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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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package org.jgroups.demos;


import org.jgroups.*;
import org.jgroups.blocks.RequestOptions;
import org.jgroups.blocks.ResponseMode;
import org.jgroups.blocks.RpcDispatcher;
import org.jgroups.util.Rsp;
import org.jgroups.util.RspList;

import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;
import java.util.Enumeration;
import java.util.Hashtable;


/**
 * Used in conjunction with QuoteServer: a client is member of a group of quote servers which replicate
 * stock quotes among themselves. The client broadcasts its request (set, get quotes) and (in the case of get
 * waits for the first reply received (usually the one from the quote server closest to it). The client
 * can get and set quotes as long as a minimum of 1 server (in the group) is running.
 * @author Bela Ban
 */
public class QuoteClient extends Frame implements WindowListener, ActionListener,
        MembershipListener {
    static final String channel_name="Quotes";
    RpcDispatcher disp;
    Channel channel;
    final Button get=new Button("Get");
    final Button set=new Button("Set");
    final Button quit=new Button("Quit");
    final Button get_all=new Button("All");
    final Label stock=new Label("Stock");
    final Label value=new Label("Value");
    final Label err_msg=new Label("Error");
    final TextField stock_field=new TextField();
    final TextField value_field=new TextField();
    final java.awt.List listbox=new java.awt.List();
    final Font default_font=new Font("Helvetica", Font.PLAIN, 12);

    static final String props=null; // default stack from JChannel


    public QuoteClient() {
        super();
        try {
            channel=new JChannel(props);
            channel.setDiscardOwnMessages(true);
            disp=new RpcDispatcher(channel, null, this, this);
            channel.connect(channel_name);
        }
        catch(Exception e) {
            System.err.println("QuoteClient(): " + e);
        }
        addWindowListener(this);
    }

    private void showMsg(String msg) {
        err_msg.setText(msg);
        err_msg.setVisible(true);
    }

    private void clearMsg() {
        err_msg.setVisible(false);
    }


    public void start() {
        setLayout(null);
        setSize(400, 300);
        setFont(default_font);

        stock.setBounds(new Rectangle(10, 30, 60, 30));
        value.setBounds(new Rectangle(10, 60, 60, 30));
        stock_field.setBounds(new Rectangle(100, 30, 100, 30));
        value_field.setBounds(new Rectangle(100, 60, 100, 30));
        listbox.setBounds(210, 30, 150, 160);
        err_msg.setBounds(new Rectangle(10, 200, 350, 30));
        err_msg.setFont(new Font("Helvetica", Font.ITALIC, 12));
        err_msg.setForeground(Color.red);
        err_msg.setVisible(false);
        get.setBounds(new Rectangle(10, 250, 80, 30));
        set.setBounds(new Rectangle(100, 250, 80, 30));
        quit.setBounds(new Rectangle(190, 250, 80, 30));
        get_all.setBounds(new Rectangle(280, 250, 80, 30));

        get.addActionListener(this);
        set.addActionListener(this);
        quit.addActionListener(this);
        get_all.addActionListener(this);

        add(stock);
        add(value);
        add(stock_field);
        add(value_field);
        add(err_msg);
        add(get);
        add(set);
        add(quit);
        add(get_all);
        add(listbox);
        // stock_field.requestFocus();
        setVisible(true);
    }


    public void windowActivated(WindowEvent e) {
    }

    public void windowClosed(WindowEvent e) {
    }

    public void windowClosing(WindowEvent e) {
        System.exit(0);
    }

    public void windowDeactivated(WindowEvent e) {
    }

    public void windowDeiconified(WindowEvent e) {
    }

    public void windowIconified(WindowEvent e) {
    }

    public void windowOpened(WindowEvent e) {
    }


    public void actionPerformed(ActionEvent e) {
        String command=e.getActionCommand();

        try {
            if(command.equals("Get")) {
                String stock_name=stock_field.getText();
                if(stock_name == null || stock_name.length() == 0) {
                    showMsg("Stock name is empty !");
                    return;
                }
                showMsg("Looking up value for " + stock_name + ':');
                RspList quotes=disp.callRemoteMethods(null, "getQuote", new Object[]{stock_name},
                                                               new Class[]{String.class},
                                                               new RequestOptions(ResponseMode.GET_ALL, 10000));

                Float val=null;
                for(Rsp rsp: quotes.values()) {
                    Object quote=rsp.getValue();
                    if(quote == null || quote instanceof Throwable)
                        continue;
                    val=(Float)quote;
                    break;
                }

                if(val != null) {
                    value_field.setText(val.toString());
                    clearMsg();
                }
                else {
                    value_field.setText("");
                    showMsg("Value for " + stock_name + " not found");
                }
            }
            else
                if(command.equals("Set")) {
                    String stock_name=stock_field.getText();
                    String stock_val=value_field.getText();
                    if(stock_name == null || stock_val == null || stock_name.length() == 0 ||
                            stock_val.length() == 0) {
                        showMsg("Stock name and value have to be present to enter a new value");
                        return;
                    }
                    Float val=new Float(stock_val);
                    disp.callRemoteMethods(null, "setQuote", new Object[]{stock_name, val},
                                           new Class[]{String.class, Float.class},
                                           new RequestOptions(ResponseMode.GET_FIRST, 0));

                    showMsg("Stock " + stock_name + " set to " + val);
                }
                else
                    if(command.equals("All")) {
                        listbox.removeAll();
                        showMsg("Getting all stocks:");
                        RspList rsp_list=disp.callRemoteMethods(null, "getAllStocks",
                                                                        null, null,
                                                                        new RequestOptions(ResponseMode.GET_ALL, 5000));

                        System.out.println("rsp_list is " + rsp_list);

                        Hashtable all_stocks=null;
                        for(Rsp rsp: rsp_list.values()) {
                            Object obj=rsp.getValue();
                            if(obj == null || obj instanceof Throwable)
                                continue;
                            all_stocks=(Hashtable)obj;
                            break;
                        }

                        if(all_stocks == null) {
                            showMsg("No stocks found");
                            return;
                        }
                        clearMsg();
                        listbox.removeAll();
                        String key;
                        Float val;
                        for(Enumeration en=all_stocks.keys(); en.hasMoreElements();) {
                            key=(String)en.nextElement();
                            val=(Float)all_stocks.get(key);
                            if(val == null)
                                continue;
                            listbox.add(key + ": " + val.toString());
                        }
                    }
                    else
                        if(command.equals("Quit")) {
                            setVisible(false);
                            channel.close();
                            System.exit(0);
                        }
                        else
                            System.out.println("Unknown action");
        }
        catch(Exception ex) {
            value_field.setText("");
            ex.printStackTrace();
            showMsg(ex.toString());
        }
    }



    public void setQuote(String stock_name, Float value) {
        ;
    }

    public void printAllStocks() {
    }


    public void viewAccepted(View new_view) {
        setTitle("Members in " + channel_name + ": " + (new_view.size() - 1));
    }

    public void suspect(Address suspected_mbr) {
    }

    public void block() {
    }

    public void unblock() {
    }

    public static void main(String args[]) {
        QuoteClient client=new QuoteClient();
        client.start();
    }

}
 















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