Source for java.lang.management.ManagementFactory

   1: /* ManagementFactory.java - Factory for obtaining system beans.
   2:    Copyright (C) 2006 Free Software Foundation
   3: 
   4: This file is part of GNU Classpath.
   5: 
   6: GNU Classpath is free software; you can redistribute it and/or modify
   7: it under the terms of the GNU General Public License as published by
   8: the Free Software Foundation; either version 2, or (at your option)
   9: any later version.
  10: 
  11: GNU Classpath is distributed in the hope that it will be useful, but
  12: WITHOUT ANY WARRANTY; without even the implied warranty of
  13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14: General Public License for more details.
  15: 
  16: You should have received a copy of the GNU General Public License
  17: along with GNU Classpath; see the file COPYING.  If not, write to the
  18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 USA.
  20: 
  21: Linking this library statically or dynamically with other modules is
  22: making a combined work based on this library.  Thus, the terms and
  23: conditions of the GNU General Public License cover the whole
  24: combination.
  25: 
  26: As a special exception, the copyright holders of this library give you
  27: permission to link this library with independent modules to produce an
  28: executable, regardless of the license terms of these independent
  29: modules, and to copy and distribute the resulting executable under
  30: terms of your choice, provided that you also meet, for each linked
  31: independent module, the terms and conditions of the license of that
  32: module.  An independent module is a module which is not derived from
  33: or based on this library.  If you modify this library, you may extend
  34: this exception to your version of the library, but you are not
  35: obligated to do so.  If you do not wish to do so, delete this
  36: exception statement from your version. */
  37: 
  38: package java.lang.management;
  39: 
  40: import gnu.classpath.SystemProperties;
  41: 
  42: import gnu.java.lang.management.ClassLoadingMXBeanImpl;
  43: import gnu.java.lang.management.CompilationMXBeanImpl;
  44: import gnu.java.lang.management.GarbageCollectorMXBeanImpl;
  45: import gnu.java.lang.management.OperatingSystemMXBeanImpl;
  46: import gnu.java.lang.management.MemoryMXBeanImpl;
  47: import gnu.java.lang.management.MemoryManagerMXBeanImpl;
  48: import gnu.java.lang.management.MemoryPoolMXBeanImpl;
  49: import gnu.java.lang.management.RuntimeMXBeanImpl;
  50: import gnu.java.lang.management.ThreadMXBeanImpl;
  51: 
  52: import java.util.ArrayList;
  53: import java.util.List;
  54: 
  55: import javax.management.NotCompliantMBeanException;
  56: 
  57: /**
  58:  * <p>
  59:  * Provides access to the system's management beans via a series
  60:  * of static methods.  
  61:  * </p>
  62:  * <p>
  63:  * An instance of a system management bean can be obtained by
  64:  * using one of the following methods:
  65:  * </p>
  66:  * <ol>
  67:  * <li>Calling the appropriate static method of this factory.
  68:  * </li>
  69:  * </ol>
  70:  *
  71:  * @author Andrew John Hughes (gnu_andrew@member.fsf.org)
  72:  * @since 1.5
  73:  */
  74: public class ManagementFactory
  75: {
  76: 
  77:   /**
  78:    * The operating system management bean.
  79:    */
  80:   private static OperatingSystemMXBean osBean;
  81: 
  82:   /**
  83:    * The runtime management bean.
  84:    */
  85:   private static RuntimeMXBean runtimeBean;
  86: 
  87:   /**
  88:    * The class loading management bean.
  89:    */
  90:   private static ClassLoadingMXBean classLoadingBean;
  91: 
  92:   /**
  93:    * The thread bean.
  94:    */
  95:   private static ThreadMXBean threadBean;
  96: 
  97:   /**
  98:    * The memory bean.
  99:    */
 100:   private static MemoryMXBean memoryBean;
 101: 
 102:   /**
 103:    * The compilation bean (may remain null).
