ttglt.requestFocus();
                }
            }
        }
    });
    ttglt.addKeyListener(new KeyAdapter(){
        public void keyReleased(KeyEvent ke){
            if(ke.getKeyCode()==ke.VK_ENTER){
                if(ttglt.getSelectedItem().equals("")){
 
                }else{
                    tspek.requestFocus();
                }
            }
        }
    });
    tharga.addKeyListener(new KeyAdapter(){
        public void keyReleased(KeyEvent ke){
            if(ke.getKeyCode()==ke.VK_ENTER){
                if(tharga.getText().equals("")){
 
                }else{
                    tstok.requestFocus();
                }
            }
        }
    });
    tstok.addKeyListener(new KeyAdapter(){
        public void keyReleased(KeyEvent ke){
            if(ke.getKeyCode()==ke.VK_ENTER){
                if(tstok.getText().equals("")){
 
                }else{
                    bsimpan.requestFocus();
                }
            }
        }
    });
    //adding action listener to every button component;
    btambah.addActionListener(this);
    bsimpan.addActionListener(this);
    bbatal.addActionListener(this);
    bubah.addActionListener(this);
    bhapus.addActionListener(this);
    bcari.addActionListener(this);
    bnext.addActionListener(this);
    bprev.addActionListener(this);
    btutup.addActionListener(this);
    //adding every designed component into container Frame
    this.getContentPane().setLayout(null);
    getContentPane().add(ljudul);
    getContentPane().add(lkode);
    getContentPane().add(tkode);
    getContentPane().add(txtkode);
    getContentPane().add(lnama);
    getContentPane().add(tnama);
    getContentPane().add(ltgl);
    getContentPane().add(ttglh);
    getContentPane().add(ttglb);
    getContentPane().add(ttglt);
    getContentPane().add(lspek);
    getContentPane().add(tspek);
    getContentPane().add(lharga);
    getContentPane().add(tharga);
    getContentPane().add(lstok);
    getContentPane().add(tstok);
    getContentPane().add(btambah);
    getContentPane().add(bsimpan);
    getContentPane().add(bbatal);
    getContentPane().add(bubah);
    getContentPane().add(bhapus);
    getContentPane().add(tkolomcari);
    getContentPane().add(tcari);
    getContentPane().add(bnext);
    getContentPane().add(bprev);
    getContentPane().add(ltabel);
    getContentPane().add(scroll);
    getContentPane().add(btutup);
    //giving initialitation value to aplication
    txtkode.setEnabled(false);
    tblbarang.setEnabled(false);
    tcari.setEnabled(false);
    bcari.setEnabled(false);
    bprev.setEnabled(false);
    bnext.setEnabled(false);
    teksFalse();
    tombolFalse();
    koneksiDb koneksi=new koneksiDb();
    koneksi.panggilDriver();
    tampilTabel();
}
 
public void actionPerformed(ActionEvent tombol){
    if(tombol.getSource()==btambah){
            teksTrue();
            simpan=true;
            tkode.setVisible(true);
            txtkode.setVisible(true);
            bsimpan.setEnabled(true);
            bbatal.setEnabled(true);
            btambah.setEnabled(true);
            tkolomcari.setEnabled(true);
            btutup.setEnabled(true);
            tkode.requestFocus();
        }
        if(tombol.getSource()==bsimpan){
            if(simpan==true){
                if(tkode.getText().equals("")||tnama.getText().equals("")||ttglt.getSelectedItem().equals("")){
                    JOptionPane.showMessageDialog(null, "Isi semua data"+"nkode, nama dan tanggal"+"nwajib diisi");
                }else{
                    prosesSimpan();
                    tombolFalse();
                    teksFalse();
                    teksKosong();
                    btambah.setEnabled(true);
                    tkolomcari.setEnabled(true);
                    btutup.setEnabled(true);
                }
            }else{
                tombolUbah();
                tampilTabel();
                teksKosong();
                tombolFalse();
                teksFalse();
                btambah.setEnabled(true);
                tkolomcari.setEnabled(true);
                btutup.setEnabled(true);
            }
        }
        if(tombol.getSource()==bbatal){
            tombolFalse();
            teksKosong();
            teksFalse();
            btambah.setEnabled(true);
            tkolomcari.setEnabled(true);
            btutup.setEnabled(true);
        }
        if(tombol.getSource()==bcari){
            tombolCari();
            txtkode.setVisible(true);
            tkode.setVisible(true);
            tkolomcari.setSelectedItem("::Pilih Kolom::");
            tcari.setText("");
        }
        if(tombol.getSource()==bnext){
            tombolNext();
        }
        if(tombol.getSource()==bprev){
            tombolPrev();
        }
        if(tombol.getSource()==bubah){
            teksTrue();
            simpan=false;
            bubah.setEnabled(false);
            bhapus.setEnabled(false);
            btambah.setEnabled(false);
            tkolomcari.setEnabled(false);
            bprev.setEnabled(false);
            bnext.setEnabled(false);
            bsimpan.setEnabled(true);
        }
        if(tombol.getSource()==bhapus){
            prosesHapus();
            bprev.setEnabled(false);
            bnext.setEnabled(false);
            btambah.setEnabled(true);
            btutup.setEnabled(true);
            bubah.setEnabled(false);
            bhapus.setEnabled(false);
            bbatal.setEnabled(false);
 
