我正在尝试创建一个需要使用 JavaSpace 的聊天系统。在大多数情况下，这是有效的，除非尝试使自动通知正常工作，以便在添加条目时从空间向列表添加新条目时更新我的列表。当我收到 java.lang.ExceptionInInitializerError 时，这已成为一个问题。完整的跟踪输出如下。
Exception in thread "AWT-EventQueue-0" java.lang.ExceptionInInitializerError
at com.sun.jini.thread.GetThreadPoolAction.<clinit>(GetThreadPoolAction.java:52)
at net.jini.jeri.tcp.TcpServerEndpoint.<clinit>(TcpServerEndpoint.java:117)
at com.chat.client.gui.Topics.<init>(Topics.java:129)
at com.chat.client.gui.Main.actionPerformed(Main.java:114)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2028)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2351)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:242)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:236)
at java.awt.Component.processMouseEvent(Component.java:6382)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3275)
at java.awt.Component.processEvent(Component.java:6147)
at java.awt.Container.processEvent(Container.java:2083)
at java.awt.Component.dispatchEventImpl(Component.java:4744)
at java.awt.Container.dispatchEventImpl(Container.java:2141)
at java.awt.Component.dispatchEvent(Component.java:4572)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4619)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4280)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4210)
at java.awt.Container.dispatchEventImpl(Container.java:2127)
at java.awt.Window.dispatchEventImpl(Window.java:2489)
at java.awt.Component.dispatchEvent(Component.java:4572)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:704)
at java.awt.EventQueue.access$400(EventQueue.java:82)
at java.awt.EventQueue$2.run(EventQueue.java:663)
at java.awt.EventQueue$2.run(EventQueue.java:661)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:98)
at java.awt.EventQueue$3.run(EventQueue.java:677)
at java.awt.EventQueue$3.run(EventQueue.java:675)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:674)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:296)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:211)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:201)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:196)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:188)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)
Caused by: java.security.AccessControlException: access denied (java.lang.RuntimePermission modifyThreadGroup)
at java.security.AccessControlContext.checkPermission(AccessControlContext.java:374)
at java.security.AccessController.checkPermission(AccessController.java:549)
at java.lang.SecurityManager.checkPermission(SecurityManager.java:532)
at java.lang.SecurityManager.checkAccess(SecurityManager.java:712)
at java.lang.ThreadGroup.checkAccess(ThreadGroup.java:299)
at java.lang.ThreadGroup.getParent(ThreadGroup.java:150)
at com.sun.jini.thread.NewThreadAction$1.run(NewThreadAction.java:54)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.jini.thread.NewThreadAction.<clinit>(NewThreadAction.java:49)
... 40 more
我正在使用的代码如下
package com.chat.client.gui;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.rmi.RemoteException;
import java.util.ArrayList;
import javax.swing.DefaultComboBoxModel;
import javax.swing.JButton;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JScrollPane;
import javax.swing.JTextField;
import javax.swing.ListModel;
import javax.swing.WindowConstants;
import javax.swing.SwingUtilities;
import net.jini.core.entry.UnusableEntryException;
import net.jini.core.lease.Lease;
import net.jini.core.transaction.TransactionException;
import net.jini.space.JavaSpace;
import com.chat.client.backend.SpaceUtils;
import com.chat.client.backend.Topic;
import com.chat.client.backend.TopicList;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.DefaultListModel;
import net.jini.core.event.RemoteEvent;
import net.jini.core.event.RemoteEventListener
import java.rmi.server.*;
import java.rmi.RemoteException;
import net.jini.core.event.*;
import net.jini.export.Exporter;
import net.jini.jeri.BasicILFactory;
import net.jini.jeri.BasicJeriExporter;
import net.jini.jeri.tcp.TcpServerEndpoint;
import java.rmi.RMISecurityManager;
public class Topics extends javax.swing.JFrame implements ActionListener, RemoteEventListener {
private JList topicList;
private JScrollPane jScrollPane1;
private JButton exitButton;
private JButton closeButton;
private JButton joinTopic;
private JButton addButton;
private JLabel jLabel2;
private JLabel jLabel1;
private JTextField topicNameTextField;
/*
* user added variables
*/
private static JavaSpace space;
private String ownersName;
private String[] theTopics;
private boolean isFirstTimeStart = true;
private TopicList theList = null;
private TopicList template_list = null;
private ArrayList<String> topics;
private DefaultListModel topicListModel;
private RemoteEventListener theStub;
/**
* Auto-generated main method to display this JFrame
*/
public static void main(String[] args) throws RemoteException{
SwingUtilities.invokeLater(new Runnable() {
public void run() {
Topics inst = new Topics();
inst.setLocationRelativeTo(null);
inst.setVisible(true);
}
});
}
public Topics() {
super();
space = SpaceUtils.getSpace();
if (space == null){
System.err.println("Failed to find the javaspace");
System.exit(1);
}
try{
if (System.getSecurityManager() == null) {
