/* * Copyright (c) 2003, 2006, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * 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). * * 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, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */package sun.management.snmp.util; import com.sun.jmx.snmp.SnmpOid;import com.sun.jmx.mbeanserver.Util; import java.io.Serializable; import java.util.Comparator;import java.util.Arrays;import java.util.Map;import java.util.TreeMap;import java.util.List;import java.util.Iterator; import java.lang.ref.WeakReference; /** * This abstract class implements a weak cache that holds table data, for * a table whose data is obtained from a list where a name can be obtained * for each item in the list. * <p>This object maintains a map between an entry name and its associated * SnmpOid index, so that a given entry is always associated to the same * index.</p> * <p><b>NOTE: This class is not synchronized, subclasses must implement * the appropriate synchronization whwn needed.</b></p> **/public abstract class SnmpNamedListTableCache extends SnmpListTableCache { /** * This map associate an entry name with the SnmpOid index that's * been allocated for it. **/ protected TreeMap names = new TreeMap(); /** * The last allocate index. **/ protected long last = 0; /** * true if the index has wrapped. **/ boolean wrapped = false; /** * Returns the key to use as name for the given <var>item</var>. * <br>This method is called by {@link #getIndex(Object,List,int,Object)}. * The given <var>item</var> is expected to be always associated with * the same name. * @param context The context passed to * {@link #updateCachedDatas(Object,List)}. * @param rawDatas Raw table datas passed to * {@link #updateCachedDatas(Object,List)}. * @param rank Rank of the given <var>item</var> in the * <var>rawDatas</var> list iterator. * @param item The raw data object for which a key name must be determined. **/ protected abstract String getKey(Object context, List rawDatas, int rank, Object item); /** * Find a new index for the entry corresponding to the * given <var>item</var>. * <br>This method is called by {@link #getIndex(Object,List,int,Object)} * when a new index needs to be allocated for an <var>item</var>. The * index returned must not be already in used. * @param context The context passed to * {@link #updateCachedDatas(Object,List)}. * @param rawDatas Raw table datas passed to * {@link #updateCachedDatas(Object,List)}. * @param rank Rank of the given <var>item</var> in the * <var>rawDatas</var> list iterator. * @param item The raw data object for which an index must be determined. **/ protected SnmpOid makeIndex(Object context, List rawDatas, int rank, Object item) { // check we are in the limits of an unsigned32. if (++last > 0x00000000FFFFFFFFL) { // we just wrapped. log.debug("makeIndex", "Index wrapping..."); last = 0; wrapped=true; } // If we never wrapped, we can safely return last as new index. if (!wrapped) return new SnmpOid(last); // We wrapped. We must look for an unused index. for (int i=1;i < 0x00000000FFFFFFFFL;i++) { if (++last > 0x00000000FFFFFFFFL) last = 1; final SnmpOid testOid = new SnmpOid(last); // Was this index already in use? if (names == null) return testOid; if (names.containsValue(testOid)) continue; // Have we just used it in a previous iteration? if (context == null) return testOid; if (((Map)context).containsValue(testOid)) continue; // Ok, not in use. return testOid; } // all indexes are in use! we're stuck. // // throw new IndexOutOfBoundsException("No index available."); // better to return null and log an error. return null; } /** * Call {@link #getKey(Object,List,int,Object)} in order to get * the item name. Then check whether an index was already allocated * for the entry by that name. If yes return it. Otherwise, call * {@link #makeIndex(Object,List,int,Object)} to compute a new * index for that entry. * Finally store the association between * the name and index in the context TreeMap. * @param context The context passed to * {@link #updateCachedDatas(Object,List)}. * It is expected to * be an instance of {@link TreeMap}. * @param rawDatas Raw table datas passed to * {@link #updateCachedDatas(Object,List)}. * @param rank Rank of the given <var>item</var> in the * <var>rawDatas</var> list iterator. * @param item The raw data object for which an index must be determined. **/ protected SnmpOid getIndex(Object context, List rawDatas, int rank, Object item) { final String key = getKey(context,rawDatas,rank,item); final Object index = (names==null||key==null)?null:names.get(key); final SnmpOid result = ((index != null)?