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1
3 package org.jgroups.demos.applets;
4
5 import java.applet.Applet  ;
6 import java.awt.*;
7 import java.awt.event.ActionEvent ;
8 import java.awt.event.ActionListener ;
9 import java.awt.event.MouseEvent ;
10 import java.awt.event.MouseMotionListener ;
11 import java.io.ByteArrayInputStream ;
12 import java.io.ByteArrayOutputStream ;
13 import java.io.DataInputStream ;
14 import java.io.DataOutputStream ;
15 import java.util.Random ;
16 import java.util.Vector ;
17 import org.jgroups.*;
18
19
20
21
22 public class DrawApplet extends Applet implements Runnable , MouseMotionListener , ActionListener {
23 private Graphics graphics=null;
24 private Panel panel=null, sub_panel=null;
25 private final ByteArrayOutputStream out=new ByteArrayOutputStream ();
26 private DataOutputStream outstream;
27 private DataInputStream instream;
28 private final Random random=new Random (System.currentTimeMillis());
29 private Button clear_button, leave_button;
30 private Label mbr_label;
31 private final Font default_font=new Font("Helvetica",Font.PLAIN,12);
32 private final String groupname="DrawGroup";
33 private Channel channel=null;
34 private Thread receiver=null;
35 private int member_size=1;
36 private int red=0, green=0, blue=0;
37 private Color default_color=null;
38
39 private final ChannelFactory factory=new JChannelFactory();
40 private String props="TUNNEL(router_host=janet;router_port=12002):" +
41 "PING(gossip_host=janet;gossip_port=12002):" +
42 "FD:STABLE:NAKACK:UNICAST:FRAG:FLUSH:GMS:VIEW_ENFORCER:QUEUE";
43
44 private final Vector members=new Vector ();
45 private boolean fl=true;
46
47
48
49
50
51 public void init() {
52 System.out.println("INIT");
53 setLayout(new BorderLayout());
54
55 String tmp_props=getParameter("properties");
56 if(tmp_props != null) {
57 System.out.println("Setting parameters " + tmp_props);
58 props=tmp_props;
59 }
60
61
62 try {
63 channel=factory.createChannel(props);
64 showStatus("Connecting to group " + groupname);
65 channel.connect(groupname);
66 }
67 catch(Exception e) {
68 System.err.println(e);
69 }
70 receiver=new Thread (this, "DrawThread");
71 receiver.start();
72 go();
73 }
74
75
76
77 public void start() {
78 System.out.println("------- START");
79 }
80
81
82
83
84
85 public void destroy() {
86 System.out.println("------- DESTROY");
87
88 if(receiver != null && receiver.isAlive()) {
89 fl=false;
90 receiver.interrupt();
91 try {receiver.join(1000);} catch(Exception ex) {}
92 }
93 receiver=null;
94 showStatus("Disconnecting from " + groupname);
95 channel.disconnect();
96 showStatus("Disconnected");
97 }
98
99
100 public void paint(Graphics g) {
101 Rectangle bounds=panel.getBounds();
102 Color old=graphics.getColor();
103
104 if(bounds == null || graphics == null)
105 return;
106
107 graphics.setColor(Color.black);
108 graphics.drawRect(0, 0, bounds.width-1, bounds.height-1);
109 graphics.setColor(old);
110 }
111
112
113 private void selectColor() {
114 red=(Math.abs(random.nextInt()) % 255);
115 green=(Math.abs(random.nextInt()) % 255);
116 blue=(Math.abs(random.nextInt()) % 255);
117 default_color=new Color(red, green, blue);
118 }
119
120
121
122
123 public void go() {
124 try {
125 panel=new Panel();
126 sub_panel=new Panel();
127 resize(200, 200);
128 add("Center", panel);
129 clear_button=new Button("Clear");
130 clear_button.setFont(default_font);
131 clear_button.addActionListener(this);
132 leave_button=new Button("Exit");
133 leave_button.setFont(default_font);
134 leave_button.addActionListener(this);
135 mbr_label=new Label("0 mbr(s)");
136 mbr_label.setFont(default_font);
137 sub_panel.add("South", clear_button);
