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1
3
4 package org.jgroups.demos;
5
6
7 import org.jgroups.ChannelException;
8 import org.jgroups.ChannelFactory;
9 import org.jgroups.JChannelFactory;
10 import org.jgroups.blocks.DistributedHashtable;
11 import org.jgroups.persistence.PersistenceFactory;
12
13 import javax.swing.*;
14 import java.awt.*;
15 import java.awt.event.ActionEvent  ;
16 import java.awt.event.ActionListener ;
17 import java.awt.event.WindowEvent ;
18 import java.awt.event.WindowListener ;
19 import java.util.Enumeration ;
20 import java.util.Map ;
21 import java.util.Vector ;
22
23
24
25
26
33 public class DistributedHashtableDemo extends Frame implements WindowListener , ActionListener ,
34 DistributedHashtable.Notification {
35 static final String groupname="HashDemo";
36 DistributedHashtable h=null;
37 final JButton get=new JButton("Get");
38 final JButton set=new JButton("Set");
39 final JButton quit=new JButton("Quit");
40 final JButton get_all=new JButton("All");
41 final JButton delete=new JButton("Delete");
42 final JLabel stock=new JLabel("Key");
43 final JLabel value=new JLabel("Value");
44 final JLabel err_msg=new JLabel("Error");
45 final JTextField stock_field=new JTextField();
46 final JTextField value_field=new JTextField();
47 final java.awt.List listbox=new java.awt.List ();
48 final Font default_font=new Font("Helvetica", Font.PLAIN,12);
49
50
51
52
53 public DistributedHashtableDemo() {
54 super();
55 addWindowListener(this);
56 }
57
58 private void showMsg(String msg) {
59 err_msg.setText(msg);
60 err_msg.setVisible(true);
61 }
62
63 private void clearMsg() {err_msg.setVisible(false);}
64
65
66 private void removeItem() {
67 int index=listbox.getSelectedIndex();
68 if(index == -1) {
69 showMsg("No item selected in listbox to be deleted !");
70 return;
71 }
72 String s=listbox.getSelectedItem();
73 String key=s.substring(0, s.indexOf(':', 0));
74 if(key != null)
75 h.remove(key);
76 }
77
78 private void showAll() {
79 if(listbox.getItemCount() > 0)
80 listbox.removeAll();
81 if(h.size() == 0)
82 return;
83 clearMsg();
84 String key;
85 Float val;
86
87 for(Enumeration en=h.keys(); en.hasMoreElements();) {
88 key=(String )en.nextElement();
89 val=(Float )h.get(key);
90 if(val == null)
91 continue;
92 listbox.add(key + ": " + val.toString());
93 }
94 }
95
96
97
98
99
100 public void start(ChannelFactory factory, String props, boolean persist)
101 throws ChannelException {
102 h=new DistributedHashtable(groupname, factory, props, persist, 10000);
103 h.addNotifier(this);
104
105 setLayout(null);
106 setSize(400, 300);
107 setFont(default_font);
108
109 stock.setBounds(new Rectangle(10, 30, 60, 30));
110 value.setBounds(new Rectangle(10, 60, 60, 30));
111 stock_field.setBounds(new Rectangle(100, 30, 100, 30));
112 value_field.setBounds(new Rectangle(100, 60, 100, 30));
113 listbox.setBounds(new Rectangle(210, 30, 150, 160));
114 err_msg.setBounds(new Rectangle(10, 200, 350, 30));
115 err_msg.setFont(new Font("Helvetica",Font.ITALIC,12));
116 err_msg.setForeground(Color.red);
117 err_msg.setVisible(false);
118 get.setBounds(new Rectangle(10, 250, 60, 30));
119 set.setBounds(new Rectangle(80, 250, 60, 30));
120 quit.setBounds(new Rectangle(150, 250, 60, 30));
121 get_all.setBounds(new Rectangle(220, 250, 60, 30));
122 delete.setBounds(new Rectangle(290, 250, 80, 30));
123
124 get.addActionListener(this);
125 set.addActionListener(this);
126 quit.addActionListener(this);
127 get_all.addActionListener(this);
128 delete.addActionListener(this);
129
130 add(stock); add(value);
131 add(stock_field); add(value_field);
132 add(err_msg);
133 add(get); add(set); add(quit); add(get_all); add(delete);
134 add(listbox);
135 setTitle("DistributedHashtable Demo");
136 showAll();