System.setSecurityManager(new RMISecurityManager());
}
Exporter myDefaultExporter =
new BasicJeriExporter(TcpServerEndpoint.getInstance(0),
new BasicILFactory(), false, true);
} catch(Exception ex) {
}
initGUI();
}
public Topics(String s) {
super();
space = SpaceUtils.getSpace();
if (space == null){
System.err.println("Failed to find the javaspace");
System.exit(1);
}
try {
if (System.getSecurityManager() == null) {
System.setSecurityManager(new RMISecurityManager());
}
/*****The issue seems to arise here when instantiating the Exporter **********/
// create the exporter
Exporter myDefaultExporter =
new BasicJeriExporter(TcpServerEndpoint.getInstance(0),
new BasicILFactory(), false, true);
// register this as a remote object
// and get a reference to the 'stub'
theStub = (RemoteEventListener) myDefaultExporter.export(this);
// add the listener
space.notify(template_list, null, this.theStub, Lease.FOREVER, null);
ownersName = s; when using
topics = new ArrayList<String>();
topicListModel = new DefaultListModel();
template_list = null;
template_list = new TopicList();
System.out.println("trying to get the list from the space");
theList = null;
theList = (TopicList) space.take(template_list, null, Long.MAX_VALUE);
System.out.println("Got the list");
if(!theList.topics.isEmpty() && theList.topicListName.equals("GZSpace")) {
System.out.println("list is not empty");
for(int i = 0; i < theList.topics.size(); i++) {
topicListModel.addElement(theList.topics.get(i));
}
space.write(theList, null, Lease.FOREVER);
} else {
space.write(theList, null, Lease.FOREVER);
}
} catch (UnusableEntryException ex) {
Logger.getLogger(Topics.class.getName()).log(Level.SEVERE, null, ex);
} catch (TransactionException ex) {
Logger.getLogger(Topics.class.getName()).log(Level.SEVERE, null, ex);
} catch (InterruptedException ex) {
Logger.getLogger(Topics.class.getName()).log(Level.SEVERE, null, ex);
} catch (RemoteException ex) {
Logger.getLogger(Topics.class.getName()).log(Level.SEVERE, null, ex);
}
initGUI();
}
private void initGUI() {
try {
setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
getContentPane().setLayout(null);
{
jScrollPane1 = new JScrollPane();
getContentPane().add(jScrollPane1);
jScrollPane1.setBounds(230, 43, 142, 170);
{
topicList = new JList(topicListModel);
jScrollPane1.setViewportView(topicList);
topicList.setModel(topicListModel);
topicList.setBounds(230, 43, 142, 170);
}
}
{
topicNameTextField = new JTextField();
getContentPane().add(topicNameTextField);
topicNameTextField.setBounds(80, 43, 145, 23);
}
{
jLabel1 = new JLabel();
getContentPane().add(jLabel1);
jLabel1.setText("To create a topic, enter the name below and click add");
jLabel1.setBounds(12, 15, 355, 16);
}
{
jLabel2 = new JLabel();
getContentPane().add(jLabel2);
jLabel2.setText("Topic Name:");
jLabel2.setBounds(12, 46, 68, 16);
}
{
addButton = new JButton();
getContentPane().add(addButton);
addButton.setText("Add New " +
"Topic");
addButton.setBounds(12, 88, 213, 23);
addButton.addActionListener(this);
}
{
joinTopic = new JButton();
getContentPane().add(joinTopic);
joinTopic.setText("Join Existing Topic");
joinTopic.setBounds(12, 122, 213, 23);
joinTopic.addActionListener(this);
}
{
closeButton = new JButton();
getContentPane().add(closeButton);
closeButton.setText("Close ");
closeButton.setBounds(12, 156, 213, 23);
closeButton.addActionListener(this);
}
{
exitButton = new JButton();
getContentPane().add(exitButton);
exitButton.setText("Exit Chat System");
exitButton.setBounds(12, 190, 213, 23);
exitButton.addActionListener(this);
}
pack();
this.setSize(400, 269);
} catch (Exception e) {
//add your error handling code here
e.printStackTrace();
}
}
@Override
public void actionPerformed(ActionEvent e) {
if(e.getSource() == addButton) {
try {
theList = null;
template_list = null;
theList = (TopicList) space.take(template_list, null, Long.MAX_VALUE);
if(!theList.topics.isEmpty() && theList.topicListName.equals("GZSpace")) {
theList.topics.add(topicNameTextField.getText());
topicListModel.addElement(topicNameTextField.getText());
topicNameTextField.setText("");
space.write(theList, null, Lease.FOREVER);
} else {
space.write(theList, null, Lease.FOREVER);
}
} catch (UnusableEntryException ex) {
Logger.getLogger(Topics.class.getName()).log(Level.SEVERE, null, ex);
} catch (TransactionException ex) {
Logger.getLogger(Topics.class.getName()).log(Level.SEVERE, null, ex);
} catch (InterruptedException ex) {
Logger.getLogger(Topics.class.getName()).log(Level.SEVERE, null, ex);
} catch (RemoteException ex) {
Logger.getLogger(Topics.class.getName()).log(Level.SEVERE, null, ex);
}
}
if(e.getSource() == joinTopic) {
}
if(e.getSource() == closeButton) {
Main main = new Main();
main.setLocationRelativeTo(null);
main.setVisible(true);
dispose();
}
if(e.getSource() == exitButton) {
dispose();
}
}
public void notify(RemoteEvent ev) {
// this is the method called when we are notified
// of an object of interest
TopicList template = new TopicList();
try {
TopicList theList = (TopicList)space.take(template, null, Long.MAX_VALUE);
for(int i = 0; i < theList.topics.size(); i++) {
topicListModel.addElement(theList.topics.get(i));
}
} catch (Exception e) {
e.printStackTrace();
}
// that's all we need to do in this demo so we can quit...
System.exit(0);
}
}
谢天谢地，我们会收到任何帮助。