자바 맵 집합 2 급 연동 예제 실현
사고 분석:
1.전국(성,직할시,자치구)맵 집합,즉 링크 드 HashMap 대상 을 만 들 고 맵 인터페이스의 put()방법 으로 집합 에 지정 한 성과 도시 의 맵 관 계 를 추가 합 니 다.그 중에서 값 은 String 형 1 차원 배열 입 니 다.
코드 는 다음 과 같 습 니 다:
CityMap.java
import java.util.LinkedHashMap;
import java.util.Map;
public class CityMap {
/**
* （ ， ， ）
*/
public static Map<String,String[]> model=new LinkedHashMap<String, String[]>();
static{
model.put(" ", new String[]{" "});
model.put(" ", new String[]{" "});
model.put(" ", new String[]{" "});
model.put(" ", new String[]{" "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "});
model.put(" ", new String[]{" "," "," "," "," "," "," "," "," "," "," "," "," "});
}
}
3.JComboBox 류 의 setModel()방법 을 사용 하여 성 드 롭 다운 목록 에 성 정 보 를 추가 합 니 다.매개 변 수 는 이전 단계 에서 성 을 얻 는 방법 입 니 다.
4.성에 서 시/현 을 얻 는 방법 에 따라 Map 집합 을 만 들 고 절차 1 에서 얻 은 맵 집합 을 할당 하 며 Map 집합 get()방법 으로 지정 한 키 의 값 을 얻 습 니 다.즉,시/현 집합 으로 String[]형 1 차원 배열 을 만 들 고 시/현 집합 을 이 배열 에 할당 합 니 다.
5.성 드 롭 다운 목록 의 옵션 상태 변경 이 벤트 를 정의 합 니 다.이 이벤트 에서 JComboBox 류 의 getSelected Item()방법 으로 선 택 된 성 을 가 져 옵 니 다.기본 값 은 성 집합 에서 첫 번 째 값 입 니 다.그리고 JComboBox 류 의 removeAllItems()방법 으로 시/현 열 표를 비우 고 선 택 된 성에 따라 시/현 배열 을 가 져 옵 니 다.마지막 으로 JComboBox 의 setModel()방법 으로 시/현 목록 의 값 을 다시 추가 합 니 다.
코드 는 다음 과 같 습 니 다:
BackgroundPanel.java
import java.awt.Graphics;
import java.awt.Image;
import javax.swing.JPanel;
/**
*
*
* @author ZhongWei Lee
*/
public class BackgroundPanel extends JPanel {
/**
*
*/
private static final long serialVersionUID = 7758689434195492602L;
/**
*
*/
private Image image;
/**
*
*/
public BackgroundPanel() {
super();
setOpaque(false);
setLayout(null);
}
/**
*
*/
public void setImage(Image image) {
this.image = image;
}
@Override
protected void paintComponent(Graphics g) {//
if (image != null) {
int width = getWidth();//
int height = getHeight();
g.drawImage(image, 0, 0, width, height, this);//
}
super.paintComponent(g);//
}
}
import java.awt.Image;
import java.awt.Toolkit;
import java.io.BufferedInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;
import java.util.Iterator;
import javax.swing.ImageIcon;
/**
* Utility class for managing resources such as colors, fonts, images, etc.
*
* This class may be freely distributed as part of any application or plugin.