137 pack();
138 setVisible(true);
139
140
141
150
155
158
159
160 }
161
162
163
164
165 public void windowActivated(WindowEvent e) {}
166 public void windowClosed(WindowEvent e) {}
167 public void windowClosing(WindowEvent e) {System.exit(0);}
168 public void windowDeactivated(WindowEvent e) {}
169 public void windowDeiconified(WindowEvent e) {}
170 public void windowIconified(WindowEvent e) {}
171 public void windowOpened(WindowEvent e) {}
172
173
174 public void actionPerformed(ActionEvent e) {
175 String command=e.getActionCommand();
176 try {
177 if(command == "Get") {
178 String stock_name=stock_field.getText();
179 if(stock_name == null || stock_name.length() == 0) {
180 showMsg("Key is empty !");
181 return;
182 }
183 showMsg("Looking up value for " + stock_name + ':');
184 Float val=(Float )h.get(stock_name);
185 if(val != null) {
186 value_field.setText(val.toString());
187 clearMsg();
188 }
189 else {
190 value_field.setText("");
191 showMsg("Value for " + stock_name + " not found");
192 }
193 }
194 else if(command == "Set") {
195 String stock_name=stock_field.getText();
196 String stock_val=value_field.getText();
197 if(stock_name == null || stock_val == null || stock_name.length() == 0 ||
198 stock_val.length() == 0) {
199 showMsg("Both key and value have to be present to create a new entry");
200 return;
201 }
202 Float val=new Float (stock_val);
203 h.put(stock_name, val);
204 showMsg("Key " + stock_name + " set to " + val);
205 }
206 else if(command == "All") {
207 showAll();
208 }
209 else if(command == "Quit") {
210 setVisible(false);
211 System.exit(0);
212 }
213 else if(command == "Delete")
214 removeItem();
215 else
216 System.out.println("Unknown action");
217 }
218 catch(Exception ex) {
219 value_field.setText("");
220 showMsg(ex.toString());
221 }
222 }
223
224
225
226 public void entrySet(Object key, Object value) {showAll();}
227
228 public void entryRemoved(Object key) {showAll();}
229
230 public void viewChange(Vector joined, Vector left) {
231 System.out.println("New members: " + joined + ", left members: " + left);
232 }
233
234 public void contentsSet(Map m) {
235 System.out.println("new contents: " + m);
236 }
237
238 public void contentsCleared() {
239 System.out.println("contents cleared");
240 }
241
242
243 public static void main(String args[]) {
244 DistributedHashtableDemo client=new DistributedHashtableDemo();
245 ChannelFactory factory=new JChannelFactory();
246 String arg;
247 boolean persist=false;
248
249
261
262 String props="UDP(mcast_addr=228.8.8.8;mcast_port=45566;ip_ttl=32;" +
263 "mcast_send_buf_size=150000;mcast_recv_buf_size=80000):" +
264 "PING(timeout=2000;num_initial_members=3):" +
265 "MERGE2(min_interval=5000;max_interval=10000):" +
266 "FD_SOCK:" +
267 "VERIFY_SUSPECT(timeout=1500):" +
268 "pbcast.NAKACK(gc_lag=50;retransmit_timeout=300,600,1200,2400,4800):" +
269 "UNICAST(timeout=5000):" +
270 "pbcast.STABLE(desired_avg_gossip=20000):" +
271 "FRAG(frag_size=4096;down_thread=false;up_thread=false):" +
272 "pbcast.GMS(join_timeout=5000;join_retry_timeout=2000;" +
273 "shun=false;print_local_addr=true):" +
274 "pbcast.STATE_TRANSFER";
275
276 try {
277 for(int i=0; i < args.length; i++) {
278 arg=args[i];
279 if("-persist".equals(arg) && i+1<args.length) {
280 persist=true;
281 PersistenceFactory.getInstance().createManager(args[++i]);
282 continue;
283 }
284 help();
285 return;
286 }
287 }
288 catch(Exception e) {
289 help();
290 return;
291 }
292 try {
293 client.start(factory, props, persist);
294 }
295 catch(Throwable t) {
296 t.printStackTrace();
297 }
298 }
299
300
301 static void help() {
302 System.out.println("DistributedHashtableDemo [-help] [-persist]");
303 }
304
305 }
306 |
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