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1
3 package org.jgroups.demos;
4
5
6 import org.jgroups.*;
7 import org.jgroups.blocks.GroupRequest;
8 import org.jgroups.blocks.RpcDispatcher;
9 import org.jgroups.util.Rsp;
10 import org.jgroups.util.RspList;
11
12 import java.awt.*;
13 import java.awt.event.ActionEvent  ;
14 import java.awt.event.ActionListener ;
15 import java.awt.event.WindowEvent ;
16 import java.awt.event.WindowListener ;
17 import java.util.Enumeration ;
18 import java.util.Hashtable ;
19
20
21
22
23
30 public class QuoteClient extends Frame implements WindowListener , ActionListener ,
31 MembershipListener {
32 static final String channel_name="Quotes";
33 RpcDispatcher disp;
34 Channel channel;
35 final Button get=new Button("Get");
36 final Button set=new Button("Set");
37 final Button quit=new Button("Quit");
38 final Button get_all=new Button("All");
39 final Label stock=new Label("Stock");
40 final Label value=new Label("Value");
41 final Label err_msg=new Label("Error");
42 final TextField stock_field=new TextField();
43 final TextField value_field=new TextField();
44 final java.awt.List listbox=new java.awt.List ();
45 final Font default_font=new Font("Helvetica", Font.PLAIN, 12);
46
49 final String props="UDP:" +
50 "PING(num_initial_members=2;timeout=3000):" +
51 "FD:" +
52 "pbcast.PBCAST(gossip_interval=5000;gc_lag=50):" +
53 "UNICAST:" +
54 "FRAG:" +
55 "pbcast.GMS:" +
56 "pbcast.STATE_TRANSFER";
57
58
59 public QuoteClient() {
60 super();
61 try {
62 channel=new JChannel(props);
63 channel.setOpt(Channel.LOCAL, Boolean.FALSE);
64 disp=new RpcDispatcher(channel, null, this, this);
65 channel.connect(channel_name);
66 }
67 catch(Exception e) {
68 System.err.println("QuoteClient(): " + e);
69 }
70 addWindowListener(this);
71 }
72
73 private void showMsg(String msg) {
74 err_msg.setText(msg);
75 err_msg.setVisible(true);
76 }
77
78 private void clearMsg() {
79 err_msg.setVisible(false);
80 }
81
82
83 public void start() {
84 setLayout(null);
85 setSize(400, 300);
86 setFont(default_font);
87
88 stock.setBounds(new Rectangle(10, 30, 60, 30));
89 value.setBounds(new Rectangle(10, 60, 60, 30));
90 stock_field.setBounds(new Rectangle(100, 30, 100, 30));
91 value_field.setBounds(new Rectangle(100, 60, 100, 30));
92 listbox.setBounds(210, 30, 150, 160);
93 err_msg.setBounds(new Rectangle(10, 200, 350, 30));
94 err_msg.setFont(new Font("Helvetica", Font.ITALIC, 12));
95 err_msg.setForeground(Color.red);
96 err_msg.setVisible(false);
97 get.setBounds(new Rectangle(10, 250, 80, 30));
98 set.setBounds(new Rectangle(100, 250, 80, 30));
99 quit.setBounds(new Rectangle(190, 250, 80, 30));
100 get_all.setBounds(new Rectangle(280, 250, 80, 30));
101
102 get.addActionListener(this);
103 set.addActionListener(this);
104 quit.addActionListener(this);
105 get_all.addActionListener(this);
106
107 add(stock);
108 add(value);
109 add(stock_field);
110 add(value_field);
111 add(err_msg);
112 add(get);
113 add(set);
114 add(quit);
115 add(get_all);
116 add(listbox);
117 setVisible(true);
119 }
120
121
122 public void windowActivated(WindowEvent e) {
123 }
124
125 public void windowClosed(WindowEvent e) {
126 }
127
128 public void windowClosing(WindowEvent e) {
129 System.exit(0);
130 }
131
132 public void windowDeactivated(WindowEvent e) {
133 }
134
135 public void windowDeiconified(WindowEvent e) {
136 }
137
138 public void windowIconified(WindowEvent e) {
139 }
140
141 public void windowOpened(WindowEvent e) {
142 }
143
144
145 public void actionPerformed(ActionEvent e) {
146 String command=e.getActionCommand();
147 RspList rsp_list;
148 Rsp first_rsp;
149
150 try {
151 if(command == "Get") {
152 String stock_name=stock_field.getText();
153 if(stock_name == null || stock_name.length() == 0) {
154 showMsg("Stock name is empty !");
155 return;
156 }
157 showMsg("Looking up value for " + stock_name + ':');
158 rsp_list=disp.callRemoteMethods(null, "getQuote", new Object []{stock_name},
159 new String []{String .class.getName()},
160 GroupRequest.GET_FIRST, 10000);
161
162 first_rsp=(Rsp)rsp_list.elementAt(0);
163 Float val=first_rsp != null? (Float )first_rsp.getValue() : null;
164 if(val != null) {
165 value_field.setText(val.toString());
166 clearMsg();
167 }
168 else {
169 value_field.setText("");
170 showMsg("Value for " + stock_name + " not found");
171 }
172 }
173 else
174 if(command == "Set") {
175 String stock_name=stock_field.getText();
176 String stock_val=value_field.getText();
177 if(stock_name == null || stock_val == null || stock_name.length() == 0 ||
178 stock_val.length() == 0) {
179 showMsg("Stock name and value have to be present to enter a new value");
180 return;
181 }
182 Float val=new Float (stock_val);
183 disp.callRemoteMethods(null, "setQuote", new Object []{stock_name, val},
184 new Class []{String .class, Float .class},
185 GroupRequest.GET_FIRST, 0);
186
187 showMsg("Stock " + stock_name + " set to " + val);
188 }
189 else
190 if(command == "All") {
191 listbox.removeAll();
192 showMsg("Getting all stocks:");
193 rsp_list=disp.callRemoteMethods(null, "printAllStocks",
194 (Object [])null, (Class [])null,
195 GroupRequest.GET_NONE, 0);
196
197 System.out.println("rsp_list is " + rsp_list);
198
199
200 Hashtable all_stocks=(Hashtable )rsp_list.getFirst();
201 if(all_stocks == null) {
202 showMsg("No stocks found");
203 return;
204 }
205 clearMsg();
206 listbox.removeAll();
207 String key;
208 Float val;
209 for(Enumeration en=all_stocks.keys(); en.hasMoreElements();) {
210 key=(String )en.nextElement();
211 val=(Float )all_stocks.get(key);
212 if(val == null)
213 continue;
214 listbox.add(key + ": " + val.toString());
215 }
216 }
217 else
218 if(command == "Quit") {
219 setVisible(false);
220 channel.close();
221 System.exit(0);
222 }
223 else
224 System.out.println("Unknown action");
225 }
226 catch(Exception ex) {
227 value_field.setText("");
228 ex.printStackTrace();
229 showMsg(ex.toString());
230 }
231 }
232
233
234 public void viewAccepted(View new_view) {
235 setTitle("Members in " + channel_name + ": " + (new_view.size() - 1));
236 }
237
238 public void suspect(Address suspected_mbr) {
239 }
240
241 public void block() {
242 }
243
244
245 public static void main(String args[]) {
246 QuoteClient client=new QuoteClient();
247 client.start();
248 }
249
250 }
251 |
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