releases/latest/javadoc/org/apache/geode/cache/package-summary.html - geode-site - Git at Google

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 <h1 title="Package" class="title">Package&nbsp;org.apache.geode.cache</h1>
 <div class="docSummary">
 <div class="block">Provides an implementation of distributed object caching that
 can leverage GemFire's distribution capabilities.</div>
 </div>
 <p>See:&nbsp;<a href="#package.description">Description</a></p>
 </div>
 <div class="contentContainer">
 <ul class="blockList">
 <li class="blockList">
 <table class="typeSummary" border="0" cellpadding="3" cellspacing="0" summary="Interface Summary table, listing interfaces, and an explanation">
 <caption><span>Interface Summary</span><span class="tabEnd">&nbsp;</span></caption>
 <tr>
 <th class="colFirst" scope="col">Interface</th>
 <th class="colLast" scope="col">Description</th>
 </tr>
 <tbody>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/AttributesMutator.html" title="interface in org.apache.geode.cache">AttributesMutator</a>&lt;K,V&gt;</td>
 <td class="colLast">
 <div class="block">Supports modification of certain region attributes after the region has been created.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/Cache.html" title="interface in org.apache.geode.cache">Cache</a></td>
 <td class="colLast">
 <div class="block">Caches are obtained from the <a href="../../../../org/apache/geode/cache/CacheFactory.html#create--"><code>CacheFactory.create()</code></a> method.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/CacheCallback.html" title="interface in org.apache.geode.cache">CacheCallback</a></td>
 <td class="colLast">
 <div class="block">User-defined objects that can be plugged into caching to receive callback notifications.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/CacheEvent.html" title="interface in org.apache.geode.cache">CacheEvent</a>&lt;K,V&gt;</td>
 <td class="colLast">
 <div class="block">A region- or entry-related event affecting the cache.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/CacheListener.html" title="interface in org.apache.geode.cache">CacheListener</a>&lt;K,V&gt;</td>
 <td class="colLast">
 <div class="block">
  A listener to handle region or entry related events.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/CacheLoader.html" title="interface in org.apache.geode.cache">CacheLoader</a>&lt;K,V&gt;</td>
 <td class="colLast">
 <div class="block">Allows data from outside of the VM to be placed into a region.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/CacheStatistics.html" title="interface in org.apache.geode.cache">CacheStatistics</a></td>
 <td class="colLast">
 <div class="block">Defines common statistics information for both region and entries.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/CacheTransactionManager.html" title="interface in org.apache.geode.cache">CacheTransactionManager</a></td>
 <td class="colLast">
 <div class="block">
  The CacheTransactionManager interface allows applications to manage transactions on a per
  <a href="../../../../org/apache/geode/cache/Cache.html" title="interface in org.apache.geode.cache"><code>Cache</code></a> basis.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/CacheWriter.html" title="interface in org.apache.geode.cache">CacheWriter</a>&lt;K,V&gt;</td>
 <td class="colLast">
 <div class="block">A user-defined object defined in the <a href="../../../../org/apache/geode/cache/RegionAttributes.html" title="interface in org.apache.geode.cache"><code>RegionAttributes</code></a> that is called synchronously before
  a region or entry in the cache is modified.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/ClientSession.html" title="interface in org.apache.geode.cache">ClientSession</a></td>
 <td class="colLast">
 <div class="block">Class <code>ClientSession</code> represents a client connection on the server.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/CustomExpiry.html" title="interface in org.apache.geode.cache">CustomExpiry</a>&lt;K,V&gt;</td>
 <td class="colLast">
 <div class="block">This is the contract that a <code>custom-expiry</code> element must honor.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/Declarable.html" title="interface in org.apache.geode.cache">Declarable</a></td>
 <td class="colLast">
 <div class="block">An object that can be described in a declarative caching XML file.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/DiskStore.html" title="interface in org.apache.geode.cache">DiskStore</a></td>
 <td class="colLast">
 <div class="block">Provides disk storage for one or more regions.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/DiskStoreFactory.html" title="interface in org.apache.geode.cache">DiskStoreFactory</a></td>
 <td class="colLast">
 <div class="block">Factory for creating instances of <a href="../../../../org/apache/geode/cache/DiskStore.html" title="interface in org.apache.geode.cache"><code>DiskStore</code></a>.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/DiskWriteAttributes.html" title="interface in org.apache.geode.cache">DiskWriteAttributes</a></td>
 <td class="colLast">Deprecated
 <div class="block"><span class="deprecationComment">as of 6.5 use <a href="../../../../org/apache/geode/cache/DiskStore.html" title="interface in org.apache.geode.cache"><code>DiskStore</code></a> instead</span></div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/DynamicRegionListener.html" title="interface in org.apache.geode.cache">DynamicRegionListener</a></td>
 <td class="colLast">
 <div class="block"><code>DynamicRegionListener</code> is an interface that can be implemented to handle dynamic
  region-related events.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/EntryEvent.html" title="interface in org.apache.geode.cache">EntryEvent</a>&lt;K,V&gt;</td>
 <td class="colLast">
 <div class="block">Contains information about an event affecting an entry, including its identity and the the
  circumstances of the event.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/EntryOperation.html" title="interface in org.apache.geode.cache">EntryOperation</a>&lt;K,V&gt;</td>
 <td class="colLast">
 <div class="block">Gemfire Context passed to <code>PartitionResolver</code> to compute the data location</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/EvictionAttributesMutator.html" title="interface in org.apache.geode.cache">EvictionAttributesMutator</a></td>
 <td class="colLast">
 <div class="block">The EvictionAttributesMutator allows changes to be made to a
  <a href="../../../../org/apache/geode/cache/EvictionAttributes.html" title="class in org.apache.geode.cache"><code>EvictionAttributes</code></a>.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/FixedPartitionResolver.html" title="interface in org.apache.geode.cache">FixedPartitionResolver</a>&lt;K,V&gt;</td>
 <td class="colLast">
 <div class="block">Implementers of interface <code>FixedPartitionResolver</code> helps to achieve explicit mapping
  of a "user defined" partition to a data member node.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/GemFireCache.html" title="interface in org.apache.geode.cache">GemFireCache</a></td>
 <td class="colLast">
 <div class="block">GemFireCache represents the singleton cache that must be created in order to use GemFire in a
  Java virtual machine.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/InterestRegistrationEvent.html" title="interface in org.apache.geode.cache">InterestRegistrationEvent</a></td>
 <td class="colLast">
 <div class="block">Interface <code>InterestRegistrationEvent</code> encapsulated interest event information like
  region and keys of interest.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/InterestRegistrationListener.html" title="interface in org.apache.geode.cache">InterestRegistrationListener</a></td>
 <td class="colLast">
 <div class="block">Interface <code>InterestRegisterationListener</code> provides the ability for applications to be
  notified of interest registration and unregistration events.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/LoaderHelper.html" title="interface in org.apache.geode.cache">LoaderHelper</a>&lt;K,V&gt;</td>
 <td class="colLast">
 <div class="block">Provides a set of APIs to help the implementation of the <code>CacheLoader</code> load method.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/PartitionAttributes.html" title="interface in org.apache.geode.cache">PartitionAttributes</a>&lt;K,V&gt;</td>
 <td class="colLast">
 <div class="block">Attributes that define the partitioned character of a Partitioned Region.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/PartitionResolver.html" title="interface in org.apache.geode.cache">PartitionResolver</a>&lt;K,V&gt;</td>
 <td class="colLast">
 <div class="block">Implementers of interface <code>PartitionResolver</code> enable custom standard partitioning on
  the <code>PartitionedRegion</code>.<br>
  See <code>FixedPartitionResolver</code> to enable custom fixed partitioning.<br></div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/Region.html" title="interface in org.apache.geode.cache">Region</a>&lt;K,V&gt;</td>
 <td class="colLast">
