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1
22 package org.jboss.ha.singleton;
23
24 import java.lang.reflect.InvocationTargetException  ;
25 import java.lang.reflect.Method ;
26 import java.security.InvalidParameterException ;
27
28 import javax.management.InstanceNotFoundException ;
29 import javax.management.MBeanException ;
30 import javax.management.ObjectName ;
31 import javax.management.ReflectionException ;
32
33
53 public class HASingletonController extends HASingletonSupport
54 implements HASingletonControllerMBean
55 {
56
58 private ObjectName mSingletonMBean;
59 private Object mSingleton;
60 private String mSingletonStartMethod = "startSingleton";
61 private String mSingletonStopMethod = "stopSingleton";
62 private String mSingletonStartMethodArgument;
63 private String mSingletonStopMethodArgument;
64
65 private static final Object [] NO_ARGS = new Object [0];
66 private static final String [] NO_TYPE_NAMES = new String [0];
67 private static final Class [] NO_TYPES = new Class [0];
68
69
71
74 public HASingletonController()
75 {
76 }
78
79
81 public Object getTarget()
82 {
83 return mSingleton;
84 }
85
86 public void setTarget(Object target)
87 {
88 this.mSingleton = target;
89 }
90
91 public ObjectName getTargetName()
92 {
93 return mSingletonMBean;
94 }
95
96 public void setTargetName(ObjectName targetObjectName)
97 {
98 this.mSingletonMBean = targetObjectName;
99 }
100
101 public String getTargetStartMethod()
102 {
103 return mSingletonStartMethod;
104 }
105
106 public void setTargetStartMethod(String targetStartMethod)
107 throws InvalidParameterException
108 {
109 if (targetStartMethod != null)
110 mSingletonStartMethod = targetStartMethod;
111 }
112
113
114 public String getTargetStopMethod()
115 {
116 return mSingletonStopMethod;
117 }
118
119 public void setTargetStopMethod(String targetStopMethod)
120 throws InvalidParameterException
121 {
122 if (targetStopMethod != null)
123 mSingletonStopMethod = targetStopMethod;
124 }
125
126 public String getTargetStartMethodArgument()
127 {
128 return mSingletonStartMethodArgument ;
129 }
130
131 public void setTargetStartMethodArgument(String targetStartMethodArgument)
132 {
133 mSingletonStartMethodArgument = targetStartMethodArgument;
134 }
135
136 public String getTargetStopMethodArgument()
137 {
138 return mSingletonStopMethodArgument ;
139 }
140
141 public void setTargetStopMethodArgument(String targetStopMethodArgument)
142 {
143 mSingletonStopMethodArgument = targetStopMethodArgument;
144 }
145
146
148
153 public void startSingleton()
154 {
155 super.startSingleton();
156
157 try
158 {
159 if (mSingleton != null)
160 {
161 invokeSingletonMethod(
162 mSingleton,
163 mSingletonStartMethod,
164 mSingletonStartMethodArgument
165 );
166 }
167 else if (mSingletonMBean != null)
168 {
169 invokeSingletonMBeanMethod(
170 mSingletonMBean,
171 mSingletonStartMethod,
172 mSingletonStartMethodArgument
173 );
174 }
175 else
176 {
177 log.warn("No singleton configured; cannot start");
178 }
179 }
180 catch (Exception e)
181 {
182 log.error("Controlled Singleton failed to become master", e);
183 }
184 }
185
186
191 public void stopSingleton()
192 {
193 super.stopSingleton();
194
195 try
196 {
197 if (mSingleton != null)
198 {
199 invokeSingletonMethod(
200 mSingleton,
201 mSingletonStopMethod,
202 mSingletonStopMethodArgument
203 );
204 }
205 else if (mSingletonMBean != null)
206 {
207 invokeSingletonMBeanMethod(
208 mSingletonMBean,
209 mSingletonStopMethod,
210 mSingletonStopMethodArgument
211 );
212 }
213 else
214 {
215 log.warn("No singleton configured; cannot start");
216 }
217 }
218 catch (Exception e)
219 {
220 log.error("Controlled Singleton failed to resign from master position", e);
221 }
222 }
223
224
226 protected Object invokeSingletonMethod(Object target,
227 String operationName, Object param)
228 throws IllegalAccessException , InvocationTargetException , NoSuchMethodException
229 {
230 if (target != null && operationName != null)
231 {
232 Object [] params;
233 Class [] types;
234
235 if (param != null)
236 {
237 params = new Object [] { param };
238 types = new Class [] { param.getClass() };
239
240 log.debug("Calling operation: " + operationName +
241 "(" + param + "), on target: '" + target + "'");
242 }
243 else
244 {
245 params = NO_ARGS;
246 types = NO_TYPES;
247
248 log.debug("Calling operation: " + operationName +
249 "(), on target: '" + target + "'");
250 }
251
252 Method method = getTargetMethod(target, operationName, types);
253
254 return method.invoke(target, params);
255 }
256 else
257 {
258 log.debug("No configured target mbean or operation to call");
259
260 return null;
261 }
262 }
263
264 protected Object invokeSingletonMBeanMethod(ObjectName target,
265 String operationName, Object param)
266 throws InstanceNotFoundException , MBeanException , ReflectionException
267 {
268 if (target != null && operationName != null)
269 {
270 Object [] params;
271 String [] signature;
272
273 if (param != null)
274 {
275 params = new Object [] { param };
276 signature = new String [] { param.getClass().getName() };
277
278 log.debug("Calling operation: " + operationName +
279 "(" + param + "), on target: '" + target + "'");
280 }
281 else
282 {
283 params = NO_ARGS;
284 signature = NO_TYPE_NAMES;
285
286 log.debug("Calling operation: " + operationName +
287 "(), on target: '" + target + "'");
288 }
289
290 return server.invoke(target, operationName, params, signature);
291 }
292 else
293 {
294 log.debug("No configured target mbean or operation to call");
295
296 return null;
297 }
298 }
299
300 public static Method getTargetMethod(Object target, String methodName, Class [] types)
301 throws NoSuchMethodException
302 {
303 Class clazz = target.getClass();
304 NoSuchMethodException nsme = null;
305 while (clazz != null)
306 {
307 try
308 {
309 Method method = clazz.getDeclaredMethod(methodName, types);
310 return method;
311 }
312 catch (NoSuchMethodException e)
313 {
314 if (nsme == null)
316 {
317 nsme = e;
318 }
319 clazz = clazz.getSuperclass();
321 }
322 }
323 throw nsme;
324 }
325 }
326 |
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