138 sub_panel.add("South", leave_button);
139 sub_panel.add("South", mbr_label);
140 add("South", sub_panel);
141 panel.addMouseMotionListener(this);
142 setVisible(true);
143 mbr_label.setText(member_size + " mbrs");
144 graphics=panel.getGraphics();
145 selectColor();
146 graphics.setColor(default_color);
147 panel.setBackground(Color.white);
148 clear_button.setForeground(Color.blue);
149 leave_button.setForeground(Color.blue);
150 }
151 catch(Exception e) {
152 System.err.println(e);
153 return;
154 }
155 }
156
157
158 public void run() {
159 Object tmp;
160 Message msg=null;
161 int my_x=10, my_y=10, r=0, g=0, b=0;
162
163
164 while(fl) {
165 my_x=10;
166 my_y=10;
167 try {
168 tmp=channel.receive(0);
169 if(tmp instanceof View) {
170 viewAccepted((View)tmp);
171 continue;
172 }
173 if(!(tmp instanceof Message))
174 continue;
175 msg=(Message)tmp;
176
177 if(msg == null || msg.getLength() == 0) {
178 System.err.println("DrawApplet.run(): msg or msg.buffer is null !");
179 continue;
180 }
181
182 instream=new DataInputStream (new ByteArrayInputStream (msg.getRawBuffer(), msg.getOffset(), msg.getLength()));
183 r=instream.readInt(); if(r == -13) {
185 clearPanel();
186 continue;
187 }
188 g=instream.readInt(); b=instream.readInt(); my_x=instream.readInt();
191 my_y=instream.readInt();
192 }
193 catch(ChannelNotConnectedException conn) {
194 break;
195 }
196 catch(Exception e) {
197 System.err.println(e);
198 }
199 if(graphics != null) {
200 graphics.setColor(new Color(r, g, b));
201 graphics.fillOval(my_x, my_y, 10, 10);
202 graphics.setColor(default_color);
203 }
204 }
205 }
206
207
208
209
210
211 public void mouseMoved(MouseEvent e) {}
212
213 public void mouseDragged(MouseEvent e) {
214 int tmp[]=new int[1], x, y;
215
216 tmp[0]=0;
217 x=e.getX();
218 y=e.getY();
219
220 graphics.fillOval(x, y, 10, 10);
221
222 try {
223 out.reset();
224 outstream=new DataOutputStream (out);
225 outstream.writeInt(red);
226 outstream.writeInt(green);
227 outstream.writeInt(blue);
228 outstream.writeInt(x);
229 outstream.writeInt(y);
230 channel.send(new Message(null, null, out.toByteArray()));
231 out.reset();
232 }
233 catch(Exception ex) {
234 System.err.println(ex);
235 }
236 }
237
238
239 public void clearPanel() {
240 Rectangle bounds=null;
241 if(panel == null || graphics == null)
242 return;
243
244 bounds=panel.getBounds();
245 graphics.clearRect(1, 1, bounds.width-2, bounds.height-2);
246
247
248 }
249
250
251 public void sendClearPanelMsg() {
252 int tmp[]=new int[1]; tmp[0]=0;
253
254 clearPanel();
255
256 try {
257 out.reset();
258 outstream=new DataOutputStream (out);
259 outstream.writeInt(-13);
260 channel.send(new Message(null, null, out.toByteArray()));
261 outstream.flush();
262 }
263 catch(Exception ex) {
264 System.err.println(ex);
265 }
266 }
267
268
269
270
271 public void actionPerformed(ActionEvent e) {
272 String command=e.getActionCommand();
273 if(command == "Clear") {
274 System.out.println("Members are " + members);
275 sendClearPanelMsg();
276 }
277 else if(command == "Exit") {
278 try {
279 destroy();
280 setVisible(false);
281 }
282 catch(Exception ex) {
283 System.err.println(ex);
284 }
285
286 }
287 else
288 System.out.println("Unknown action");
289 }
290
291
292 public void viewAccepted(View v) {
293 Vector mbrs=v.getMembers();
294 if(v != null) {
295 System.out.println("View accepted: " +v);
296 member_size=v.size();
297
298 if(mbr_label != null)
299 mbr_label.setText(member_size + " mbr(s)");
300
301 members.removeAllElements();
302 for(int i=0; i < mbrs.size(); i++)
303 members.addElement(mbrs.elementAt(i));
304 }
305 }
306
307
308
309
310
311 }
312
313 |
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