        }
        if(tombol.getSource()==btutup){
            System.exit(0);
        }
    }
 
    void tombolFalse(){
        bsimpan.setEnabled(false);
        bbatal.setEnabled(false);
        bubah.setEnabled(false);
        bhapus.setEnabled(false);
        bnext.setEnabled(false);
        bprev.setEnabled(false);
    }
 
    void teksFalse(){
        tkode.setEnabled(false);
        tnama.setEnabled(false);
        ttglh.setEnabled(false);
        ttglb.setEnabled(false);
        ttglt.setEnabled(false);
        tharga.setEnabled(false);
        tspek.setEnabled(false);
        tstok.setEnabled(false);
    }
 
    void teksKosong(){
        tkode.setText("");
        txtkode.setText("");
        tnama.setText("");
        ttglh.setSelectedItem("");
        ttglb.setSelectedItem("");
        ttglt.setSelectedItem("");
        tharga.setText("");
        tspek.setText("");
        tstok.setText("");
    }
 
    void teksTrue(){
        tkode.setEnabled(true);
        tnama.setEnabled(true);
        ttglh.setEnabled(true);
        ttglb.setEnabled(true);
        ttglt.setEnabled(true);
        tharga.setEnabled(true);
        tspek.setEnabled(true);
        tstok.setEnabled(true);
    }
 
    void prosesSimpan(){
        try{
            Connection connect=new koneksiDb().condb();
            String sql="INSERT INTO tblbarang values(?,?,?,?,?,?)";
            PreparedStatement ps=connect.prepareStatement(sql);
            try{
                ps.setString(1, tkode.getText());
                simpanData(ps,0);
            }
            catch(SQLException sq){
 
            }
            tampilTabel();
            ps.close();
        }
        catch(Exception e){
            System.out.println("Pesan error:"+e);
        }
    }
 
    void simpanData(PreparedStatement ps, int u){
        try{
            ps.setString(2-u, tnama.getText());
            String hr=String.valueOf(ttglh.getSelectedItem());
            String bln=String.valueOf(ttglb.getSelectedItem());
            String thn=String.valueOf(ttglt.getSelectedItem());
            String tgl=hr+""+bln+""+thn;
            ps.setString(3-u, tgl);
            ps.setString(4-u, tspek.getText());
            ps.setString(5-u, tstok.getText());
            ps.executeUpdate();
        }
        catch(SQLException e){
            System.out.println("Gagal menyimpan SQL error:"+e);
            JOptionPane.showMessageDialog(null, "Gagal menyimpan kode kembar:"+"kode["+tkode.getText()+"] telah ada");
            tkode.setFocusable(true);
        }
    }
 
    void pilihKolomCari(){
        if(tkolomcari.getSelectedItem().equals("::Pilih Kolom::")){
            bcari.setEnabled(false);
            tcari.setEnabled(false);
        }else{
            //jika memilih semua
            if(tkolomcari.getSelectedItem().equals("Semua")){
                bcari.setEnabled(true);
                tcari.setEnabled(false);
            }else{
                bcari.setEnabled(true);
                tcari.setEnabled(true);
                tcari.requestFocus();
            }
        }
    }
 