 <div class="block">Manages subregions and cached data.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/Region.Entry.html" title="interface in org.apache.geode.cache">Region.Entry</a>&lt;K,V&gt;</td>
 <td class="colLast">
 <div class="block">A key-value pair containing the cached data in a region.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/RegionAttributes.html" title="interface in org.apache.geode.cache">RegionAttributes</a>&lt;K,V&gt;</td>
 <td class="colLast">
 <div class="block">Defines attributes for configuring a region.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/RegionEvent.html" title="interface in org.apache.geode.cache">RegionEvent</a>&lt;K,V&gt;</td>
 <td class="colLast">
 <div class="block">Contains information about an event affecting a region, including its identity and the
  circumstances of the event.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/RegionMembershipListener.html" title="interface in org.apache.geode.cache">RegionMembershipListener</a>&lt;K,V&gt;</td>
 <td class="colLast">
 <div class="block">A listener that can be implemented to handle region membership events.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/RegionRoleListener.html" title="interface in org.apache.geode.cache">RegionRoleListener</a>&lt;K,V&gt;</td>
 <td class="colLast">Deprecated
 <div class="block"><span class="deprecationComment">this feature is scheduled to be removed</span></div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/RegionService.html" title="interface in org.apache.geode.cache">RegionService</a></td>
 <td class="colLast">
 <div class="block">A RegionService provides access to existing <a href="../../../../org/apache/geode/cache/Region.html" title="interface in org.apache.geode.cache"><code>regions</code></a> that exist in a
  <a href="../../../../org/apache/geode/cache/GemFireCache.html" title="interface in org.apache.geode.cache"><code>GemFire cache</code></a>.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/RoleEvent.html" title="interface in org.apache.geode.cache">RoleEvent</a>&lt;K,V&gt;</td>
 <td class="colLast">Deprecated
 <div class="block"><span class="deprecationComment">this feature is scheduled to be removed</span></div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/SerializedCacheValue.html" title="interface in org.apache.geode.cache">SerializedCacheValue</a>&lt;V&gt;</td>
 <td class="colLast">
 <div class="block">Class <code>SerializedCacheValue</code> represents a serialized cache value.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/TransactionEvent.html" title="interface in org.apache.geode.cache">TransactionEvent</a></td>
 <td class="colLast">
 <div class="block">
  An event that describes the culmination of an entire transaction.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/TransactionId.html" title="interface in org.apache.geode.cache">TransactionId</a></td>
 <td class="colLast">
 <div class="block">The TransactionId interface is a "marker" interface that represents a unique GemFire transaction.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/TransactionListener.html" title="interface in org.apache.geode.cache">TransactionListener</a></td>
 <td class="colLast">
 <div class="block">
  A listener that can be implemented to handle transaction related events.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/TransactionWriter.html" title="interface in org.apache.geode.cache">TransactionWriter</a></td>
 <td class="colLast">
 <div class="block">A callback that is allowed to veto a transaction.</div>
 </td>
 </tr>
 </tbody>
 </table>
 </li>
 <li class="blockList">
 <table class="typeSummary" border="0" cellpadding="3" cellspacing="0" summary="Class Summary table, listing classes, and an explanation">
 <caption><span>Class Summary</span><span class="tabEnd">&nbsp;</span></caption>
 <tr>
 <th class="colFirst" scope="col">Class</th>
 <th class="colLast" scope="col">Description</th>
 </tr>
 <tbody>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/AttributesFactory.html" title="class in org.apache.geode.cache">AttributesFactory</a>&lt;K,V&gt;</td>
 <td class="colLast">Deprecated
 <div class="block"><span class="deprecationComment">as of 6.5 use <a href="../../../../org/apache/geode/cache/Cache.html#createRegionFactory-org.apache.geode.cache.RegionShortcut-"><code>Cache.createRegionFactory(RegionShortcut)</code></a> or
              <a href="../../../../org/apache/geode/cache/client/ClientCache.html#createClientRegionFactory-org.apache.geode.cache.client.ClientRegionShortcut-"><code>ClientCache.createClientRegionFactory(ClientRegionShortcut)</code></a> instead.</span></div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/CacheFactory.html" title="class in org.apache.geode.cache">CacheFactory</a></td>
 <td class="colLast">
 <div class="block">Factory class used to create the singleton <a href="../../../../org/apache/geode/cache/Cache.html" title="interface in org.apache.geode.cache"><code>cache</code></a> and connect to the GemFire
  singleton <a href="../../../../org/apache/geode/distributed/DistributedSystem.html" title="class in org.apache.geode.distributed"><code>distributed system</code></a>.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/DataPolicy.html" title="class in org.apache.geode.cache">DataPolicy</a></td>
 <td class="colLast">
 <div class="block">Enumerated type for region data policy.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/DiskWriteAttributesFactory.html" title="class in org.apache.geode.cache">DiskWriteAttributesFactory</a></td>
 <td class="colLast">Deprecated
 <div class="block"><span class="deprecationComment">as of 6.5 use <a href="../../../../org/apache/geode/cache/DiskStoreFactory.html" title="interface in org.apache.geode.cache"><code>DiskStoreFactory</code></a> instead</span></div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/DynamicRegionFactory.html" title="class in org.apache.geode.cache">DynamicRegionFactory</a></td>
 <td class="colLast">Deprecated
 <div class="block"><span class="deprecationComment">This class is deprecated.</span></div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/DynamicRegionFactory.Config.html" title="class in org.apache.geode.cache">DynamicRegionFactory.Config</a></td>
 <td class="colLast">
 <div class="block">Configuration for dynamic region factory.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/EvictionAction.html" title="class in org.apache.geode.cache">EvictionAction</a></td>
 <td class="colLast">
 <div class="block">The action that an <a href="../../../../org/apache/geode/cache/EvictionAlgorithm.html" title="class in org.apache.geode.cache"><code>EvictionAlgorithm</code></a> takes.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/EvictionAlgorithm.html" title="class in org.apache.geode.cache">EvictionAlgorithm</a></td>
 <td class="colLast">
 <div class="block">The algorithm used to determine when to perform an <a href="../../../../org/apache/geode/cache/EvictionAction.html" title="class in org.apache.geode.cache"><code>EvictionAction</code></a></div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/EvictionAttributes.html" title="class in org.apache.geode.cache">EvictionAttributes</a></td>
 <td class="colLast">
 <div class="block">
  Attributes that describe how a <code>Region</code>'s size is managed through an eviction
  controller.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/ExpirationAction.html" title="class in org.apache.geode.cache">ExpirationAction</a></td>
 <td class="colLast">
 <div class="block">Enumerated type for expiration actions.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/ExpirationAttributes.html" title="class in org.apache.geode.cache">ExpirationAttributes</a></td>
 <td class="colLast">
 <div class="block">Immutable parameter object for accessing and setting the attributes associated with
  <code>timeToLive</code> and <code>idleTimeout</code>.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/FixedPartitionAttributes.html" title="class in org.apache.geode.cache">FixedPartitionAttributes</a></td>
 <td class="colLast">
 <div class="block">Composite date type used to distribute the attributes for a fixed partition.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/InterestPolicy.html" title="class in org.apache.geode.cache">InterestPolicy</a></td>
 <td class="colLast">
 <div class="block">Enumerated type for region subscription interest policy.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/InterestResultPolicy.html" title="class in org.apache.geode.cache">InterestResultPolicy</a></td>
 <td class="colLast">
 <div class="block">Class <code>InterestResultPolicy</code> is an enumerated type for a register interest result.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/LossAction.html" title="class in org.apache.geode.cache">LossAction</a></td>
 <td class="colLast">Deprecated
 <div class="block"><span class="deprecationComment">this feature is scheduled to be removed</span></div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/MembershipAttributes.html" title="class in org.apache.geode.cache">MembershipAttributes</a></td>
 <td class="colLast">Deprecated
 <div class="block"><span class="deprecationComment">this feature is scheduled to be removed</span></div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/MirrorType.html" title="class in org.apache.geode.cache">MirrorType</a></td>
