java在J2ME中使用哈希表实现从电话簿中读取联系人

Question

我遇到了一个难题，我不得不对从电话PIM读取的数据进行排序。在这样做的过程中，我丢失了每个联系人字段引用到电话号码的另一个字段，因为我使用了两个单独的向量，如下所示
分拣前

 Nna - +445535533                       
Ex - +373773737                         
Ab - +234575757                         
After sorting.(Which shouldn't be)
 Ab - +445535533
 Ex - +373773737
 Nna  - +234575757

这会产生一种不希望出现的行为，因为排序会删除向量的索引到索引指针，而选定的名称（在多个列表框中）将获得错误的编号
或者，
我使用了一个哈希表，目的是使用名称作为键，使用数字作为值
但这种配对意味着将不允许使用重复的名称作为密钥。因此，我把电话号码改成了钥匙。 我不想听起来像一个哭哭啼啼的婴儿，所以我在这里停了一会儿，希望你们能理解代码

我的问题
1.是否有更好的方法/算法来实现这一点
2.如何实现getSelectedItems（），使其能够从哈希表中获取多选列表中选定索引的编号

import java.util.Enumeration;
import java.util.Vector;
import java.util.Hashtable;
import javax.microedition.lcdui.List;
import javax.microedition.pim.Contact;
import javax.microedition.pim.ContactList;
import javax.microedition.pim.PIM;
import javax.microedition.pim.PIMException;

/**
 *
 * @author nnanna
 */
public class LoadContacts implements Operation {

    private boolean available;
    private Vector telNames = new Vector();
    Vector telNumbers = new Vector();
    Hashtable Listcontact = new Hashtable();
    private String[] names;

    public Vector getTelNames() {
        return telNames;
    }

    public Hashtable getListcontact() {
        return Listcontact;
    }

    public void execute() {
        try {
// go through all the lists
            String[] allContactLists = PIM.getInstance().listPIMLists(PIM.CONTACT_LIST);

            if (allContactLists.length != 0) {
                for (int i = 0; i < allContactLists.length; i++) {
                    System.out.println(allContactLists[i]);
                    System.out.println(allContactLists.length);
                    loadNames(allContactLists[i]);
                    System.out.println("Execute()");
                }

            } else {
                available = false;
            }
        } catch (PIMException e) {
            available = false;

        } catch (SecurityException e) {
            available = false;

        }
    }

    private void loadNames(String name) throws PIMException, SecurityException {
        ContactList contactList = null;

        try {
            contactList = (ContactList) PIM.getInstance().openPIMList(PIM.CONTACT_LIST, PIM.READ_ONLY, name);
            // First check that the fields we are interested in are supported(MODULARIZE)
            if (contactList.isSupportedField(Contact.FORMATTED_NAME) && contactList.isSupportedField(Contact.TEL)) {
                Enumeration items = contactList.items();
                Hashtable temp = new Hashtable();
                while (items.hasMoreElements()) {
                    Contact contact = (Contact) items.nextElement();
                    int telCount = contact.countValues(Contact.TEL);
                    int nameCount = contact.countValues(Contact.FORMATTED_NAME);
                    if (telCount > 0 && nameCount > 0) {
                        String contactName = contact.getString(Contact.FORMATTED_NAME, 0);
                        // go through all the phone availableContacts

                        for (int i = 0; i < telCount; i++) {
                            System.out.println("Read Telno");
                            int telAttributes = contact.getAttributes(Contact.TEL, i);
                            String telNumber = contact.getString(Contact.TEL, i);
                            Listcontact.put(telNumber, contactName);
                            temp.put(contactName, telNumber);
                        }
                        names = getSortedList();
//                            Listcontact = temp;
                        System.out.println(temp + "-------");
                        System.out.println(Listcontact + "*******");
                        shortenName(contactName, 20);
                    }
                    available = true;
                }
            } else {
                available = false;
            }
        } finally {
// always close it
            if (contactList != null) {
                contactList.close();
            }
        }
    }

