请帮我搜索算法？ [关闭]

因此，我正在使用搜索算法编写程序。 这是我的代码，

public class BismillahKasir3 extends javax.swing.JFrame {

    LinkedList <String> namaa = new LinkedList<String>();
    LinkedList <String> noohp = new LinkedList<String>();
    LinkedList <String> kodebuku = new LinkedList<String>();
    LinkedList <String> judulbuku = new LinkedList<String>();
    static linked buku = new linked();
    static node chatta = new node();

    /**
     * Launch the application.
     */
        Scanner input = new Scanner(System.in);

        buku.tambahakhir("BUKU", "A001", 13000);
        buku.tambahakhir("5 cm", "A002", 2000);
        buku.tambahakhir("1000 Muslim Mengejar Bintang", "A003", 3000);
        buku.tambahakhir("bismillah", "A004", 5000);

        tfKODE = new JTextField();
        tfKODE.setFont(new Font("Tahoma", Font.PLAIN, 14));
        tfKODE.setBounds(99, 62, 197, 29);
        framekasir3.getContentPane().add(tfKODE);
        tfKODE.setColumns(10);

        linesearch uwu = new linesearch();
        JButton btnCari = new JButton("Cari");
        btnCari.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent arg0) {
                chatta = uwu.search(buku, tfKODE.getText());
                if(uwu.indeks ==-1) {
                    JOptionPane.showMessageDialog(null, "Judul buku dengan kode " +chatta.kode+ " tidak ditemukan");
                    tfNAMA.setText("");
                    tfSATUAN.setText("");
                }
                else {
                    tfNAMA.setText("" + chatta.judul);
                    tfSATUAN.setText("" +chatta.harga);
                }
            }
        });
        btnCari.setFont(new Font("Tahoma", Font.PLAIN, 14));
        btnCari.setBounds(99, 96, 89, 23);
        framekasir3.getContentPane().add(btnCari);

        tfNAMA = new JTextField();
        tfNAMA.setFont(new Font("Tahoma", Font.PLAIN, 10));
        tfNAMA.setEditable(false);
        tfNAMA.setBounds(99, 129, 197, 29);
        framekasir3.getContentPane().add(tfNAMA);
        tfNAMA.setColumns(10);

        tfSATUAN = new JTextField();
        tfSATUAN.setFont(new Font("Tahoma", Font.PLAIN, 14));
        tfSATUAN.setEditable(false);
        tfSATUAN.setBounds(99, 169, 197, 29);
        framekasir3.getContentPane().add(tfSATUAN);
        tfSATUAN.setColumns(10);

        }
}

class node {
    String kode;
    String judul;
    int harga;
    node next;
    node prev;
}

class linesearch{
    int indeks;
    public node search(linked b, String kodee){
        indeks = -1;
        node cari = new node();
        cari.kode = kodee;
        node ganti = b.head;
        for (int i = 0; i< b.ukuran(); i++) {
            String smbrng = ganti.kode;
            if(kodee.equals(smbrng)) {
                indeks = i;
                cari.judul = ganti.judul;
                cari.harga = ganti.harga;}
            ganti = ganti.next;
            }
        return cari;
            }
        }

class linked {
    node head;

    public int ukuran() {
        node em = head;
        int size = 0;
        while (em!= null) {
            size = size+1;
            em = em.next;}
        return size;
    }

    public node indeks(int a) {
        node ma = head;
        if (a<ukuran()&& a>= 0) {
            for (int i = 0; i<a; i++) {
                ma = ma.next;
            }
            return ma;}
        else return null;}

    public void tambahawal (String a, String b, int c) {
        node em = new node();
        em.judul = a;
        em.kode = b;
        em.harga = c;
        em.next = head;
        em.prev = null;
        if(head!=null)
            head.prev = em;
            head = em;
            }

    public void tambahakhir (String a, String b, int c) {
        node em = new node();
        em.judul = a;
        em.kode = b;
        em.harga = c;
        node ganti = head;
        if(kosong()) {
            tambahawal(a,b,c);
        }
        else {
            while(ganti.next!=null) {
                ganti = ganti.next;
                ganti.next = em;
                em.prev = ganti;
                em.next = null;
            }
        }
        }

        public void tampil() {
            node em = head;
            System.out.println("\n" +em.kode + "\t" + em.judul + "\t" + em.harga);
            em = em.next;
            while(em!= null) {
                System.out.println("\n" +em.kode+ "\t" + em.judul + "\t" + em.harga);
                em = em.next;
            }
    }

    }

事实是，当我搜索“ A001”时，结果很好。但是当我搜索“ A002”或“ A003”或“ A004”时，结果不存在（但没有给我一个错误）。

你能帮我吗？先感谢您...