((SnmpOid)index):makeIndex(context,rawDatas, rank,item)); if ((context != null) && (key != null) && (result != null)) { Map<Object, Object> map = Util.cast(context); map.put(key,result); } log.debug("getIndex","key="+key+", index="+result); return result; } /** * Allocate a new {@link TreeMap} to serve as context, then * call {@link SnmpListTableCache#updateCachedDatas(Object,List)}, and * finally replace the {@link #names} TreeMap by the new allocated * TreeMap. * @param rawDatas The table datas from which the cached data will be * computed. **/ protected SnmpCachedData updateCachedDatas(Object context, List rawDatas) { TreeMap ctxt = new TreeMap(); final SnmpCachedData result = super.updateCachedDatas(context,rawDatas); names = ctxt; return result; } /** * Load a list of raw data from which to build the cached data. * This method is called when nothing is found in the request * contextual cache. * @param userData The request contextual cache allocated by * the {@link JvmContextFactory}. * **/ protected abstract List loadRawDatas(Map userData); /** *The name under which the raw data is to be found/put in * the request contextual cache. **/ protected abstract String getRawDatasKey(); /** * Get a list of raw data from which to build the cached data. * Obtains a list of raw data by first looking it up in the * request contextual cache <var>userData</var> under the given * <var>key</var>. If nothing is found in the cache, calls * {@link #loadRawDatas(Map)} to obtain a new rawData list, * and cache the result in <var>userData</var> under <var>key</var>. * @param userData The request contextual cache allocated by * the {@link JvmContextFactory}. * @param key The name under which the raw data is to be found/put in * the request contextual cache. * **/ protected List getRawDatas(Map<Object, Object> userData, String key) { List rawDatas = null; // Look for memory manager list in request contextual cache. if (userData != null) rawDatas = (List) userData.get(key); if (rawDatas == null) { // No list in contextual cache, get it from API rawDatas = loadRawDatas(userData); // Put list in cache... if (rawDatas != null && userData != null) userData.put(key, rawDatas); } return rawDatas; } /** * Update cahed datas. * Obtains a {@link List} of raw datas by calling * {@link #getRawDatas(Map,String) getRawDatas((Map)context,getRawDatasKey())}.<br> * Then allocate a new {@link TreeMap} to serve as temporary map between * names and indexes, and call {@link #updateCachedDatas(Object,List)} * with that temporary map as context.<br> * Finally replaces the {@link #names} TreeMap by the temporary * TreeMap. * @param context The request contextual cache allocated by the * {@link JvmContextFactory}. **/ protected SnmpCachedData updateCachedDatas(Object context) { final Map<Object, Object> userData = (context instanceof Map)?Util.<Map<Object, Object>>cast(context):null; // Look for memory manager list in request contextual cache. final List rawDatas = getRawDatas(userData,getRawDatasKey()); log.debug("updateCachedDatas","rawDatas.size()=" + ((rawDatas==null)?"<no data>":""+rawDatas.size())); TreeMap ctxt = new TreeMap(); final SnmpCachedData result = super.updateCachedDatas(ctxt,rawDatas); names = ctxt; return result; } static final MibLogger log = new MibLogger(SnmpNamedListTableCache.class);}
/*
* Copyright (c) 2003, 2006, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* 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).
*
* 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,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package sun.management.snmp.util;
import com.sun.jmx.snmp.SnmpOid;
import com.sun.jmx.mbeanserver.Util;
import java.io.Serializable;
import java.util.Comparator;
import java.util.Arrays;
import java.util.Map;
import java.util.TreeMap;
import java.util.List;
import java.util.Iterator;
import java.lang.ref.WeakReference;
/**
* This abstract class implements a weak cache that holds table data, for
* a table whose data is obtained from a list where a name can be obtained
* for each item in the list.
* <p>This object maintains a map between an entry name and its associated
* SnmpOid index, so that a given entry is always associated to the same
* index.</p>
* <p><b>NOTE: This class is not synchronized, subclasses must implement
* the appropriate synchronization whwn needed.</b></p>
**/
public abstract class SnmpNamedListTableCache extends SnmpListTableCache {
/**
* This map associate an entry name with the SnmpOid index that's
* been allocated for it.
**/
protected TreeMap names = new TreeMap();
/**
* The last allocate index.
**/
protected long last = 0;
/**
* true if the index has wrapped.
**/
boolean wrapped = false;
/**
* Returns the key to use as name for the given <var>item</var>.
* <br>This method is called by {@link #getIndex(Object,List,int,Object)}.
* The given <var>item</var> is expected to be always associated with
* the same name.
* @param context The context passed to
* {@link #updateCachedDatas(Object,List)}.
* @param rawDatas Raw table datas passed to
* {@link #updateCachedDatas(Object,List)}.
* @param rank Rank of the given <var>item</var> in the
* <var>rawDatas</var> list iterator.
* @param item The raw data object for which a key name must be determined.
**/
protected abstract String getKey(Object context, List rawDatas,
int rank, Object item);
/**
* Find a new index for the entry corresponding to the
* given <var>item</var>.
* <br>This method is called by {@link #getIndex(Object,List,int,Object)}
* when a new index needs to be allocated for an <var>item</var>. The
* index returned must not be already in used.
* @param context The context passed to
* {@link #updateCachedDatas(Object,List)}.
* @param rawDatas Raw table datas passed to
* {@link #updateCachedDatas(Object,List)}.
* @param rank Rank of the given <var>item</var> in the
* <var>rawDatas</var> list iterator.
* @param item The raw data object for which an index must be determined.