* <p>
* Copyright (c) 2003 - 2004, Instantiations, Inc. <br>All Rights Reserved
*
* @author scheglov_ke
*/
public class SwingResourceManager {
/**
* Maps image names to images
*/
private static HashMap<String, Image> m_ClassImageMap = new HashMap<String, Image>();
/**
* Returns an image encoded by the specified input stream
* @param is InputStream The input stream encoding the image data
* @return Image The image encoded by the specified input stream
*/
private static Image getImage(InputStream is) {
try {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
byte buf[] = new byte[1024 * 4];
while (true) {
int n = is.read(buf);
if (n == -1)
break;
baos.write(buf, 0, n);
}
baos.close();
return Toolkit.getDefaultToolkit().createImage(baos.toByteArray());
} catch (Throwable e) {
return null;
}
}
/**
* Returns an image stored in the file at the specified path relative to the specified class
* @param clazz Class The class relative to which to find the image
* @param path String The path to the image file
* @return Image The image stored in the file at the specified path
*/
public static Image getImage(Class<?> clazz, String path) {
String key = clazz.getName() + '|' + path;
Image image = m_ClassImageMap.get(key);
if (image == null) {
if ((path.length() > 0) && (path.charAt(0) == '/')) {
String newPath = path.substring(1, path.length());
image = getImage(new BufferedInputStream(clazz.getClassLoader().getResourceAsStream(newPath)));
} else {
image = getImage(clazz.getResourceAsStream(path));
}
m_ClassImageMap.put(key, image);
}
return image;
}
/**
* Returns an image stored in the file at the specified path
* @param path String The path to the image file
* @return Image The image stored in the file at the specified path
*/
public static Image getImage(String path) {
return getImage("default", path); //$NON-NLS-1$
}
/**
* Returns an image stored in the file at the specified path
* @param section String The storage section in the cache
* @param path String The path to the image file
* @return Image The image stored in the file at the specified path
*/
public static Image getImage(String section, String path) {
String key = section + '|' + SwingResourceManager.class.getName() + '|' + path;
Image image = m_ClassImageMap.get(key);
if (image == null) {
try {
FileInputStream fis = new FileInputStream(path);
image = getImage(fis);
m_ClassImageMap.put(key, image);
fis.close();
} catch (IOException e) {
return null;
}
}
return image;
}
/**
* Clear cached images in specified section
* @param section the section do clear
*/
public static void clearImages(String section) {
for (Iterator<String> I = m_ClassImageMap.keySet().iterator(); I.hasNext();) {
String key = I.next();
if (!key.startsWith(section + '|'))
continue;
Image image = m_ClassImageMap.get(key);
image.flush();
I.remove();
}
}
/**
* Returns an icon stored in the file at the specified path relative to the specified class
* @param clazz Class The class relative to which to find the icon
* @param path String The path to the icon file
* @return Icon The icon stored in the file at the specified path
*/
public static ImageIcon getIcon(Class<?> clazz, String path) {
return getIcon(getImage(clazz, path));
}
/**
* Returns an icon stored in the file at the specified path
* @param path String The path to the icon file
* @return Icon The icon stored in the file at the specified path
*/
public static ImageIcon getIcon(String path) {
return getIcon("default", path); //$NON-NLS-1$
}
/**
* Returns an icon stored in the file at the specified path
* @param section String The storage section in the cache
* @param path String The path to the icon file
* @return Icon The icon stored in the file at the specified path
*/
public static ImageIcon getIcon(String section, String path) {
return getIcon(getImage(section, path));
}
/**
* Returns an icon based on the specified image
* @param image Image The original image
* @return Icon The icon based on the image
*/
public static ImageIcon getIcon(Image image) {
if (image == null)
return null;
return new ImageIcon(image);
}
}
import java.awt.EventQueue;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import java.util.Map;
import java.util.Set;
import javax.swing.DefaultComboBoxModel;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.SwingConstants;
import javax.swing.UIManager;
import javax.swing.border.TitledBorder;
public class MainFrame extends JFrame {