    void tombolCari(){
        int r=tabMode.getRowCount();
        if(r==0){
            JOptionPane.showMessageDialog(null, "Database Kosong","Pesan",1);
        }else{
            if(tcari.isEnabled()==true){
                if(tcari.getText().equals("")){
                    JOptionPane.showMessageDialog(null, "Masukkan Parameter Pencarian","Pesan",1);
                }else{
                    String colom=tkolomcari.getSelectedItem().toString();
                    String param=tcari.getText();
                    String sql="SELECT * FROM tblbarang WHERE "+colom+"="+param+"";
                    prosesCari(sql);
                    int e=tabMode.getRowCount();
                    if(e<=0){
                        JOptionPane.showMessageDialog(null, "Data"+param+"Tidak ditemukan","Pesan",1);
                        tampilTabel();
                    }else{
                        aturTombolCari();
                        tampilTeks(0);
                    }
                }
            }else{
                tampilTabel();
                tampilTeks(0);
                aturTombolCari();
            }
        }
    }
 
    void aturTombolCari(){
        bubah.setEnabled(true);
        bhapus.setEnabled(true);
        bbatal.setEnabled(true);
        bcari.setEnabled(true);
        btambah.setEnabled(true);
        bprev.setEnabled(true);
        bnext.setEnabled(true);
        btutup.setEnabled(true);
    }
 
    void prosesCari(String sql){
        tabelKosong();
        int a=1;
        try{
            Connection connect=new koneksiDb().condb();
            Statement stat=connect.createStatement();
            ResultSet rset=stat.executeQuery(sql);
            while(rset.next()){
                String kode=rset.getString(1);
                String nama=rset.getString(2);
                String tgl=rset.getString(3);
                String spek=rset.getString(4);
                String harga=rset.getString(5);
                String stok=rset.getString(6);
                String no=Integer.toString(a);
                String[] data={no,kode,nama,tgl,spek,harga,stok};
                tabMode.addColumn(data);
                a++;
            }
            stat.close();
        }catch(SQLException e){
        }
    }
 
    public void tabelKosong(){
        int row=tabMode.getRowCount();
        for(int i=0;i<row;i++){
            tabMode.removeRow(0);
        }
    }
 
    void tampilTabel(){
        String sql="SELECT * FROM tblbarang";
        prosesCari(sql);
    }
 
    void tampilTeks(int row){
        String kode=tabMode.getValueAt(row, 1).toString();
        String nama=tabMode.getValueAt(row, 2).toString();
        String tgl=tabMode.getValueAt(row, 3).toString();
        int i=tgl.length();
        int x=i-4;
        Object tanggal=tgl.substring(0,2);
        Object bulan=tgl.substring(3,x-1);
        Object tahun=tgl.substring(x,i);
        String spek=tabMode.getValueAt(row, 4).toString();
        String harga=tabMode.getValueAt(row, 5).toString();
        String stok=tabMode.getValueAt(row, 6).toString();
        txtkode.setText(kode);
        tnama.setText(nama);
        ttglh.setSelectedItem(tanggal);
        ttglb.setSelectedItem(bulan);
        ttglt.setSelectedItem(tahun);
        tspek.setText(spek);
        tharga.setText(harga);
        tstok.setText(stok);
    }
 
    void tombolNext(){
        ++n;
        int c=tabMode.getRowCount();
        if(n>c-1){
            n=c-1;
            JOptionPane.showMessageDialog(null, "Record Terakhir");
        }
        tampilTeks(n);
 
    }
 
    void tombolPrev(){
        --n;
        if(n<0){
            n=0;
            JOptionPane.showMessageDialog(null, "Record pertama");
        }
        tampilTeks(n);
    }
 
    void tombolUbah(){
        String kode=txtkode.getText();
        String nama=tnama.getText();
        String message="Anda yakin ingin mengubah data"+"kode:"+kode+"nama"+nama;
        int pesan=JOptionPane.showConfirmDialog(null, message,"Ubah Data",JOptionPane.YES_NO_OPTION);
        if(pesan==0){
            try{
                Connection connect=new koneksiDb().condb();
                String param=tkode.getText();
                String sql="UPDATE tblbarang SET nama=?,tgl_beli=?,spek=?,harga=?,stok=? WHERE kode="+param+"";
                PreparedStatement ps=connect.prepareStatement(sql);
                simpanData(ps,1);
            }catch(SQLException e){
                System.out.println(e);
            }
        }
    }
 
