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1
46
47 package sample.simple.chat;
48
49 import java.io.IOException  ;
50
51 import org.mr.MantaAgentConstants;
52 import org.mr.api.simple.Message;
53 import org.mr.api.simple.MessageListener;
54 import org.mr.api.simple.Publisher;
55 import org.mr.api.simple.SimpleAPI;
56 import org.mr.api.simple.SimpleException;
57 import org.mr.api.simple.Subscriber;
58
59
63
64
73 public class Chat implements MessageListener {
74 private Publisher publisher;
75 private Subscriber subscriber;
76
77 public Chat(Publisher publisher, Subscriber subscriber)
78 throws SimpleException
79 {
80 this.publisher = publisher;
81 this.subscriber = subscriber;
82 this.subscriber.subscribe(this);
83 }
84
85 public void go() {
86 try {
88 while (true) {
89 StringBuffer text = new StringBuffer ();
90 int c;
91 boolean shouldExit = false;
92
93 System.out.print("chat> ");
95 while ((c = System.in.read()) != (int) '\n') {
96 if (c == -1) { System.out.println();
98 System.out.println("Goodbye.");
99 shouldExit = true;
100 } else {
101 text.append((char) c);
102 }
103 }
104
105 if (shouldExit) break;
107 Message message = new Message(text.toString().getBytes());
108 this.publisher.send(message);
109 }
110 } catch (SimpleException e) {
111 System.err.println("Exception thrown in send loop: " + e);
112 System.err.println("Exiting...");
113 } catch (IOException e) {
114 System.err.println("I/O Error while reading from stdin: " + e);
115 System.err.println("Exiting...");
116 }
117 }
118
119 public void onMessage(Message message, String topicName) {
120 String text = new String (message.getPayload());
122 System.out.println();
123 System.out.println("> " + text);
124 System.out.print("chat> ");
125 }
126
127 public static String topicName;
128 public static String mantaConf;
129
130 public static void main(String args[]) {
131 parseArgs(args);
132
133 try {
134 SimpleAPI api = new SimpleAPI(mantaConf);
136 Publisher publisher = api.openPublisher(topicName);
137 Subscriber subscriber = api.openSubscriber(topicName);
138
139 Chat chat = new Chat(publisher, subscriber);
141
142 chat.go();
144 } catch (SimpleException e) {
145 System.err.println("Exception thrown while initializing: " + e);
146 System.err.println("Exiting...");
147 }
148 System.exit(0);
149 }
150
151 private static void parseArgs(String [] args) {
152 for (int i = 0; i < args.length; i++) {
153 String arg = args[i];
154 if (!arg.startsWith("-")) {
155 System.err.println("error: unexpected argument -- " + arg);
156 printUsage();
157 System.exit(1);
158 } else {
159 if (arg.equals("-c")) {
160 if (i == args.length - 1 || args[i+1].startsWith("-")) {
161 System.err.println("error: missing config-dir " +
162 "argument");
163 printUsage();
164 System.exit(1);
165 }
166 mantaConf = args[++i];
167 continue;
168 } else if (arg.equals("-t")) {
169 if (i == args.length - 1 || args[i+1].startsWith("-")) {
170 System.err.println("error: missing topic argument");
171 printUsage();
172 System.exit(1);
173 }
174 topicName = args[++i];
175 continue;
176 } else if (arg.equals("-h")) {
177 printUsage();
178 System.exit(1);
179 } else {
180 System.err.println("unrecognized option -- " + arg);
181 }
182 }
183 }
184
185 if(mantaConf == null){
186 mantaConf = System.getProperty(MantaAgentConstants.MANTA_CONFIG);
187 }
188 if (mantaConf == null) {
189 mantaConf = "./default_config.xml";
190 }
191 if (topicName == null) {
192 System.err.println("error: you did not specify a topic");
193 System.exit(1);
194 }
195 }
196
197 private static void printUsage() {
198 System.out.println("Usage: java Chat -c <config-dir> -t <topic>");
199 System.out.println("\t-c config-dir\tmanta installation dir, should " +
200 "contain manta.jar");
201 System.out.println("\t-t topic\ttopic name used for sending and " +
202 "receiving messages");
203 }
204
205 } |
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