/**
*
*/
private static final long serialVersionUID = -4595347311922711984L;
private JTextField textField_3;
private JTextField textField_1;
private JComboBox comboBox_1;
private JTextField textField;
private JComboBox cityComboBox;
private JComboBox comboBox;
/**
* Launch the application
*
* @param args
*/
public static void main(String args[]) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
UIManager.setLookAndFeel("com.sun.java.swing.plaf.nimbus.NimbusLookAndFeel");
MainFrame frame = new MainFrame();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the frame
*/
public MainFrame() {
getContentPane().setLayout(null);
setBounds(100, 100, 518, 379);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
// /
String province=(String)getProvince()[0];
setTitle(" / ");
final BackgroundPanel backgroundPanel = new BackgroundPanel();
backgroundPanel.setImage(SwingResourceManager.getImage(MainFrame.class, "/images/background.jpg"));
backgroundPanel.setBounds(0, 0, 510, 380);
getContentPane().add(backgroundPanel);
final JPanel panel = new JPanel();
panel.setOpaque(false);
panel.setBounds(36, 126, 438, 70);
backgroundPanel.add(panel);
panel.setLayout(null);
panel.setBorder(new TitledBorder(null, " ", TitledBorder.DEFAULT_JUSTIFICATION, TitledBorder.DEFAULT_POSITION, null, null));
cityComboBox = new JComboBox();
cityComboBox.setBounds(245, 25, 124, 27);
panel.add(cityComboBox);
cityComboBox.setModel(new DefaultComboBoxModel(getCity(province)));
comboBox = new JComboBox();
comboBox.setBounds(25, 25, 124, 27);
panel.add(comboBox);
comboBox.addItemListener(new ItemListener() {
public void itemStateChanged(final ItemEvent e) { //
itemChange();
}
});
comboBox.setModel(new DefaultComboBoxModel(getProvince())); //
final JLabel label = new JLabel();
label.setText(" / ");
label.setBounds(155, 30, 66, 18);
panel.add(label);
final JLabel label_1 = new JLabel();
label_1.setText(" / ");
label_1.setBounds(375, 30, 37, 18);
panel.add(label_1);
final JLabel label_2 = new JLabel();
label_2.setBounds(36, 43, 65, 18);
backgroundPanel.add(label_2);
label_2.setHorizontalAlignment(SwingConstants.RIGHT);
label_2.setHorizontalTextPosition(SwingConstants.LEADING);
label_2.setText(" ：");
textField = new JTextField();
textField.setBounds(113, 38, 154, 28);
backgroundPanel.add(textField);
final JLabel label_3 = new JLabel();
label_3.setBounds(36, 84, 65, 18);
backgroundPanel.add(label_3);
label_3.setHorizontalAlignment(SwingConstants.RIGHT);
label_3.setHorizontalTextPosition(SwingConstants.LEADING);
label_3.setText(" ：");
comboBox_1 = new JComboBox();
comboBox_1.setBounds(113, 81, 66, 25);
backgroundPanel.add(comboBox_1);
comboBox_1.setModel(new DefaultComboBoxModel(new String[] {" ", " "}));
final JLabel label_4 = new JLabel();
label_4.setBounds(36, 212, 65, 18);
backgroundPanel.add(label_4);
label_4.setHorizontalAlignment(SwingConstants.RIGHT);
label_4.setHorizontalTextPosition(SwingConstants.LEADING);
label_4.setText(" ：");
textField_1 = new JTextField();
textField_1.setBounds(113, 208, 367, 28);
backgroundPanel.add(textField_1);
final JLabel label_4_1 = new JLabel();
label_4_1.setBounds(36, 252, 65, 18);
backgroundPanel.add(label_4_1);
label_4_1.setHorizontalTextPosition(SwingConstants.LEADING);
label_4_1.setHorizontalAlignment(SwingConstants.RIGHT);
label_4_1.setText("E-mail：");
textField_3 = new JTextField();
textField_3.setBounds(113, 248, 367, 27);
backgroundPanel.add(textField_3);
final JButton button = new JButton();
button.setBounds(159, 289, 75, 28);
backgroundPanel.add(button);
button.setText(" ");
final JButton button_1 = new JButton();
button_1.setBounds(265, 289, 75, 28);
backgroundPanel.add(button_1);
button_1.setText(" ");
//
}
/**
* 、 ，
*
* @return
*/
public Object[] getProvince() {
Map<String, String[]> map = CityMap.model;// Map
Set<String> set = map.keySet(); // Map ， Set
Object[] province = set.toArray(); //
return province; //
}
/**
* /
*
* @param selectProvince
* @return
*/
public String[] getCity(String selectProvince) {
Map<String, String[]> map = CityMap.model; // Map
String[] arrCity = map.get(selectProvince); //
return arrCity; // /
}
private void itemChange() {
String selectProvince = (String) comboBox.getSelectedItem();
cityComboBox.removeAllItems(); // /
String[] arrCity = getCity(selectProvince); // /
cityComboBox.setModel(new DefaultComboBoxModel(arrCity)); // /
}
}
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