    private void shortenName(String name, int length) {
        if (name.length() > length) {
            name = name.substring(0, 17) + "...";
        }
    }

    public Vector getSelectedItems(List lbx) {
        boolean[] arrSel = new boolean[lbx.size()];
        Vector selectedNumbers = new Vector();
        int selected = lbx.getSelectedFlags(arrSel);
        String selectedString;
        String result = "";
        for (int i = 0; i < arrSel.length; i++) {
            if (arrSel[i]) {
                selectedString = lbx.getString(lbx.getSelectedFlags(arrSel));
                result = result + " " + i;
                System.out.println(Listcontact.get(selectedString));
//                System.out.println(telNumbers.elementAt(i));
            }
        }
        return selectedNumbers;
    }

    private String[] sortResults(String data[]) {
        RecordSorter sorter = new RecordSorter();
        boolean changed = true;
        while (changed) {
            changed = false;
            for (int j = 0; j < (data.length - 1); j++) {
                String a = data[j], b = data[j + 1];
                if (a != null && b != null) {
                    int order = sorter.compare(a.getBytes(), b.getBytes());
                    if (order == RecordSorter.FOLLOWS) {
                        changed = true;
                        data[j] = b;
                        data[j + 1] = a;
                    }
                }
            }
        }
        return data;
    }

    public String[] getNames() {
        return names;
    }
        Vector elements = new Vector();
    private String[] getValueArray(Hashtable value) {

        System.out.println(Listcontact + " c");
        Enumeration e = value.elements();
        while (e.hasMoreElements()) {
            elements.addElement(e.nextElement());
        }
        String[] elementsArray = new String[elements.size()];
        elements.copyInto(elementsArray);
        elements.removeAllElements();
        System.out.println(elementsArray + " k");
        return elementsArray;
    }

    public void getDuplicates(Vector realValue) {
        Vector duplicate = new Vector();
        Enumeration e = realValue.elements();
        for (int i = 0; e.hasMoreElements(); i++) {
            if (duplicate.isEmpty() || !duplicate.elementAt(i).equals(e.nextElement())) {
                break;
            } else {
                duplicate.addElement(e.nextElement());
            }
        }
    }

    public String[] getSortedList() {
        return sortResults(getValueArray(Listcontact));
    }
}

Answer 1

在recordStore中插入联系人姓名和号码怎么样，这样以后就可以通过创建一个实现RecordComparator的类进行排序了

Answer 2

代码中的这句话毫无意义：

selectedString = lbx.getString(lbx.getSelectedFlags(arrSel))

上面的Perlcdui List API documentation将返回位于索引处的字符串，该字符串等于所选元素的数量为什么需要它

---

如果需要出于调试目的输出所选文本，请使用lbx.getString(i)

要实现getSelectedItems（），它可以获取多选列表中所选索引的编号，请执行以下操作：

    public Vector getSelectedItems(List lbx) {
        boolean[] arrSel = new boolean[lbx.size()];
        Vector selectedNumbers = new Vector();
        int selected = lbx.getSelectedFlags(arrSel);
        System.out.println("selected: [" + selected + "] elements in list");
        String selectedString;
        String result = "";
        for (int i = 0; i < arrSel.length; i++) {
            if (arrSel[i]) {
                // here, i is the selected index
                selectedNumbers.addElement(new Integer(i)); // add i to result
                String selectedString = lbx.getString(i);
                System.out.println("selected [" + selectedString
                        + "] text at index: [" + i + "]");
            }
        }
        return selectedNumbers;
    }

---

至于排序需求，只需删除HashTable并使用Vector正确设计的对象，而不是another answer中建议的——使用您自己的排序算法或某个第三方J2ME库中的排序算法

Answer 3

我建议你用Contact类来命名和数字向量。并对联系人数组进行排序，而不是对姓名数组进行排序