 104:    */
 105:   private static CompilationMXBean compilationBean;
 106: 
 107:   /**
 108:    * Private constructor to prevent instance creation.
 109:    */
 110:   private ManagementFactory() {}
 111: 
 112:   /**
 113:    * Returns the operating system management bean for the
 114:    * operating system on which the virtual machine is running.
 115:    *
 116:    * @return an instance of {@link OperatingSystemMXBean} for
 117:    *         the underlying operating system.
 118:    */
 119:   public static OperatingSystemMXBean getOperatingSystemMXBean()
 120:   {
 121:     if (osBean == null)
 122:       try 
 123:     {
 124:       osBean = new OperatingSystemMXBeanImpl();
 125:     }
 126:       catch (NotCompliantMBeanException e)
 127:     {
 128:       throw new InternalError("The GNU implementation of the " +
 129:                   "operating system bean is not a " +
 130:                   "compliant management bean.");
 131:     }
 132:     return osBean;
 133:   }
 134: 
 135:   /**
 136:    * Returns the runtime management bean for the
 137:    * running virtual machine.
 138:    *
 139:    * @return an instance of {@link RuntimeMXBean} for
 140:    *         this virtual machine.
 141:    */
 142:   public static RuntimeMXBean getRuntimeMXBean()
 143:   {
 144:     if (runtimeBean == null)
 145:       try
 146:     {
 147:       runtimeBean = new RuntimeMXBeanImpl();
 148:     }
 149:       catch (NotCompliantMBeanException e)
 150:     {
 151:       throw new InternalError("The GNU implementation of the " +
 152:                   "runtime bean is not a compliant " +
 153:                   "management bean.");
 154:     }
 155:     return runtimeBean;
 156:   }
 157: 
 158:   /**
 159:    * Returns the class loading management bean for the
 160:    * running virtual machine.
 161:    *
 162:    * @return an instance of {@link ClassLoadingMXBean} for
 163:    *         this virtual machine.
 164:    */
 165:   public static ClassLoadingMXBean getClassLoadingMXBean()
 166:   {
 167:     if (classLoadingBean == null)
 168:       try
 169:     {
 170:       classLoadingBean = new ClassLoadingMXBeanImpl();
 171:     }
 172:       catch (NotCompliantMBeanException e)
 173:     {
 174:       throw new InternalError("The GNU implementation of the " +
 175:                   "class loading bean is not a " +
 176:                   "compliant management bean.");
 177:     }
 178:     return classLoadingBean;
 179:   }
 180: 
 181:   /**
 182:    * Returns the thread management bean for the running
 183:    * virtual machine.
 184:    *
 185:    * @return an instance of {@link ThreadMXBean} for
 186:    *         this virtual machine.
 187:    */
 188:   public static ThreadMXBean getThreadMXBean()
 189:   {
 190:     if (threadBean == null)
 191:       try
 192:     {
 193:       threadBean = new ThreadMXBeanImpl();
 194:     }
 195:       catch (NotCompliantMBeanException e)
 196:     {
 197:       throw new InternalError("The GNU implementation of the " +
 198:                   "thread bean is not a compliant " +
 199:                   "management bean.");
 200:     }
 201:     return threadBean;
 202:   }
 203: 
 204:   /**
 205:    * Returns the memory management bean for the running
 206:    * virtual machine.
 207:    *
 208:    * @return an instance of {@link MemoryMXBean} for
 209:    *         this virtual machine.
 210:    */
 211:   public static MemoryMXBean getMemoryMXBean()
 212:   {
 213:     if (memoryBean == null)
 214:       try
 215:     {
 216:       memoryBean = new MemoryMXBeanImpl();
 217:     }
 218:       catch (NotCompliantMBeanException e)
 219:     {
 220:       throw new InternalError("The GNU implementation of the " +
 221:                   "memory bean is not a compliant " +
 222:                   "management bean.");
 223:     }
 224:     return memoryBean;
 225:   }
 226: 
 227:   /**
 228:    * Returns the compilation bean for the running
 229:    * virtual machine, if supported.  Otherwise,
 230:    * it returns <code>null</code>.