 <td class="colLast">Deprecated
 <div class="block"><span class="deprecationComment">as of GemFire 5.0, use <a href="../../../../org/apache/geode/cache/DataPolicy.html" title="class in org.apache.geode.cache"><code>DataPolicy</code></a> instead.</span></div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/Operation.html" title="class in org.apache.geode.cache">Operation</a></td>
 <td class="colLast">
 <div class="block">Enumerated type for an event operation.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/PartitionAttributesFactory.html" title="class in org.apache.geode.cache">PartitionAttributesFactory</a>&lt;K,V&gt;</td>
 <td class="colLast">
 <div class="block">
  A factory that creates instances of <a href="../../../../org/apache/geode/cache/PartitionAttributes.html" title="interface in org.apache.geode.cache"><code>PartitionAttributes</code></a> which are used to create a
  partitioned <a href="../../../../org/apache/geode/cache/Region.html" title="interface in org.apache.geode.cache"><code>Region</code></a>.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/RegionFactory.html" title="class in org.apache.geode.cache">RegionFactory</a>&lt;K,V&gt;</td>
 <td class="colLast">
 <div class="block"><code>RegionFactory</code> is used to create <a href="../../../../org/apache/geode/cache/Region.html" title="interface in org.apache.geode.cache"><code>regions</code></a> in a <a href="../../../../org/apache/geode/cache/Cache.html" title="interface in org.apache.geode.cache"><code>cache</code></a>.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/RequiredRoles.html" title="class in org.apache.geode.cache">RequiredRoles</a></td>
 <td class="colLast">Deprecated
 <div class="block"><span class="deprecationComment">this feature is scheduled to be removed</span></div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/ResumptionAction.html" title="class in org.apache.geode.cache">ResumptionAction</a></td>
 <td class="colLast">Deprecated
 <div class="block"><span class="deprecationComment">this API is scheduled to be removed</span></div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/Scope.html" title="class in org.apache.geode.cache">Scope</a></td>
 <td class="colLast">
 <div class="block">Enumerated type for region distribution scope.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/SubscriptionAttributes.html" title="class in org.apache.geode.cache">SubscriptionAttributes</a></td>
 <td class="colLast">
 <div class="block">Configuration attributes for defining subscriber requirements and behavior for a
  <code>Region</code>.</div>
 </td>
 </tr>
 </tbody>
 </table>
 </li>
 <li class="blockList">
 <table class="typeSummary" border="0" cellpadding="3" cellspacing="0" summary="Enum Summary table, listing enums, and an explanation">
 <caption><span>Enum Summary</span><span class="tabEnd">&nbsp;</span></caption>
 <tr>
 <th class="colFirst" scope="col">Enum</th>
 <th class="colLast" scope="col">Description</th>
 </tr>
 <tbody>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/RegionShortcut.html" title="enum in org.apache.geode.cache">RegionShortcut</a></td>
 <td class="colLast">
 <div class="block">Each enum represents a predefined <code>RegionAttributes</code> in a <code>Cache</code>.</div>
 </td>
 </tr>
 </tbody>
 </table>
 </li>
 <li class="blockList">
 <table class="typeSummary" border="0" cellpadding="3" cellspacing="0" summary="Exception Summary table, listing exceptions, and an explanation">
 <caption><span>Exception Summary</span><span class="tabEnd">&nbsp;</span></caption>
 <tr>
 <th class="colFirst" scope="col">Exception</th>
 <th class="colLast" scope="col">Description</th>
 </tr>
 <tbody>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/CacheClosedException.html" title="class in org.apache.geode.cache">CacheClosedException</a></td>
 <td class="colLast">
 <div class="block">Indicates that the caching system has been closed.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/CacheException.html" title="class in org.apache.geode.cache">CacheException</a></td>
 <td class="colLast">
 <div class="block">A generic exception, which indicates a cache error has occurred.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/CacheExistsException.html" title="class in org.apache.geode.cache">CacheExistsException</a></td>
 <td class="colLast">
 <div class="block">Thrown when attempting to create a <a href="../../../../org/apache/geode/cache/Cache.html" title="interface in org.apache.geode.cache"><code>Cache</code></a> if one already exists.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/CacheLoaderException.html" title="class in org.apache.geode.cache">CacheLoaderException</a></td>
 <td class="colLast">
 <div class="block">Thrown from the <a href="../../../../org/apache/geode/cache/CacheLoader.html#load-org.apache.geode.cache.LoaderHelper-"><code>CacheLoader.load(org.apache.geode.cache.LoaderHelper&lt;K, V&gt;)</code></a> method indicating that an error occurred when a
  CacheLoader was attempting to load a value.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/CacheRuntimeException.html" title="class in org.apache.geode.cache">CacheRuntimeException</a></td>
 <td class="colLast">
 <div class="block">A generic runtime exception that indicates a cache error has occurred.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/CacheWriterException.html" title="class in org.apache.geode.cache">CacheWriterException</a></td>
 <td class="colLast">
 <div class="block">An exception thrown by a <code>CacheWriter</code> method.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/CacheXmlException.html" title="class in org.apache.geode.cache">CacheXmlException</a></td>
 <td class="colLast">
 <div class="block">Thrown when a problem is encountered while parsing a
  <A href="package-summary.html#declarative">declarative caching XML file</A>.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/CommitConflictException.html" title="class in org.apache.geode.cache">CommitConflictException</a></td>
 <td class="colLast">
 <div class="block">Thrown when a commit fails due to a write conflict.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/CommitDistributionException.html" title="class in org.apache.geode.cache">CommitDistributionException</a></td>
 <td class="colLast">
 <div class="block">Indicates that an attempt to notify required participants of a transaction involving one or more
  regions that are configured with <a href="../../../../org/apache/geode/cache/MembershipAttributes.html" title="class in org.apache.geode.cache"><code>MembershipAttributes</code></a> may have failed.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/CommitIncompleteException.html" title="class in org.apache.geode.cache">CommitIncompleteException</a></td>
 <td class="colLast">
 <div class="block">Thrown when a commit fails to complete due to errors</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/DiskAccessException.html" title="class in org.apache.geode.cache">DiskAccessException</a></td>
 <td class="colLast">
 <div class="block">Indicates that an <code>IOException</code> during a disk region operation.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/DuplicatePrimaryPartitionException.html" title="class in org.apache.geode.cache">DuplicatePrimaryPartitionException</a></td>
 <td class="colLast">
 <div class="block">This exception is thrown when two nodes are defined with same primary partitions</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/EntryDestroyedException.html" title="class in org.apache.geode.cache">EntryDestroyedException</a></td>
 <td class="colLast">
 <div class="block">Indicates that a method was invoked on an entry that has been destroyed.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/EntryExistsException.html" title="class in org.apache.geode.cache">EntryExistsException</a></td>
 <td class="colLast">
 <div class="block">Thrown when attempting to create a <code>Region.Entry</code> that already exists in the
  <code>Region</code>.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/EntryNotFoundException.html" title="class in org.apache.geode.cache">EntryNotFoundException</a></td>
 <td class="colLast">
 <div class="block">Thrown when an operation is invoked on <code>Region</code> for an entry that doesn't exist in the
  <code>Region</code>.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/FailedSynchronizationException.html" title="class in org.apache.geode.cache">FailedSynchronizationException</a></td>
 <td class="colLast">
 <div class="block">Thrown when a cache transaction fails to register with the <code>UserTransaction</code> (aka JTA
  transaction), most likely the cause of the <code>UserTransaction</code>'s
  <code>javax.transaction.Status#STATUS_MARKED_ROLLBACK</code> status.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/GatewayConfigurationException.html" title="class in org.apache.geode.cache">GatewayConfigurationException</a></td>
 <td class="colLast">
 <div class="block">An exception indicating that a gateway configuration will not work with the remote side of the
  gateway's configuration.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/GatewayException.html" title="class in org.apache.geode.cache">GatewayException</a></td>