**/
protected SnmpOid makeIndex(Object context, List rawDatas,
int rank, Object item) {
// check we are in the limits of an unsigned32.
if (++last > 0x00000000FFFFFFFFL) {
// we just wrapped.
log.debug("makeIndex", "Index wrapping...");
last = 0;
wrapped=true;
}
// If we never wrapped, we can safely return last as new index.
if (!wrapped) return new SnmpOid(last);
// We wrapped. We must look for an unused index.
for (int i=1;i < 0x00000000FFFFFFFFL;i++) {
if (++last > 0x00000000FFFFFFFFL) last = 1;
final SnmpOid testOid = new SnmpOid(last);
// Was this index already in use?
if (names == null) return testOid;
if (names.containsValue(testOid)) continue;
// Have we just used it in a previous iteration?
if (context == null) return testOid;
if (((Map)context).containsValue(testOid)) continue;
// Ok, not in use.
return testOid;
}
// all indexes are in use! we're stuck.
// // throw new IndexOutOfBoundsException("No index available.");
// better to return null and log an error.
return null;
}
/**
* Call {@link #getKey(Object,List,int,Object)} in order to get
* the item name. Then check whether an index was already allocated
* for the entry by that name. If yes return it. Otherwise, call
* {@link #makeIndex(Object,List,int,Object)} to compute a new
* index for that entry.
* Finally store the association between
* the name and index in the context TreeMap.
* @param context The context passed to
* {@link #updateCachedDatas(Object,List)}.
* It is expected to
* be an instance of {@link TreeMap}.
* @param rawDatas Raw table datas passed to
* {@link #updateCachedDatas(Object,List)}.
* @param rank Rank of the given <var>item</var> in the
* <var>rawDatas</var> list iterator.
* @param item The raw data object for which an index must be determined.
**/
protected SnmpOid getIndex(Object context, List rawDatas,
int rank, Object item) {
final String key = getKey(context,rawDatas,rank,item);
final Object index = (names==null||key==null)?null:names.get(key);
final SnmpOid result =
((index != null)?((SnmpOid)index):makeIndex(context,rawDatas,
rank,item));
if ((context != null) && (key != null) && (result != null)) {
Map<Object, Object> map = Util.cast(context);
map.put(key,result);
}
log.debug("getIndex","key="+key+", index="+result);
return result;
}
/**
* Allocate a new {@link TreeMap} to serve as context, then
* call {@link SnmpListTableCache#updateCachedDatas(Object,List)}, and
* finally replace the {@link #names} TreeMap by the new allocated
* TreeMap.
* @param rawDatas The table datas from which the cached data will be
* computed.
**/
protected SnmpCachedData updateCachedDatas(Object context, List rawDatas) {
TreeMap ctxt = new TreeMap();
final SnmpCachedData result =
super.updateCachedDatas(context,rawDatas);
names = ctxt;
return result;
}
/**
* Load a list of raw data from which to build the cached data.
* This method is called when nothing is found in the request
* contextual cache.
* @param userData The request contextual cache allocated by
* the {@link JvmContextFactory}.
*
**/
protected abstract List loadRawDatas(Map userData);
/**
*The name under which the raw data is to be found/put in
* the request contextual cache.
**/
protected abstract String getRawDatasKey();
/**
* Get a list of raw data from which to build the cached data.
* Obtains a list of raw data by first looking it up in the
* request contextual cache <var>userData</var> under the given
* <var>key</var>. If nothing is found in the cache, calls
* {@link #loadRawDatas(Map)} to obtain a new rawData list,
* and cache the result in <var>userData</var> under <var>key</var>.
* @param userData The request contextual cache allocated by
* the {@link JvmContextFactory}.
* @param key The name under which the raw data is to be found/put in
* the request contextual cache.
*
**/
protected List getRawDatas(Map<Object, Object> userData, String key) {
List rawDatas = null;
// Look for memory manager list in request contextual cache.
if (userData != null)
rawDatas = (List) userData.get(key);
if (rawDatas == null) {
// No list in contextual cache, get it from API
rawDatas = loadRawDatas(userData);
// Put list in cache...
if (rawDatas != null && userData != null)
userData.put(key, rawDatas);
}
return rawDatas;
}
/**
* Update cahed datas.
* Obtains a {@link List} of raw datas by calling
* {@link #getRawDatas(Map,String) getRawDatas((Map)context,getRawDatasKey())}.<br>
* Then allocate a new {@link TreeMap} to serve as temporary map between
* names and indexes, and call {@link #updateCachedDatas(Object,List)}
* with that temporary map as context.<br>
* Finally replaces the {@link #names} TreeMap by the temporary
* TreeMap.
* @param context The request contextual cache allocated by the
* {@link JvmContextFactory}.
**/
protected SnmpCachedData updateCachedDatas(Object context) {
final Map<Object, Object> userData =
(context instanceof Map)?Util.<Map<Object, Object>>cast(context):null;
// Look for memory manager list in request contextual cache.
final List rawDatas = getRawDatas(userData,getRawDatasKey());
log.debug("updateCachedDatas","rawDatas.size()=" +
((rawDatas==null)?"<no data>":""+rawDatas.size()));
TreeMap ctxt = new TreeMap();
final SnmpCachedData result =
super.updateCachedDatas(ctxt,rawDatas);
names = ctxt;
return result;
}
static final MibLogger log = new MibLogger(SnmpNamedListTableCache.class);
}