    void prosesHapus(){
        String kode=txtkode.getText();
        String nama=tnama.getText();
        String spek=tspek.getText();
        String harga=tharga.getText();
        try{
            String message="Apakah Anda Yakin Menghapus Data"+"kode: "+kode+ "nama: "+nama+"spek: "+spek+"harga: "+harga;
            int pesan=JOptionPane.showConfirmDialog(null, message,"Konfirmasi Hapus Data",JOptionPane.YES_NO_OPTION);
            if(pesan==0){
                Connection connect=new koneksiDb().condb();
                String sql="DELETE FROM tblbarang WHERE kode="+kode+"";
                PreparedStatement pstat=connect.prepareStatement(sql);
                pstat.executeUpdate();
                tampilTabel();
                teksKosong();
            }
        }catch(SQLException se){
            String message="Gagal Menghapus Data"+"kode : "+kode+"nama : "+nama+"Error : "+se;
            JOptionPane.showMessageDialog(null, message);
        }
    }
 
/**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
        aplikasiBarang tampilan=new aplikasiBarang();
        tampilan.setTitle("Program Aplikasi Adventori Barang");
        tampilan.setSize(440,530);
        Dimension layar=Toolkit.getDefaultToolkit().getScreenSize();
        int l=(layar.width-tampilan.getSize().width)/2;
        int t=(layar.height-tampilan.getSize().height)/2;
        tampilan.setLocation(l, t);
        tampilan.setResizable(false);
        tampilan.setVisible(true);
        tampilan.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }
 
}



    Can you help me?thanks before...
    Last edited by copeg; April 25th, 2011 at 08:47 AM.
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  3. April 25th, 2011, 08:48 AM #2
    copeg
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    Default Re: Exception in thread "main" java.lang.NullPointerException

    That is a huge amount of code to wade through. Break the problem down, make sure your variables have been initialized, and try created an SSCCE that demonstrates the problem without all the excess code unrelated to the problem.
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  4. April 26th, 2011, 01:22 AM #3
    goldest
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    Cool Re: Exception in thread "main" java.lang.NullPointerException

    Seems like you have only declared the "DefaultTableModel" but not initialized it and thats what is causing the NullPointerException.

    Initialize it properly,
    DefaultTableModel tabMode = new DefaultTableModel();
    Hope that helps,

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  5. April 26th, 2011, 10:29 PM #4
    isun
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    Default Re: Exception in thread "main" java.lang.NullPointerException

    thank you so much...i've added the initialitation, but now i've got new problem:

    gagal di com.mysql.jdbc.exceptions.jdbc4.CommunicationsExce ption: Communications link failure
    Exception in thread "main" java.lang.NullPointerException

    Last packet sent to the server was 0 ms ago.
    at aplikasiBarang.aplikasiBarang.prosesCari(aplikasiB arang.java:511)
    at aplikasiBarang.aplikasiBarang.tampilTabel(aplikasi Barang.java:539)
    at aplikasiBarang.aplikasiBarang.<init>(aplikasiBaran g.java:278)
    at aplikasiBarang.aplikasiBarang.main(aplikasiBarang. java:629)
    Java Result: 1

    this is my connection code:
    public class koneksiDb {
    koneksiDb(){
 
    }
    Connection con;
 
    public void panggilDriver(){
        try{
            String driver="com.mysql.jdbc.Driver";
            Class.forName(driver);
            System.out.println("Memanggil Driver sukses");
        }catch(ClassNotFoundException cnfe){
            System.out.println("Pesan error: "+cnfe);
        }
    }
 
    public Connection condb(){
        Connection koneksi=null;
        try{
            String url="jdbc:mysql://localhost:3307/minimarket";
            String user="root";
            String pass="";
            koneksi = DriverManager.getConnection(url,user,pass);
            System.out.println("Koneksi database suskses");
        }catch(SQLException e){
            System.out.println("gagal di "+e);
        }
        return koneksi;
    }
 
}
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  6. April 28th, 2011, 09:22 AM #5
    dlorde
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    Default Re: Exception in thread "main" java.lang.NullPointerException

    The error message is telling you that you tried to use a null reference in the prosesCari method at line 511 in the aplikasiBarang.java file. You'll have to locate that line and figure out what you're trying to use that could be null there.
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