 <td class="colLast">
 <div class="block">An exception thrown by a <code>Gateway</code>.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/IncompatibleVersionException.html" title="class in org.apache.geode.cache">IncompatibleVersionException</a></td>
 <td class="colLast">
 <div class="block">An <code>IncompatibleVersionException</code> that the client version was not compatible with the
  server version.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/LowMemoryException.html" title="class in org.apache.geode.cache">LowMemoryException</a></td>
 <td class="colLast">
 <div class="block">Indicates a low memory condition either on the local or a remote <a href="../../../../org/apache/geode/cache/Cache.html" title="interface in org.apache.geode.cache"><code>Cache</code></a>.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/NoQueueServersAvailableException.html" title="class in org.apache.geode.cache">NoQueueServersAvailableException</a></td>
 <td class="colLast">
 <div class="block">Indicates that this client cannot contact any queue servers and therefore cannot perform
  operations that require a queue, such as registering interest.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/NoSubscriptionServersAvailableException.html" title="class in org.apache.geode.cache">NoSubscriptionServersAvailableException</a></td>
 <td class="colLast">
 <div class="block">Indicates that this client cannot contact any servers and therefore cannot perform operations
  that require subscriptions, such as registering interest.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/OperationAbortedException.html" title="class in org.apache.geode.cache">OperationAbortedException</a></td>
 <td class="colLast">
 <div class="block">Indicates that the operation that would have otherwise affected the cache has been aborted.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/PartitionedRegionDistributionException.html" title="class in org.apache.geode.cache">PartitionedRegionDistributionException</a></td>
 <td class="colLast">
 <div class="block">Indicates a failure to perform a distributed operation on a Partitioned Region after multiple
  attempts.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/PartitionedRegionStorageException.html" title="class in org.apache.geode.cache">PartitionedRegionStorageException</a></td>
 <td class="colLast">
 <div class="block">Description of the conditions under which this exception is thrown</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/RegionAccessException.html" title="class in org.apache.geode.cache">RegionAccessException</a></td>
 <td class="colLast">Deprecated
 <div class="block"><span class="deprecationComment">the MembershipAttributes API is scheduled to be removed</span></div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/RegionDestroyedException.html" title="class in org.apache.geode.cache">RegionDestroyedException</a></td>
 <td class="colLast">
 <div class="block">Indicates that the region has been destroyed.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/RegionDistributionException.html" title="class in org.apache.geode.cache">RegionDistributionException</a></td>
 <td class="colLast">Deprecated
 <div class="block"><span class="deprecationComment">the MembershipAttributes API is scheduled to be removed</span></div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/RegionExistsException.html" title="class in org.apache.geode.cache">RegionExistsException</a></td>
 <td class="colLast">
 <div class="block">Indicates that the requested region already exists when a region is being created.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/RegionReinitializedException.html" title="class in org.apache.geode.cache">RegionReinitializedException</a></td>
 <td class="colLast">
 <div class="block">Indicates that the region has been reinitialized.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/RegionRoleException.html" title="class in org.apache.geode.cache">RegionRoleException</a></td>
 <td class="colLast">Deprecated
 <div class="block"><span class="deprecationComment">this feature is scheduled to be removed</span></div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/ResourceException.html" title="class in org.apache.geode.cache">ResourceException</a></td>
 <td class="colLast">
 <div class="block">A Generic exception to indicate that a resource exception has occurred.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/RoleException.html" title="class in org.apache.geode.cache">RoleException</a></td>
 <td class="colLast">Deprecated
 <div class="block"><span class="deprecationComment">this feature is scheduled to be removed</span></div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/StatisticsDisabledException.html" title="class in org.apache.geode.cache">StatisticsDisabledException</a></td>
 <td class="colLast">
 <div class="block">Thrown if statistics are requested when statistics are disabled on the region.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/SynchronizationCommitConflictException.html" title="class in org.apache.geode.cache">SynchronizationCommitConflictException</a></td>
 <td class="colLast">
 <div class="block">Thrown when a commit operation of a JTA enlisted cache transaction fails</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/TimeoutException.html" title="class in org.apache.geode.cache">TimeoutException</a></td>
 <td class="colLast">
 <div class="block">Thrown if a <code>netSearch</code> times out without getting a response back from a cache, or
  when attempting to acquire a distributed lock.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/TransactionDataNodeHasDepartedException.html" title="class in org.apache.geode.cache">TransactionDataNodeHasDepartedException</a></td>
 <td class="colLast">
 <div class="block">Thrown when the transactional data host has shutdown or no longer has the data being modified by
  the transaction.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/TransactionDataNotColocatedException.html" title="class in org.apache.geode.cache">TransactionDataNotColocatedException</a></td>
 <td class="colLast">
 <div class="block">Indicates that an attempt was made to transactionally modify multiple keys that are not colocated
  on the same data host.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/TransactionDataRebalancedException.html" title="class in org.apache.geode.cache">TransactionDataRebalancedException</a></td>
 <td class="colLast">
 <div class="block">Thrown when a <a href="../../../../org/apache/geode/cache/control/RebalanceOperation.html" title="interface in org.apache.geode.cache.control"><code>RebalanceOperation</code></a> occurs concurrently with a transaction.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/TransactionException.html" title="class in org.apache.geode.cache">TransactionException</a></td>
 <td class="colLast">
 <div class="block">This is the superclass for all Exceptions that may be thrown by a GemFire transaction.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/TransactionInDoubtException.html" title="class in org.apache.geode.cache">TransactionInDoubtException</a></td>
 <td class="colLast">
 <div class="block">This Exception is thrown in presence of node failures, when GemFire cannot know with certainty
  about the outcome of the transaction.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/TransactionWriterException.html" title="class in org.apache.geode.cache">TransactionWriterException</a></td>
 <td class="colLast">
 <div class="block">Exception thrown by implementors of <a href="../../../../org/apache/geode/cache/TransactionWriter.html#beforeCommit-org.apache.geode.cache.TransactionEvent-"><code>TransactionWriter.beforeCommit(org.apache.geode.cache.TransactionEvent)</code></a> to signal that the
  current transaction should be aborted.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/UnsupportedOperationInTransactionException.html" title="class in org.apache.geode.cache">UnsupportedOperationInTransactionException</a></td>
 <td class="colLast">
 <div class="block">Indicates that an attempt was mode to invoke an operation that is not allowed in a transaction.</div>
 </td>
 </tr>
 <tr class="rowColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/UnsupportedVersionException.html" title="class in org.apache.geode.cache">UnsupportedVersionException</a></td>
 <td class="colLast">
 <div class="block">An <code>UnsupportedVersionException</code> indicates an unsupported version.</div>
 </td>
 </tr>
 <tr class="altColor">
 <td class="colFirst"><a href="../../../../org/apache/geode/cache/VersionException.html" title="class in org.apache.geode.cache">VersionException</a></td>
 <td class="colLast">
 <div class="block">An <code>VersionException</code> is an exception that indicates a client / server version
  mismatch exception has occurred.</div>
 </td>
 </tr>
 </tbody>
 </table>
 </li>
 </ul>
 <a name="package.description">
 <!--   -->
 </a>
 <h2 title="Package org.apache.geode.cache Description">Package org.apache.geode.cache Description</h2>
 <div class="block"><p>Provides an implementation of distributed object caching that
 can leverage GemFire's distribution capabilities. Refer to
 the programmer's guide for performance guidelines.</p>

