从下面的代码中，我可以向相关的JList添加主题和注释。我可以将代码存储在java空间中，并在必要时进行检索，但是，我想将数据永久存储在JList中，以便当新用户登录时可以看到输入的数据。
使用下面的代码，有人可以建议我该怎么做。
import net.jini.core.event.RemoteEvent;
import net.jini.core.event.RemoteEventListener;
import net.jini.core.event.UnknownEventException;
import net.jini.core.lease.Lease;
import net.jini.space.JavaSpace;
import net.jini.space.JavaSpace05;
import net.jini.space.MatchSet;
import javax.swing.*;
import java.awt.*;
import java.rmi.RemoteException;
import java.util.Collections;
public class MRHomePage extends JFrame implements RemoteEventListener{
private static final long TWO_SECONDS = 2 * 1000; // two thousand milliseconds
private static final long ONESECOND = 1000; // one thousand milliseconds
public static MRQueueTopicCreate users = new MRQueueTopicCreate();
public LoginPage login;
public String currentUser;
public DefaultListModel<MRQueueTopicCreate> topicListModel;
public DefaultListModel<MRQueueTopicCreate> allListModel;
public DefaultListModel<MRQueueTopicCreate> selectTopicsModel;
public DefaultListModel<MRQueueCommentCreate> commentListModel;
String User = users.TopicUserID;
private JavaSpace space;
private JTextField newComment, jobNumberOut, topicIn, usernameString;
private Label username;
private JList topicPostArea, topicStoreArea;
private DefaultComboBoxModel combo;
private JTextArea box, privateArea;
public static boolean hasRunMethod = false;
private JList list, allDetailsList, selectTopicsList, newList;
public MRHomePage() {
space = SpaceUtils.getSpace();
if (space == null) {
System.err.println("Failed to find the javaspace");
System.exit(1);
}
initComponents();
pack();
startUP();
//addTopic();
setVisible(true);
//getAllTopics();
}
public static void main(String[] args) {
new MRHomePage().setVisible(true);
}
public void initComponents() {
addWindowListener(new java.awt.event.WindowAdapter() {
public void windowClosing(java.awt.event.WindowEvent evt) {
System.exit(0);
}
});
//container
Container cp = getContentPane();
cp.setLayout(new BorderLayout());
//panels
JPanel jPanel1 = new JPanel();
jPanel1.setLayout(new FlowLayout(FlowLayout.LEFT));
JPanel jPanel2 = new JPanel();
jPanel2.setLayout(new FlowLayout());
JPanel jpanel3 = new JPanel();
jpanel3.setLayout(new FlowLayout());
//labels
JLabel commentLabel = new JLabel();
JLabel topicLabel = new JLabel();
JLabel userNameLabel = new JLabel();
JLabel privateField = new JLabel();
//text fields
usernameString = new JTextField(12);
topicIn = new JTextField(7);
newComment = new JTextField(3);
jobNumberOut = new JTextField(2);
//text Area
privateArea = new JTextArea(30, 30);
topicListModel = new DefaultListModel<>();
list = new JList(topicListModel);
allListModel = new DefaultListModel<>();
allDetailsList = new JList(allListModel);
selectTopicsModel = new DefaultListModel<>();
selectTopicsList = new JList(selectTopicsModel);
commentListModel = new DefaultListModel<>();
selectTopicsList = new JList(commentListModel);
newList = new JList();
topicStoreArea = new JList();
JScrollPane pane = new JScrollPane(list);
JScrollPane newListPane = new JScrollPane(newList);
JScrollPane addCommentPane = new JScrollPane(selectTopicsList);
jpanel3.add(topicStoreArea);
box = new JTextArea(30, 30);
//buttons
JButton getButton = new JButton();
JButton addTopicButton = new JButton();
JButton deleteTopicButton = new JButton();
JButton addCommentButton = new JButton();
jpanel3.add(box);
box.setEditable(false);
//set label text
topicLabel.setText("Topic ");
commentLabel.setText("Comment ");
privateField.setText("Private Field");
userNameLabel.setText("Username ");
getButton.setText(" Get ");
addTopicButton.setText("Post Topic");
deleteTopicButton.setText("Delete private content");
addCommentButton.setText("Add Comment");
topicIn.setText("");
newComment.setText("");
jobNumberOut.setText("");
jPanel2.add(topicLabel);
jPanel2.add(topicIn);
topicIn.setEditable(true);
jPanel2.add(commentLabel);
jPanel2.add(newComment);
newComment.setEditable(true);
jobNumberOut.setEditable(true);
jPanel1.add(jobNumberOut);
jPanel1.add(privateField);
jPanel1.add(userNameLabel);
currentUser = LoginPage.user.getUsername();
usernameString.setText(LoginPage.user.getUsername());
usernameString.setEditable(false);
jPanel1.add(usernameString);
/*topicPostArea.setCellRenderer(new ListCellRenderer<MRQueueTopicCreate>() {
@Override
