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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
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 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
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package sun.management.snmp.jvminstr;

// java imports
//
import com.sun.jmx.mbeanserver.Util;
import java.util.List;
import java.util.Map;

// jmx imports
//
import javax.management.MBeanServer;
import javax.management.ObjectName;
import com.sun.jmx.snmp.SnmpCounter;
import com.sun.jmx.snmp.SnmpCounter64;
import com.sun.jmx.snmp.SnmpGauge;
import com.sun.jmx.snmp.SnmpInt;
import com.sun.jmx.snmp.SnmpUnsignedInt;
import com.sun.jmx.snmp.SnmpIpAddress;
import com.sun.jmx.snmp.SnmpTimeticks;
import com.sun.jmx.snmp.SnmpOpaque;
import com.sun.jmx.snmp.SnmpString;
import com.sun.jmx.snmp.SnmpStringFixed;
import com.sun.jmx.snmp.SnmpOid;
import com.sun.jmx.snmp.SnmpNull;
import com.sun.jmx.snmp.SnmpValue;
import com.sun.jmx.snmp.SnmpVarBind;
import com.sun.jmx.snmp.SnmpStatusException;

// jdmk imports
//
import com.sun.jmx.snmp.agent.SnmpIndex;
import com.sun.jmx.snmp.agent.SnmpMib;
import com.sun.jmx.snmp.agent.SnmpMibTable;
import com.sun.jmx.snmp.agent.SnmpMibSubRequest;
import com.sun.jmx.snmp.agent.SnmpStandardObjectServer;

import sun.management.snmp.jvmmib.JvmRTClassPathTableMeta;
import sun.management.snmp.util.SnmpCachedData;
import sun.management.snmp.util.SnmpTableCache;
import sun.management.snmp.util.SnmpTableHandler;
import sun.management.snmp.util.MibLogger;
import sun.management.snmp.util.JvmContextFactory;