 <a name="top">
 <ul>
 <li><a href="#functions">Function Execution</a></li>
 <li><a href="#distcache">Distributed Caching</a></li>
 <li><a href="#regions">Cache Regions</a></li>
 <li><a href="#partition">Partitioned Regions</a></li>
 <li><a href="#entries">Region Entries</a></li>
 <li><a href="#consistency">Distribution and Consistency Models</a></li>
 <li><a href="#storage">Storage Model</a></li>
 <li><a href="#loader">Cache Loaders</a></li>
 <li><a href="#cachewriter">Cache Writers</a></li>
 <li><a href="#expiration">Expiration</a></li>
 <li><a href="#event">Cache Events</a></li>
 <li><a href="#eviction">Eviction Attributes</a></li>
 <li><a href="#statistics">Statistics</a></li>
 <li><a href="#declarative">Declarative Caching</a></li>
 <li><a href="#clientServer">Client/Server Caching</a></li>
 <li><a href="#tx">Cache Transactions</a></li>
 <li><a href="#membership">Membership Attributes</a></li>
 </ul>

 <a name="functions"><h2>Function Execution</h2><a href="#top">Back to
 Top</a>

 <p>Function execution facilitates movement of behavior in the form of
 <a href="../../../../org/apache/geode/cache/execute/Function.html" title="interface in org.apache.geode.cache.execute">Function</a>s executed using the
 <a href="../../../../org/apache/geode/cache/execute/FunctionService.html" title="class in org.apache.geode.cache.execute">Function Execution Service</a>.  A Function may generate results from
 parallel execution on many <a href="../../../../org/apache/geode/cache/execute/FunctionService.html#onMembers-java.lang.String...-">members</a>
 , or several <a href="../../../../org/apache/geode/cache/execute/FunctionService.html#onServers-org.apache.geode.cache.client.Pool-">Cache Servers</a>, or perhaps evaluating <a href="../../../../org/apache/geode/cache/execute/FunctionService.html#onRegion-org.apache.geode.cache.Region-"><code>Region</code></a> data.  A <a href="../../../../org/apache/geode/cache/execute/ResultCollector.html" title="interface in org.apache.geode.cache.execute">ResultCollector</a> collects and
 possibly processes those results for consumption.  For more information look to the
 <a href="../../../../org/apache/geode/cache/execute/package-summary.html#package_description">org.apache.geode.cache.execute</a> package.
 </p>

 <a name="distcache"><h2>Distributed Caching</h2><a href="#top">Back to Top</a>

 <!-- Architecture diagram that shows multiple VMs in the same
 distributed system -->

 <p>GemFire's distributed caching implementation allows application data to be
 efficiently shared among multiple threads in a VM, multiple VMs
 running on the same physical machine, and multiple VMs running on
 multiple machines.  Cached data resides in "regions" whose
 contents are stored in a VM's heap.</p>
 <p>The <a href="../../../../org/apache/geode/cache/CacheFactory.html" title="class in org.apache.geode.cache"><code>CacheFactory</code></a> class provides
 the entry point to the caching API.  A <code>CacheFactory</code> is
 configured to create a <a href="../../../../org/apache/geode/cache/Cache.html" title="interface in org.apache.geode.cache">"cache instance"</a> that resides in the VM.  The cache factory also allows
 the <a href="../../../../org/apache/geode/distributed/DistributedSystem.html" title="class in org.apache.geode.distributed"><code>DistributedSystem</code></a> to be configured.</p>