public Component getListCellRendererComponent(JList list, MRQueueTopicCreate value, int index, boolean isSelected, boolean cellHasFocus) {
JLabel jLabel = new JLabel();
jLabel.setText( "[" + "User:" + " " + " - " + "Topic: " +
value.Topic + " - " + "Comment: " + value.Comment + "]" + "\n");
return jLabel;
}
});
topicPostArea.setModel(topicListModel);*/
//action performed
getButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
getSobj(evt);
}
});
addTopicButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
addTopic(evt);
}
});
deleteTopicButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
deleteTopic(evt);
}
});
addCommentButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
addComment(evt);
}
});
/*addNotificationButton.addListSelectionListener(e -> {
notify(); //add Notification
});*/
newList.addListSelectionListener(e -> {
if (hasRunMethod == false) {
// ViewTopicsPosts();
}
else{
hasRunMethod = true;
}
});
jPanel2.add(addTopicButton);
jPanel2.add(addCommentButton);
jPanel2.add(getButton);
jPanel2.add(deleteTopicButton);
cp.add(jPanel1, "North");
cp.add(jPanel2, "South");
cp.add(jpanel3, "East");
add(pane, BorderLayout.WEST);
add(newListPane, BorderLayout.CENTER);
add(addCommentPane, BorderLayout.NORTH);
//add(allListPane, BorderLayout.WEST);
// add(selectTopicsPane, BorderLayout.CENTER);
/*
list.addMouseListener(new MouseAdapter() {
@Override
public void mouseClicked(MouseEvent e) {
MRQueueTopicCreate template = new MRQueueTopicCreate();
MatchSet set = null;
try {
set = ((JavaSpace05) space).contents(Collections.singletonList(template), null, 1000 * 2, Long.MAX_VALUE);
MRQueueTopicCreate topic = null;
super.mouseClicked(e);
try {
topic = (MRQueueTopicCreate) set.next();
while (topic != null) {
if (e.getButton() == MouseEvent.NOBUTTON) {
//textArea.setText("No button clicked...");
topicListModel.addElement(topic);
topicListModel.addElement(MRHomePage.users);
}
}
} catch (RemoteException et) {
et.printStackTrace();
} catch (Exception et) {
et.printStackTrace();
}
}catch (Exception et) {
et.printStackTrace();
}
}
});
*/
}
//methods
public void addComment(java.awt.event.ActionEvent evt) {
String comment = newComment.getText();
String topic = topicIn.getText();
String userID = usernameString.getText();
try {
MRQueueCommentCreate topicLog = new MRQueueCommentCreate(comment,topic);
topicLog.setComment(comment);
topicLog.CommentUserId = userID;
topicLog.Comment = comment;
;
//ViewTopicsPosts();
MRQueueTopicCreate template = topicListModel.elementAt(list.getSelectedIndex());
topicListModel.getElementAt(list.getSelectedIndex());
topicLog.CommentUserId = LoginPage.user.getUsername();
//space.write(topicLog, null, Lease.FOREVER);
space.write( topicLog, null, Lease.FOREVER);
commentListModel.addElement(topicLog);
} catch (Exception e) {
e.printStackTrace();
}
allDetailsList.setModel(commentListModel);
}
public void deleteTopic(java.awt.event.ActionEvent evt) {
String comment = newComment.getText();
String topic = topicIn.getText();
String userID = usernameString.getText();
Integer bound1 = 0;
Integer bound2 = -1;
try {
MRQueueTopicCreate topicLog = new MRQueueTopicCreate(comment, topic, userID);
space.write(topicLog, null, Long.MAX_VALUE);
topicLog.setTopic(topic);
topicLog.setComment(comment);
space.write(topicLog, null, Lease.FOREVER);
//jobNumberOut.setText("" + topic);
// jobNameIn.setText("" + comment);
//if (template.owner = currentUser.username) {
//topicListModel.remove(list.getSelectedIndex());
MRQueueTopicCreate template = topicListModel.elementAt(list.getSelectedIndex());
MRQueueTopicCreate template1 = allListModel.elementAt(list.getSelectedIndex());
if(template.TopicUserID == LoginPage.user.getUsername())
{
topicListModel.remove(list.getSelectedIndex());
commentListModel.remove(list.getSelectedIndex());
//allListModel.remove(allDetailsList.getSelectedIndex());
System.out.println("user matches, topic removed");
}
else {
System.out.println("ugh");
}
space.take(template, null, 1000 * 2);
space.take(template1, null, 1000 * 2);
//}
} catch (Exception e) {
e.printStackTrace();
}
}
public void addTopic(java.awt.event.ActionEvent evt) {
//String comment = newComment.getText();
String comment = "";
String topic = topicIn.getText();
String userID = usernameString.getText();
try {
MRQueueTopicCreate topicLog = new MRQueueTopicCreate(comment, topic, userID);
topicLog.Topic = topic;
