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| SolarMetric Kodo JDO 3.4.1 generated on May 30 2006
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## kodo.datacache
Class AbstractQueryCache

    java.lang.Object
      |
      +--serp.util.AbstractEventManager
            |
            +--kodo.datacache.AbstractQueryCache

All Implemented Interfaces:
  com.solarmetric.util.Closeable, Configurable, QueryCache

Direct Known Subclasses:
  GemFireQueryCache, QueryCacheImpl, TangosolQueryCache

public abstract class AbstractQueryCache
extends serp.util.AbstractEventManager
implements QueryCache, Configurable

Abstract `QueryCache` implementation that provides various statistics, logging, and timeout functionality common across cache implementations.

Field Summary
`protected JDOConfiguration` | `conf` The configuration set by the system.
`protected Log` | `log` The log to use.

Constructor Summary
`AbstractQueryCache()`

Method Summary
`void` | `addExpirationListener(ExpirationListener listen)` Add a new expiration event listener to this cache.
`void` | `afterCommit(RemoteCommitEvent event)` This method is part of the `RemoteCommitListener` interface.
`void` | `classesChanged(Collection classes)` Tells the cache that all the classes in the `classes` set have been changed.
`void` | `clear()` Remove all data from this cache.
`protected abstract void` | `clearInternal()` Clear the cache.
`void` | `close()` Free the resources used by this cache.
`protected void` | `closeWithoutClear()`
`void` | `endConfiguration()` Invoked upon completion of bean property configuration for this object.
`protected void` | `fireEvent(Object event, Object listener)`
`QueryResult` | `get(QueryKey key)` Return a list of oids for the given query key.
`double` | `getHitRate()` Returns the percentage of hits.
`int` | `getHits()` Returns the number of cache hits for invocations of the `get(kodo.datacache.QueryKey)` method.
`protected abstract QueryResult` | `getInternal(QueryKey qk)` Return the list for the given key.
`int` | `getMisses()` Returns the number of cache misses for invocations of the `get(kodo.datacache.QueryKey)` method.
`Collection` | `getStatistics()` Get statistics exported by this object.
`String` | `getStatisticsString()` Returns a localized string containing the number of hits, the number of misses, and the hit ratio (`hits / (hits+misses)`).
`boolean` | `isClosed()`
`protected void` | `keyRemoved(Object key, boolean expired)` Invoke when a key is removed from this cache.
`protected abstract Collection` | `keySet()` Return a threadsafe view of the keys in this cache.
`protected Collection` | `newListenerCollection()` Individual query results will be registered as expiration listeners.
`boolean` | `pin(QueryKey key)` Pin the value stored under `qk` into the cache.
`protected abstract boolean` | `pinInternal(QueryKey qk)` Pin an object to the cache.
`QueryResult` | `put(QueryKey qk, QueryResult oids)` Set the list of OIDs for the given query key.
`protected abstract QueryResult` | `putInternal(QueryKey qk, QueryResult oids)` Add the given result to the cache, returning the old result under the given key.
`QueryResult` | `remove(QueryKey key)` Remove the value stored under the given query key.
`protected void` | `removeAllInternal(Collection qks)` Remove all results under the given keys from the cache.
`boolean` | `removeExpirationListener(ExpirationListener listen)` Remove an expiration event listener from this cache.
`protected abstract QueryResult` | `removeInternal(QueryKey qk)` Remove the result under the given key from the cache.
`void` | `resetStatistics()` Reset the caching statistics.
`void` | `setConfiguration(Configuration conf)` Invoked prior to setting bean properties.
`void` | `startConfiguration()` Invoked before bean property configuration is begun on this object.
`boolean` | `unpin(QueryKey key)` Unpin the value stored under `key` into the cache.
`protected abstract boolean` | `unpinInternal(QueryKey qk)` Unpin an object from the cache.