 <a name="regions"><h2>Cache Regions</h2></a><a href="#top">Back to Top</a>

 <p>Application data is cached in a <a href="../../../../org/apache/geode/cache/Region.html" title="interface in org.apache.geode.cache">"region"</a>.  The <a href="../../../../org/apache/geode/cache/RegionFactory.html" title="class in org.apache.geode.cache"><code>RegionFactory</code></a> class provides the simpliest
 entry point into the <a href="../../../../org/apache/geode/cache/Region.html" title="interface in org.apache.geode.cache">Region</a>
 API. A <a href="../../../../org/apache/geode/cache/Region.html" title="interface in org.apache.geode.cache"><code>Region</code></a> implements <a href="https://docs.oracle.com/javase/8/docs/api/java/util/Map.html?is-external=true" title="class or interface in java.util"><code>Map</code></a>,
 however, it also provides caching behavior such as data loading,
 eviction control, and distribution.  Every region has a name and
 regions may be nested to provide a cache-naming hierarchy ("parent
 regions" with "subregions").  The root regions of the naming hierarchy
 (that is, the regions with no parent) are obtained with the <a href="../../../../org/apache/geode/cache/RegionService.html#rootRegions--"><code>RegionService.rootRegions()</code></a> method.
 Any region may be obtained with the <a href="../../../../org/apache/geode/cache/RegionService.html#getRegion-java.lang.String-"><code>RegionService.getRegion(java.lang.String)</code></a> method.</p>

 <p>Region properties such as the region's cache loader, data policy, and
 storage model are specified by an instance of <a href="../../../../org/apache/geode/cache/RegionAttributes.html" title="interface in org.apache.geode.cache"><code>RegionAttributes</code></a>.  A region
 <code>RegionAttributes</code> object can be specified when <a href="../../../../org/apache/geode/cache/Region.html#createSubregion-java.lang.String-org.apache.geode.cache.RegionAttributes-">creating</a> a
 region.</p>

 <a name="partition"><h2>Partitioned Regions</h2><a href="#top">Back to Top</a>

 <p>Region data can be partitioned across many distributed system members to create one large logical heap.
 The data policy must be set to <a href="../../../../org/apache/geode/cache/DataPolicy.html#PARTITION"><code>DataPolicy.PARTITION</code></a>
 or <a href="../../../../org/apache/geode/cache/DataPolicy.html#PERSISTENT_PARTITION"><code>DataPolicy.PERSISTENT_PARTITION</code></a>.
 <a href="../../../../org/apache/geode/cache/PartitionAttributes.html" title="interface in org.apache.geode.cache"><code>PartitionAttributes</code></a> are used to configure
 a partitioned region.  A partitioned region can be configured to be
 highly available, surviving the loss of one or more system members, by
 maintaining copies of data.  These extra copies also benefit read operations by
 allowing load balancing across all the copies.</p>

 <p>Partitioned Regions have the added feature of allowing storage
 sizes larger than a single Java VM can provide and with multiple
 Java VMs comes multiple garbage collectors, improving the performance of
 the entire Region in the face of a full garbage collection cycle.</p>
 </p>

 <p>Partitioned Regions support custom partitioning with the use of a
 <a href="../../../../org/apache/geode/cache/PartitionResolver.html" title="interface in org.apache.geode.cache"><code>PartitionResolver</code></a> and can be
 associated together or
 <a href="../../../../org/apache/geode/cache/PartitionAttributesFactory.html#setColocatedWith-java.lang.String-">colocated</a> to allow for efficient data usage.
 </p>

 <p>A <a href="../../../../org/apache/geode/cache/partition/PartitionRegionHelper.html" title="class in org.apache.geode.cache.partition"><code>PartitionRegionHelper</code></a>
 class provides methods to facilitate usage of Partitioned
 Regions with other features, for example when used in conjunction with <a
 href="#functions">function execution</a>.
 </p>

 <a name="entries"><h2>Region Entries</h2><a href="#top">Back to Top</a>

 <!-- Life cycle, constrained keys -->

 <p>A region contains key/value pairs of objects known as the region's
 <a href="../../../../org/apache/geode/cache/Region.Entry.html" title="interface in org.apache.geode.cache">"entries"</a>.  The
 <code>Region</code> class provides a number of methods for
 manipulating the region's entries such as <a href="../../../../org/apache/geode/cache/Region.html#create-K-V-"><code>create</code></a>, <a href="../../../../org/apache/geode/cache/Region.html#put-K-V-"><code>put</code></a>, <a href="../../../../org/apache/geode/cache/Region.html#invalidate-java.lang.Object-"><code>invalidate</code></a>, and <a href="../../../../org/apache/geode/cache/Region.html#destroy-java.lang.Object-"><code>destroy</code></a> .  The following
 diagram describes the life cycle of a region entry.</p>

 <CENTER>
 <IMG SRC="../../../../javadoc-images/entry-life-cycle.gif"
      WIDTH="598" HEIGHT="224"/>
 </CENTER>

 <a name="consistency"><h2>Distribution and Consistency Models</h2><a href="#top">Back to Top</a>

 <p>A region's <a href="../../../../org/apache/geode/cache/RegionAttributes.html#getScope--">scope</a> attribute
 determines how the region's entries will be distributed to other
 caches.  A region with <a href="../../../../org/apache/geode/cache/Scope.html#LOCAL">local</a> scope
 will not distribute any of its changes to any other members of the
 distributed system, nor will it receive changes when another cache
 instance is updated.</p>

 <p>When a change (such as a <code>put</code> or
 <code>invalidate</code>) is made to a region with non-local scope,
 that change is distributed to the other members of the distributed
 system that have created that region in their cache instance.  There
 are three kinds of distributed scope, each of which guarantees a
 different level of consistency for distributed data.  <a href="../../../../org/apache/geode/cache/Scope.html#GLOBAL">"Global"
 scope</a> provides the highest level of data consistency by obtaining a
 <a href="../../../../org/apache/geode/distributed/DistributedLockService.html" title="class in org.apache.geode.distributed">distributed lock</a> on a region entry before propagating a change to other
 members of the distributed system.  With globally-scoped regions, only
 one thread in the entire distributed system may modify the region entry at a
 time.</p>