topicLog.Comment = comment;
topicLog.TopicUserID = userID;
MRQueueTopicCreate topicLogger = new MRQueueTopicCreate(comment, topic, userID);
topicLogger.Topic = topic;
//ViewTopicsPosts();
topicLog.TopicUserID = LoginPage.user.getUsername();
space.write(topicLog, null, Lease.FOREVER);
topicListModel.addElement(topicLog);
allListModel.addElement(topicLogger);
//allTopics.getItemAt(allTopics.getSelectedIndex());
//adds to the textfield on the left handside of the page
//box.append("[" + "User:" + " " + LoginPage.user.getUsername() + " - " + "Topic: " + topic + "]" + "\n");
//topicPostArea.append("[" + "User:" + " " + user + " - " + "Topic: " + topic + " - " + "Comment: " + comment + "]" + "\n");
} catch (Exception e) {
e.printStackTrace();
}
list.setModel(topicListModel);
//allDetailsList.setModel(allListModel);
}
public void getSobj(java.awt.event.ActionEvent evt) {
MRQueueTopicCreate template = new MRQueueTopicCreate();
MatchSet set = null;
try {
set = ((JavaSpace05) space).contents(Collections.singletonList(template), null, 1000 * 2, Long.MAX_VALUE);
MRQueueTopicCreate topic = null;
MRQueueTopicCreate got = (MRQueueTopicCreate) space.take(template, null, Lease.FOREVER);
if (got == null)
box.setText("No object found");
else if (list.isSelectedIndex(1))
{
}
else // use this to diplay all contents into the outstring textfield.
box.setText(got.getTopic());
} catch (Exception e) {
e.printStackTrace();
}
//newList.setModel(topicListModel);
}
public void startUP() {
JavaSpace space = SpaceUtils.getSpace();
if (space == null) {
System.err.println("Failed to find the javaspace");
System.exit(1);
}
QueueStatus template = new QueueStatus();
try {
QueueStatus returnedObject = (QueueStatus) space.readIfExists(template, null, ONESECOND);
if (returnedObject == null) {
// there is no object in the space, so create one
try {
QueueStatus qs = new QueueStatus(0);
space.write(qs, null, Lease.FOREVER);
System.out.println("QueueStatus object added to space");
System.exit(0);
} catch (Exception e) {
e.printStackTrace();
}
} else {
// there is already an object available, so don't create one
System.out.println("QueueStatus object is already in the space");
}
} catch (Exception e) {
e.printStackTrace();
}
}
/*public void ViewTopicsPosts() {
int selectedIndex = list.getSelectedIndex();
if (selectedIndex == -1) {
} else {
MRQueueTopicCreate topic = new MRQueueTopicCreate();
topic.Topic = topic.Topic;
topic.Comment = topic.Comment;
MatchSet set = null;
try {
set = ((JavaSpace05) space).contents(Collections.singletonList(topic), null, 1000 * 2, Long.MAX_VALUE);
MRQueueTopicCreate topicPosts = null;
try {
newList.clearSelection();
topicPosts = (MRQueueTopicCreate) set.next();
while (topicPosts != null) {
if (topic.TopicUserID.equals(LoginPage.user.userID)) {
newList.setModel(topicListModel);
topicListModel.addElement(topic);
topicListModel.addElement(MRHomePage.users);
}
else {
System.out.println("");
}
topicPosts = (MRQueueTopicCreate) set.next();
hasRunMethod = true;
}
} catch (RemoteException e){
e.printStackTrace();
}
} catch (Exception e) {
e.printStackTrace();
}
}
}*/
/* public void getAllTopics() {
MRQueueTopicCreate template = new MRQueueTopicCreate();
MatchSet set = null;
try {
set = ((JavaSpace05) space).contents(Collections.singletonList(template), null, 1000 * 2, Long.MAX_VALUE);
MRQueueTopicCreate topic = null;
try {
topic = (MRQueueTopicCreate) set.next();
while (topic != null) {
if (topic.TopicUserID.equals(LoginPage.user.userID)) {
topicListModel.addElement(topic);
topicListModel.addElement(MRHomePage.users);
newList.setModel(topicListModel);
} else {
topicListModel.addElement(topic);
}
}
} catch (RemoteException e) {
e.printStackTrace();
}
} catch (Exception e) {
e.printStackTrace();
}
//newList.setModel(topicListModel);
}*/
public void registerForEvents() {
}
@Override
public void notify(RemoteEvent remoteEvent) throws UnknownEventException, RemoteException {
//look for Gary's code on this
//the below code is from week 7 lecture notes
// this is the method called when we are notified
// of an object of interest
//Sobj template = new Sobj();
try {
// Sobj result = (Sobj)space.take(template, null, Long.MAX_VALUE);
//System.out.println(result.contents);
} catch (Exception e) {
e.printStackTrace();
}
// that's all we need to do in this demo so we can quit...
System.exit(0);
}
}