001    /*
002     * CDDL HEADER START
003     *
004     * The contents of this file are subject to the terms of the
005     * Common Development and Distribution License, Version 1.0 only
006     * (the "License").  You may not use this file except in compliance
007     * with the License.
008     *
009     * You can obtain a copy of the license at
010     * trunk/opends/resource/legal-notices/OpenDS.LICENSE
011     * or https://OpenDS.dev.java.net/OpenDS.LICENSE.
012     * See the License for the specific language governing permissions
013     * and limitations under the License.
014     *
015     * When distributing Covered Code, include this CDDL HEADER in each
016     * file and include the License file at
017     * trunk/opends/resource/legal-notices/OpenDS.LICENSE.  If applicable,
018     * add the following below this CDDL HEADER, with the fields enclosed
019     * by brackets "[]" replaced with your own identifying information:
020     *      Portions Copyright [yyyy] [name of copyright owner]
021     *
022     * CDDL HEADER END
023     *
024     *
025     *      Copyright 2006-2008 Sun Microsystems, Inc.
026     */
027    package org.opends.server.monitors;
028    
029    
030    
031    import java.util.ArrayList;
032    import java.util.LinkedHashSet;
033    import java.util.Map;
034    import java.util.Map.Entry;
035    import java.util.TreeMap;
036    
037    import org.opends.server.admin.std.server.StackTraceMonitorProviderCfg;
038    import org.opends.server.api.MonitorProvider;
039    import org.opends.server.config.ConfigException;
040    import org.opends.server.core.DirectoryServer;
041    import org.opends.server.types.Attribute;
042    import org.opends.server.types.AttributeType;
043    import org.opends.server.types.AttributeValue;
044    import org.opends.server.types.InitializationException;
045    
046    
047    
048    /**
049     * This class defines a Directory Server monitor provider that can be used to
050     * obtain a stack trace from all server threads that are currently defined in
051     * the JVM.
052     */
053    public class StackTraceMonitorProvider
054           extends MonitorProvider<StackTraceMonitorProviderCfg>
055    {
056      /**
057       * Initializes this monitor provider.
058       */
059      public StackTraceMonitorProvider()
060      {
061        super("Stack Trace Monitor Provider");
062    
063        // No initialization should be performed here.
064      }
065    
066    
067    
068      /**
069       * {@inheritDoc}
070       */
071      public void initializeMonitorProvider(
072                       StackTraceMonitorProviderCfg configuration)
073             throws ConfigException, InitializationException
074      {
075        // No initialization is required.
076      }
077    
078    
079    
080      /**
081       * Retrieves the name of this monitor provider.  It should be unique among all
082       * monitor providers, including all instances of the same monitor provider.
083       *
084       * @return  The name of this monitor provider.
085       */
086      public String getMonitorInstanceName()
087      {
088        return "JVM Stack Trace";
089      }
090    
091    
092    
093      /**
094       * Retrieves the length of time in milliseconds that should elapse between
095       * calls to the <CODE>updateMonitorData()</CODE> method.  A negative or zero
096       * return value indicates that the <CODE>updateMonitorData()</CODE> method
097       * should not be periodically invoked.
098       *
099       * @return  The length of time in milliseconds that should elapse between
100       *          calls to the <CODE>updateMonitorData()</CODE> method.
101       */
102      public long getUpdateInterval()
103      {
104        // This monitor does not need to run periodically.
105        return 0;
106      }
107    
108    
109    
110      /**
111       * Performs any processing periodic processing that may be desired to update
112       * the information associated with this monitor.  Note that best-effort
113       * attempts will be made to ensure that calls to this method come
114       * <CODE>getUpdateInterval()</CODE> milliseconds apart, but no guarantees will
115       * be made.
116       */
117      public void updateMonitorData()
118      {
119        // This monitor does not need to run periodically.
120        return;
121      }
122    
123    
124    
125      /**
126       * Retrieves a set of attributes containing monitor data that should be
127       * returned to the client if the corresponding monitor entry is requested.
128       *
129       * @return  A set of attributes containing monitor data that should be
130       *          returned to the client if the corresponding monitor entry is
131       *          requested.
132       */
133      public ArrayList<Attribute> getMonitorData()
134      {
135        Map<Thread,StackTraceElement[]> threadStacks = Thread.getAllStackTraces();
136    
137    
138        // Re-arrange all of the elements by thread ID so that there is some logical
139        // order.
140        TreeMap<Long,Map.Entry<Thread,StackTraceElement[]>> orderedStacks =
141             new TreeMap<Long,Map.Entry<Thread,StackTraceElement[]>>();
142        for (Map.Entry<Thread,StackTraceElement[]> e : threadStacks.entrySet())
143        {
144          orderedStacks.put(e.getKey().getId(), e);
145        }
146    
147    
148        AttributeType attrType =
149             DirectoryServer.getDefaultAttributeType("jvmThread");
150        LinkedHashSet<AttributeValue> values = new LinkedHashSet<AttributeValue>();
151    
152        for (Map.Entry<Thread,StackTraceElement[]> e : orderedStacks.values())
153        {
154          Thread t                          = e.getKey();
155          StackTraceElement[] stackElements = e.getValue();
156    
157          long id = t.getId();
158    
159          StringBuilder buffer = new StringBuilder();
160          buffer.append("id=");
161          buffer.append(id);
162          buffer.append(" ---------- ");
163          buffer.append(t.getName());
164          buffer.append(" ----------");
165          values.add(new AttributeValue(attrType, buffer.toString()));
166    
167          // Create an attribute for the stack trace.
168          if (stackElements != null)
169          {
170            for (int j=0; j < stackElements.length; j++)
171            {
172              buffer = new StringBuilder();
173              buffer.append("id=");
174              buffer.append(id);
175              buffer.append(" frame[");
176              buffer.append(j);
177              buffer.append("]=");
178    
179              buffer.append(stackElements[j].getClassName());
180              buffer.append(".");
181              buffer.append(stackElements[j].getMethodName());
182              buffer.append("(");
183              buffer.append(stackElements[j].getFileName());
184              buffer.append(":");
185              if (stackElements[j].isNativeMethod())
186              {
187                buffer.append("native");
188              }
189              else
190              {
191                buffer.append(stackElements[j].getLineNumber());
192              }
193              buffer.append(")");
194    
195              values.add(new AttributeValue(attrType, buffer.toString()));
196            }
197          }
198        }
199    
200        ArrayList<Attribute> attrs = new ArrayList<Attribute>();
201        attrs.add(new Attribute(attrType, "jvmThread", values));
202    
203        return attrs;
204      }
205    }
206