 <p><a href="../../../../org/apache/geode/cache/Scope.html#DISTRIBUTED_ACK">"Distributed ACK" scope</a> provides slightly weaker data consistency
 than global scope.  With distributed ACK scope, the method that
 modifies the region (such as a call to <a href="../../../../org/apache/geode/cache/Region.html#destroy-java.lang.Object-"><code>Region.destroy(java.lang.Object)</code></a>) will not return until an
 acknowledgment of the change has been received from every member of
 the distributed system.  Multiple threads may modify the region
 concurrently, but the modifying thread may proceed knowing that its
 change to the region has been seen by all other members.</p>

 <p><a href="../../../../org/apache/geode/cache/Scope.html#DISTRIBUTED_NO_ACK">"Distributed NO ACK" scope</a> provides the weakest data consistency of
 all the scopes, but also provides the best performance.  A method invocation that
 modifies a region with distributed NO ACK scope will return
 immediately after it has updated the contents of the region in its own
 cache instance.  The updates are distributed
 asynchronously.</p>

 <a name="storage"><h2>Storage Model</h2><a href="#top">Back to Top</a>

 <p>The contents of a region (that is, the region's key/value pairs)
 may be stored in either the JVM's heap or on a disk drive.
 </p>

 <a name="dataPolicy"><h3>Data Policy</h3></a><a href="#top">Back to Top</a>

 <p>A region's <a href="../../../../org/apache/geode/cache/DataPolicy.html" title="class in org.apache.geode.cache">"data policy" attribute</a> determines if data is stored in the local cache.
 The <a href="../../../../org/apache/geode/cache/DataPolicy.html#NORMAL">normal policy</a>
 will store region data in the local cache.
 The <a href="../../../../org/apache/geode/cache/DataPolicy.html#EMPTY">empty policy</a>
 will never store region data in the local cache. They act as proxy regions that
 distribute write operations to others and receive events from others.
 The <a href="../../../../org/apache/geode/cache/DataPolicy.html#withReplication--">replication policies</a>
 may reduce the number of net searches that a caching application has to be perform,
 and can provide a backup mechanism. The replicated region initializes itself when
 it is created with the keys and value of the region as found in other caches.
 The <a href="../../../../org/apache/geode/cache/DataPolicy.html#REPLICATE">replicate policy</a> simply stores the relicate data in memory and
 the <a href="../../../../org/apache/geode/cache/DataPolicy.html#PERSISTENT_REPLICATE">persistent replicate policy</a> stores the data in memory and disk.
 The <a href="../../../../org/apache/geode/cache/DataPolicy.html#withPartitioning--">partition policies</a> are used for <a href="#partition">partitioned</a> regions.
 The <a href="../../../../org/apache/geode/cache/DataPolicy.html#PARTITION">partition policy</a> simply stores the <a href="#partition">partitioned</a> data in memory and
 the <a href="../../../../org/apache/geode/cache/DataPolicy.html#PERSISTENT_PARTITION">persistent partition policy</a> stores the <a href="#partition">partitioned</a> data in memory and disk.
 </p>

 <a name="storageOnDisk"><h3>Disk Storage</h3></a>

 <p>GemFire supports several modes of region persistence as determined by
 the <a href="../../../../org/apache/geode/cache/DataPolicy.html#withPersistence--">persistent data policies</a> and the <a href="../../../../org/apache/geode/cache/RegionAttributes.html#getEvictionAttributes--"><code>RegionAttributes.getEvictionAttributes()</code></a>'s <a href="../../../../org/apache/geode/cache/EvictionAction.html" title="class in org.apache.geode.cache">eviction action</a>
 of <a href="../../../../org/apache/geode/cache/EvictionAction.html#OVERFLOW_TO_DISK">overflow-to-disk</a>.
 The following table summarizes the different modes and their configuration.</p>

 <table border="1">

 <th>persistence</th>
 <th>overflow-to-disk</th>
 <th>mode</th>
 <th>description</th>

 <tr>
  <td>false</td>
  <td>false</td>
  <td>No Disk</td>
  <td>The cache <code>Region</code> persists no data to the disk.
      This is the default configuration.</td>
 </tr>

 <tr>
  <td>false</td>
  <td>true</td>
  <td>Disk for overflow only</td>
  <td>Once the amount of data stored in the region exceeds the eviction
      controller's threshold, least recently used data is written to
      disk and removed from the VM until the region's size is below the
      threshold.</td>
 </tr>

 <tr>
  <td>true</td>
  <td>false</td>
  <td>Disk for persistence</td>
  <td>All data in the region is <a href="../../../../org/apache/geode/cache/DiskStore.html" title="interface in org.apache.geode.cache">scheduled to be
      written</a> to disk as soon as it is placed in the region.  Thus,
      the data on disk contains a complete backup of the region.  No
      information about recently used data is maintained and,
      therefore, the size of the VM will continue to grow as more data
      is added to the region.  "Disk for persistence" mode is
      appropriate for situations in which the user wants to back up a
      region whose data fits completely in the VM.</td>
 </tr>

 <tr>
  <td>true</td>
  <td>true</td>
  <td>Disk for overflow and persistence</td>
  <td>All data in the region is <a href="../../../../org/apache/geode/cache/DiskStore.html" title="interface in org.apache.geode.cache">scheduled to be
      written</a> to disk as soon as it is placed in the region.  But
      unlike "disk for persistence" mode, the least recently used data will
      be removed from the VM once the eviction controller's
      threshold is reached.</td>
 </tr>

 </table>

 <p>There are several things to keep in mind when working with regions
 that store data on disk.</p>

 <UL>

 <LI>Operations (such as <a href="../../../../org/apache/geode/cache/Region.html#invalidate-java.lang.Object-"><code>invalidate</code></a> and <a href="../../../../org/apache/geode/cache/Region.html#destroy-java.lang.Object-"><code>Region.destroy(java.lang.Object)</code></a>) that remove data from the
 cache also remove data from disk.  In order for data to be removed
 from the VM and not from disk, <a href="../../../../org/apache/geode/cache/EvictionAction.html#OVERFLOW_TO_DISK">EvictionAction.OVERFLOW_TO_DISK</a>
 overflow} must be used.</LI>

 <LI>When disk overflow is enabled, only the <a href="../../../../org/apache/geode/cache/Region.Entry.html#getValue--">value</a> of the least
 recently used entry is removed from the VM.  That is, the entry's key
 and the entry itself remain in the VM.</LI>

 <LI>When disk overflow is enabled, and backup is not then in each
 disk directory files whose name start with <code>OVERFLOW_</code>
 will be created. These files are deleted automatically when they
 are no longer being used. If a VM crashes it may not clean up its
 overflow files. In that case they will be cleaned up the next time
 the same region is created.</LI>

 <LI>GemFire will look for the value of a region entry on disk before
 it will look in other cache instances.  That is, it will not perform a
 net search or a <a href="../../../../org/apache/geode/cache/CacheLoader.html#load-org.apache.geode.cache.LoaderHelper-">load</a> if the value exists
 on disk.</LI>