The class is used for implementing the "JvmRTClassPathTable".
/** * The class is used for implementing the "JvmRTClassPathTable". */
public class JvmRTClassPathTableMetaImpl extends JvmRTClassPathTableMeta { private SnmpTableCache cache;
A concrete implementation of SnmpTableCache, for the JvmRTClassPathTable.
/** * A concrete implementation of {@link SnmpTableCache}, for the * JvmRTClassPathTable. **/
private static class JvmRTClassPathTableCache extends SnmpTableCache { private JvmRTClassPathTableMetaImpl meta; JvmRTClassPathTableCache(JvmRTClassPathTableMetaImpl meta, long validity) { this.meta = meta; this.validity = validity; }
Call getTableDatas(JvmContextFactory.getUserData()).
/** * Call <code>getTableDatas(JvmContextFactory.getUserData())</code>. **/
public SnmpTableHandler getTableHandler() { final Map userData = JvmContextFactory.getUserData(); return getTableDatas(userData); }
Return a table handler containing the Thread indexes. Indexes are computed from the ThreadId.
/** * Return a table handler containing the Thread indexes. * Indexes are computed from the ThreadId. **/
protected SnmpCachedData updateCachedDatas(Object userData) { // We are getting all the input args final String[] path = JvmRuntimeImpl.getClassPath(userData); // Time stamp for the cache final long time = System.currentTimeMillis(); final int len = path.length; SnmpOid indexes[] = new SnmpOid[len]; for(int i = 0; i < len; i++) { indexes[i] = new SnmpOid(i + 1); } return new SnmpCachedData(time, indexes, path); } }
Constructor for the table. Initialize metadata for "JvmRTClassPathTableMeta". The reference on the MBean server is updated so the entries created through an SNMP SET will be AUTOMATICALLY REGISTERED in Java DMK.
/** * Constructor for the table. Initialize metadata for * "JvmRTClassPathTableMeta". * The reference on the MBean server is updated so the entries * created through an SNMP SET will be AUTOMATICALLY REGISTERED * in Java DMK. */
public JvmRTClassPathTableMetaImpl(SnmpMib myMib, SnmpStandardObjectServer objserv) { super(myMib, objserv); cache = new JvmRTClassPathTableCache(this, -1); } // See com.sun.jmx.snmp.agent.SnmpMibTable protected SnmpOid getNextOid(Object userData) throws SnmpStatusException { // null means get the first OID. return getNextOid(null,userData); } // See com.sun.jmx.snmp.agent.SnmpMibTable protected SnmpOid getNextOid(SnmpOid oid, Object userData) throws SnmpStatusException { final boolean dbg = log.isDebugOn(); if (dbg) log.debug("getNextOid", "previous=" + oid); // Get the data handler. // SnmpTableHandler handler = getHandler(userData); if (handler == null) { // This should never happen. // If we get here it's a bug. // if (dbg) log.debug("getNextOid", "handler is null!"); throw new SnmpStatusException(SnmpStatusException.noSuchInstance); } // Get the next oid // final SnmpOid next = handler.getNext(oid); if (dbg) log.debug("*** **** **** **** getNextOid", "next=" + next); // if next is null: we reached the end of the table. // if (next == null) throw new SnmpStatusException(SnmpStatusException.noSuchInstance); return next; } // See com.sun.jmx.snmp.agent.SnmpMibTable protected boolean contains(SnmpOid oid, Object userData) { // Get the handler. // SnmpTableHandler handler = getHandler(userData); // handler should never be null. // if (handler == null) return false; return handler.contains(oid); } // See com.sun.jmx.snmp.agent.SnmpMibTable public Object getEntry(SnmpOid oid) throws SnmpStatusException { final boolean dbg = log.isDebugOn(); if (dbg) log.debug("getEntry", "oid [" + oid + "]"); if (oid == null || oid.getLength() != 1) { if (dbg) log.debug("getEntry", "Invalid oid [" + oid + "]"); throw new SnmpStatusException(SnmpStatusException.noSuchInstance); } // Get the request contextual cache (userData). // final Map<Object, Object> m = JvmContextFactory.getUserData(); // We're going to use this name to store/retrieve the entry in // the request contextual cache. // // Revisit: Probably better programming to put all these strings // in some interface. // final String entryTag = ((m==null)?null: ("JvmRTClassPathTable.entry." + oid.toString())); // If the entry is in the cache, simply return it. // if (m != null) { final Object entry = m.get(entryTag); if (entry != null) { if (dbg) log.debug("getEntry", "Entry is already in the cache"); return entry; } else if (dbg) log.debug("getEntry", "Entry is not in the cache"); } // The entry was not in the cache, make a new one. // // Get the data hanler. // SnmpTableHandler handler = getHandler(m); // handler should never be null. // if (handler == null) throw new SnmpStatusException(SnmpStatusException.noSuchInstance); // Get the data associated with our entry. // final Object data = handler.getData(oid); // data may be null if the OID we were given is not valid. // if (data == null) throw new SnmpStatusException(SnmpStatusException.noSuchInstance); // make the new entry (transient object that will be kept only // for the duration of the request. // if (dbg) log.debug("getEntry","data is a: " + data.getClass().getName()); final Object entry = new JvmRTClassPathEntryImpl((String) data, (int) oid.getOidArc(0)); // Put the entry in the cache in case we need it later while processing // the request. // if (m != null && entry != null) { m.put(entryTag,entry); } return entry; }
Get the SnmpTableHandler that holds the jvmThreadInstanceTable data. First look it up in the request contextual cache, and if it is not found, obtain it from the weak cache.
The request contextual cache will be released at the end of the current requests, and is used only to process this request.
The weak cache is shared by all requests, and is only recomputed when it is found to be obsolete.
Note that the data put in the request contextual cache is never considered to be obsolete, in order to preserve data coherency.
/** * Get the SnmpTableHandler that holds the jvmThreadInstanceTable data. * First look it up in the request contextual cache, and if it is * not found, obtain it from the weak cache. * <br>The request contextual cache will be released at the end of the * current requests, and is used only to process this request. * <br>The weak cache is shared by all requests, and is only * recomputed when it is found to be obsolete. * <br>Note that the data put in the request contextual cache is * never considered to be obsolete, in order to preserve data * coherency. **/
protected SnmpTableHandler getHandler(Object userData) { final Map<Object, Object> m; if (userData instanceof Map) m=Util.cast(userData); else m=null; // Look in the contextual cache. if (m != null) { final SnmpTableHandler handler = (SnmpTableHandler)m.get("JvmRTClassPathTable.handler"); if (handler != null) return handler; } // No handler in contextual cache, make a new one. final SnmpTableHandler handler = cache.getTableHandler(); if (m != null && handler != null ) m.put("JvmRTClassPathTable.handler",handler); return handler; } static final MibLogger log = new MibLogger(JvmRTClassPathTableMetaImpl.class); }