Methods inherited from class serp.util.AbstractEventManager
`fireEvent, getListeners, hasListener, hasListeners, registerListener, removeListener`

Methods inherited from class java.lang.Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

Field Detail

### conf

    protected JDOConfiguration conf

  The configuration set by the system.

### log

    protected Log log

  The log to use.

Constructor Detail

### AbstractQueryCache

    public AbstractQueryCache()

Method Detail

### classesChanged

    public void classesChanged(Collection classes)

  Description copied from interface: `QueryCache`

  Tells the cache that all the classes in the `classes` set have been changed. This could mean that items have been updated, deleted, or added. This limits the `QueryCache` to only be able to invalidate cached queries -- because the cache is not notified of actual changes, it cannot recompute query results.

  After this method is invoked, all cached results that correspond to queries that use one of the classes in `classes` will be dropped.

  Specified by:
    `classesChanged` in interface `QueryCache`
  Following copied from interface: `kodo.datacache.QueryCache`
  Parameters:
    `classes` - a set of `Class` objects that correspond to instances that have changed

### get

    public QueryResult get(QueryKey key)

  Description copied from interface: `QueryCache`

  Return a list of oids for the given query key. This is an unmodifiable list.

  Specified by:
    `get` in interface `QueryCache`
  Following copied from interface: `kodo.datacache.QueryCache`
  Returns:
    The query results matching the given key, or null if none

### put

    public QueryResult put(QueryKey qk,
                           QueryResult oids)

  Description copied from interface: `QueryCache`

  Set the list of OIDs for the given query key. A reference to the given list will be stored in the query cache, so the list should not be modified after invoking this method.

  Specified by:
    `put` in interface `QueryCache`
  Following copied from interface: `kodo.datacache.QueryCache`
  Returns:
    The previously cached value, or `null` if the key was not previously cached. See `Map.put(java.lang.Object, java.lang.Object)` for more information.

### remove

    public QueryResult remove(QueryKey key)

  Description copied from interface: `QueryCache`

  Remove the value stored under the given query key.

  This method is typically not invoked directly from outside the `QueryCache` class. Instead, the cache should be updated by invoking `#notifyChangedClasses`, which will result in all queries that may be invalid being dropped.

  Specified by:
    `remove` in interface `QueryCache`
  Following copied from interface: `kodo.datacache.QueryCache`
  Returns:
    The previously cached value, or `null` if the key was not previously cached. See `Map.remove(java.lang.Object)` for more information.

### pin

    public boolean pin(QueryKey key)

  Description copied from interface: `QueryCache`
  Pin the value stored under `qk` into the cache. This method guarantees that `qk`'s value will not be expired if the cache exceeds its capacity. It causes this data to be ignored when determining whether or not the cache is full, effectively increasing the total amount of data stored in the cache. This method does not affect the behavior of `QueryCache.remove(kodo.datacache.QueryKey)` or `#notifyChangedClasses`.
  Specified by:
    `pin` in interface `QueryCache`
  Following copied from interface: `kodo.datacache.QueryCache`
  Returns:
    `true` if `key`'s value was pinned into the cache; `false` if the key is not in the cache.

### unpin

    public boolean unpin(QueryKey key)

  Description copied from interface: `QueryCache`
  Unpin the value stored under `key` into the cache. This method reverses a previous invocation of `QueryCache.pin(kodo.datacache.QueryKey)`. This method does not remove anything from the cache; it merely makes `key`'s value a candidate for flushing from the cache.
  Specified by:
    `unpin` in interface `QueryCache`
  Following copied from interface: `kodo.datacache.QueryCache`
  Returns:
    `true` if `key`'s value was unpinned from the cache; `false` if the key is not in the cache.

### clear

    public void clear()

  Description copied from interface: `QueryCache`

  Remove all data from this cache.