 231:    *
 232:    * @return an instance of {@link CompilationMXBean} for
 233:    *         this virtual machine, or <code>null</code>
 234:    *         if the virtual machine doesn't include
 235:    *         a Just-In-Time (JIT) compiler.
 236:    */
 237:   public static CompilationMXBean getCompilationMXBean()
 238:   {
 239:     if (compilationBean == null &&
 240:     SystemProperties.getProperty("gnu.java.compiler.name") != null)
 241:       try
 242:     {
 243:       compilationBean = new CompilationMXBeanImpl();
 244:     }
 245:       catch (NotCompliantMBeanException e)
 246:     {
 247:       throw new InternalError("The GNU implementation of the " +
 248:                   "compilation bean is not a compliant " +
 249:                   "management bean.");
 250:     }
 251:     return compilationBean;
 252:   }
 253: 
 254:   /**
 255:    * Returns the memory pool beans for the running
 256:    * virtual machine.  These may change during the course
 257:    * of execution.
 258:    *
 259:    * @return a list of memory pool beans, one for each pool.
 260:    */
 261:   public static List getMemoryPoolMXBeans()
 262:   {
 263:     List poolBeans = new ArrayList();
 264:     String[] names = VMManagementFactory.getMemoryPoolNames();
 265:     for (int a = 0; a < names.length; ++a)
 266:       try
 267:     {
 268:       poolBeans.add(new MemoryPoolMXBeanImpl(names[a]));
 269:     }
 270:       catch (NotCompliantMBeanException e)
 271:     {
 272:       throw new InternalError("The GNU implementation of the " +
 273:                   "memory pool bean, " + a + ", is " +
 274:                   "not a compliant management bean.");
 275:     }
 276:     return poolBeans;
 277:   }
 278: 
 279:   /**
 280:    * Returns the memory manager beans for the running
 281:    * virtual machine.  These may change during the course
 282:    * of execution.
 283:    *
 284:    * @return a list of memory manager beans, one for each manager.
 285:    */
 286:   public static List getMemoryManagerMXBeans()
 287:   {
 288:     List managerBeans = new ArrayList();
 289:     String[] names = VMManagementFactory.getMemoryManagerNames();
 290:     for (int a = 0; a < names.length; ++a)
 291:       try
 292:     {
 293:       managerBeans.add(new MemoryManagerMXBeanImpl(names[a]));
 294:     }
 295:       catch (NotCompliantMBeanException e)
 296:     {
 297:       throw new InternalError("The GNU implementation of the " +
 298:                   "memory manager bean, " + a + ", is " +
 299:                   "not a compliant management bean.");
 300:     }
 301:     managerBeans.addAll(getGarbageCollectorMXBeans());
 302:     return managerBeans;
 303:   }
 304: 
 305:   /**
 306:    * Returns the garbage collector beans for the running
 307:    * virtual machine.  These may change during the course
 308:    * of execution.
 309:    *
 310:    * @return a list of garbage collector beans, one for each pool.
 311:    */
 312:   public static List getGarbageCollectorMXBeans()
 313:   {
 314:     List gcBeans = new ArrayList();
 315:     String[] names = VMManagementFactory.getGarbageCollectorNames();
 316:     for (int a = 0; a < names.length; ++a)
 317:       try
 318:     {
 319:       gcBeans.add(new GarbageCollectorMXBeanImpl(names[a]));
 320:     }
 321:       catch (NotCompliantMBeanException e)
 322:     {
 323:       throw new InternalError("The GNU implementation of the " +
 324:                   "garbage collector bean, " + a + 
 325:                   ", is not a compliant management " +
 326:                   "bean.");
 327:     }
 328:     return gcBeans;
 329:   }
 330: 
 331: }