  Specified by:
    `clear` in interface `QueryCache`

### close

    public void close()

  Description copied from interface: `QueryCache`
  Free the resources used by this cache.
  Specified by:
    `close` in interface `QueryCache`

### closeWithoutClear

    protected void closeWithoutClear()

### isClosed

    public boolean isClosed()

### addExpirationListener

    public void addExpirationListener(ExpirationListener listen)

  Description copied from interface: `QueryCache`
  Add a new expiration event listener to this cache.
  Specified by:
    `addExpirationListener` in interface `QueryCache`

### removeExpirationListener

    public boolean removeExpirationListener(ExpirationListener listen)

  Description copied from interface: `QueryCache`
  Remove an expiration event listener from this cache.
  Specified by:
    `removeExpirationListener` in interface `QueryCache`

### afterCommit

    public void afterCommit(RemoteCommitEvent event)

  This method is part of the `RemoteCommitListener` interface. If your cache subclass relies on Kodo for clustering support, make it implement `RemoteCommitListener`. This method will take care of invalidating entries from remote commits, by delegating to `classesChanged(java.util.Collection)`.

### keyRemoved

    protected void keyRemoved(Object key,
                              boolean expired)

  Invoke when a key is removed from this cache. Propagates the expiration event on to all expiration listeners registered with this class.

### keySet

    protected abstract Collection keySet()

  Return a threadsafe view of the keys in this cache. This collection must be iteratable without risk of concurrent modification exceptions. It does not have to implement contains() efficiently or use set semantics.

### getInternal

    protected abstract QueryResult getInternal(QueryKey qk)

  Return the list for the given key.

### putInternal

    protected abstract QueryResult putInternal(QueryKey qk,
                                               QueryResult oids)

  Add the given result to the cache, returning the old result under the given key.

### removeInternal

    protected abstract QueryResult removeInternal(QueryKey qk)

  Remove the result under the given key from the cache.

### removeAllInternal

    protected void removeAllInternal(Collection qks)

  Remove all results under the given keys from the cache.

### clearInternal

    protected abstract void clearInternal()

  Clear the cache.

### pinInternal

    protected abstract boolean pinInternal(QueryKey qk)

  Pin an object to the cache.

### unpinInternal

    protected abstract boolean unpinInternal(QueryKey qk)

  Unpin an object from the cache.

### getHits

    public int getHits()

  Returns the number of cache hits for invocations of the `get(kodo.datacache.QueryKey)` method.

### getMisses

    public int getMisses()

  Returns the number of cache misses for invocations of the `get(kodo.datacache.QueryKey)` method.

### getHitRate

    public double getHitRate()

  Returns the percentage of hits.

### getStatisticsString

    public String getStatisticsString()

  Returns a localized string containing the number of hits, the number of misses, and the hit ratio (`hits / (hits+misses)`).

### getStatistics

    public Collection getStatistics()

  Get statistics exported by this object.

### resetStatistics

    public void resetStatistics()

  Reset the caching statistics.

### setConfiguration

    public void setConfiguration(Configuration conf)

  Description copied from interface: `Configurable`
  Invoked prior to setting bean properties.
  Specified by:
    `setConfiguration` in interface `Configurable`

### startConfiguration

    public void startConfiguration()

  Description copied from interface: `Configurable`
  Invoked before bean property configuration is begun on this object.
  Specified by:
    `startConfiguration` in interface `Configurable`

### endConfiguration

    public void endConfiguration()

  Description copied from interface: `Configurable`
  Invoked upon completion of bean property configuration for this object.
  Specified by:
    `endConfiguration` in interface `Configurable`

### fireEvent

    protected void fireEvent(Object event,
                             Object listener)

  Overrides:
    `fireEvent` in class `serp.util.AbstractEventManager`

### newListenerCollection

    protected Collection newListenerCollection()

  Individual query results will be registered as expiration listeners. We want such query results to be gc'ed once the only reference is held by the list of expiration listeners.
  Overrides:
    `newListenerCollection` in class `serp.util.AbstractEventManager`

Overview | Package | Class | Tree | Deprecated | Index | Help
| SolarMetric Kodo JDO 3.4.1 generated on May 30 2006
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