 <LI>When data is read from or written to disk, no <a href="../../../../org/apache/geode/cache/CacheEvent.html" title="interface in org.apache.geode.cache">cache events</a> are fired.</LI>

 <LI>Region operations such as <a href="../../../../org/apache/geode/cache/Region.html#destroy-java.lang.Object-">destroy</a> and <a href="../../../../org/apache/geode/cache/Region.html#invalidate-java.lang.Object-">invalidate</a> effect the
 data that is stored on disk in addition to the data stored in the VM.
 That is, if an entry is destroyed in the VM (even by an <a href="../../../../org/apache/geode/cache/ExpirationAction.html" title="class in org.apache.geode.cache"><code>ExpirationAction</code></a>), it will also be destroyed on disk.</LI>

 </UL>

 <h3>Region backup and restore</h3>

 Any GemFire resource that stores data on disk does so by configuring itself
 to use a <a href="../../../../org/apache/geode/cache/DiskStore.html" title="interface in org.apache.geode.cache"><code>disk store</code></a>.
 Disk stores are created using the
 <a href="../../../../org/apache/geode/cache/DiskStoreFactory.html" title="interface in org.apache.geode.cache"><code>disk store factory API</code></a> or by
 configuring them in XML using the "disk-store" element.

 Region's specify the disk store they are in by setting the
 <a href="../../../../org/apache/geode/cache/RegionAttributes.html#getDiskStoreName--"><code>disk store name region attribute</code></a>.

 <P>A <a href="../../../../org/apache/geode/cache/Region.html#put-K-V-">put</a> on a region
 that is configured to have a disk "backup" (by using a
 <a href="../../../../org/apache/geode/cache/DataPolicy.html#withPersistence--">persistent data policy</a>)
  will result in the immediate scheduling of a
 disk write according to the region's <a href="../../../../org/apache/geode/cache/DiskStore.html" title="interface in org.apache.geode.cache"><code>disk store</code></a>
 and the  <a href="../../../../org/apache/geode/cache/RegionAttributes.html#isDiskSynchronous--">disk synchronous region attribute</a>.</P>

 <P>The actual backup data is stored in each of the disk store's specified disk
 directories. If any one of these directories runs out of space then
 any further writes to the backed up region will fail with a
 DiskAccessException. The actual file names begin with <code>BACKUP_</code>.
 If you wish to store a backup in another location
 or offline, then all of these files need to be saved. All of the files
 in the same directory must always be kept together in the same directory.
 It is ok to change the directory name.

 <P>When a region with a disk backup is created, it initializes itself
 with a "bulk load" operation that reads region entry data from its
 disk files.  Note that the bulk load operation does not create cache
 events and it does not send update messages to other members of the
 distributed system.  Bulk loading reads both the key and value
 of each region entry into memory.
 If region also has overflow-to-disk enabled then it will only load values
 until the LRU limit is reached.
 If the system property "gemfire.disk.recoverValues"
 is set to "false" then the entry values will
 not be loaded into memory during the bulk load
 but will be lazily read into the VM as they are requested.</P>

 <P>A common high-availability scenario may involve replicated regions
 that are configured to have disk backups.  When a replicated backup
 region is created in a distributed system that already contains a
 replicated backup region, GemFire optimizes the initialization of the
 backup region by streaming the contents of the backup file to the
 region being initialized.  If there is no other replicated backup region
 in the distributed system, the backup file for the region being
 initialized may contain stale data.  (That is, the value of region
 entries may have changed while the backup VM was down.)  In this
 situation, the region being initialized will consult other VMs in the
 distributed system to obtain an up-to-date version of the cached
 data.</P>

 <a name="loader"><h2>Cache Loaders</h2></a><a href="#top">Back to Top</a>

 <!-- CacheLoader, netSearch, netLoad -->

 <p>A <a href="../../../../org/apache/geode/cache/CacheLoader.html" title="interface in org.apache.geode.cache">cache loader</a>
 allows data from outside of the VM to be placed into a region.  When
 <a href="../../../../org/apache/geode/cache/Region.html#get-java.lang.Object-"><code>Region.get(java.lang.Object)</code></a> is called for a region
 entry that has a <code>null</code> value, the <a href="../../../../org/apache/geode/cache/CacheLoader.html#load-org.apache.geode.cache.LoaderHelper-"><code>load</code></a> method of the
 region's cache loader is invoked.  The <code>load</code> method
 creates the value for the desired key by performing an operation such
 as a database query.  The <code>load</code> may also perform a
 <a href="../../../../org/apache/geode/cache/LoaderHelper.html#netSearch-boolean-">net
 search</a> that will look for the value in a cache instance hosted by
 another member of the distributed system.</p>

 <p>If a region was not created with a user-specified cache loader, the
 <code>get</code> operation will, by default, perform a special
 variation of net search: if the value cannot be found in any of the
 members of the distributed system, but one of those members has
 defined a cache loader for the region, then that remote cache loader
 will be invoked (a "net load") and the loaded value returned to the
 requester.  Note that a net load does not store the loaded value in
 the remote cache's region.</p>

 <a name="cachewriter"><h2>Cache Writers</h2><a href="#top">Back to Top</a>

 <p>The <a href="../../../../org/apache/geode/cache/CacheWriter.html" title="interface in org.apache.geode.cache"><code>CacheWriter</code></a> is a type of event handler
 that is invoked <em>synchronously before</em> the cache is modified, and has
 the ability to abort the operation. Only one CacheWriter in the distributed system
 is invoked before the operation that would modify a cache. A CacheWriter
 is typically used to update an external database.</p>

 <a name="expiration"><h2>Expiration</h2></a><a href="#top">Back to Top</a>

 <p>Sometimes cached data has a limited lifetime.  The region attributes
 <a href="../../../../org/apache/geode/cache/RegionAttributes.html#getRegionTimeToLive--">regionTimeToLive</a>, <a href="../../../../org/apache/geode/cache/RegionAttributes.html#getRegionIdleTimeout--">regionIdleTimeout</a>, <a href="../../../../org/apache/geode/cache/RegionAttributes.html#getEntryTimeToLive--">entryTimeToLive</a>, and <a href="../../../../org/apache/geode/cache/RegionAttributes.html#getEntryIdleTimeout--">entryIdleTimeout</a>, specify how data is handled when it becomes too
 old.  There are two conditions under which cache data is considered
 too old: data has resided unchanged in a region for a given amount of time
 ("time to
 live") and data has not been accessed for a given amount of time
 ("idle
 time").  GemFire's caching implementation launches an "expiration
 thread" that periodically monitors region entries and will expire
 those that have become too old.  When a region entry expires, it can
 either be <a href="../../../../org/apache/geode/cache/ExpirationAction.html#INVALIDATE">invalidated</a>,  <a href="../../../../org/apache/geode/cache/ExpirationAction.html#DESTROY">destroyed</a>, <a href="../../../../org/apache/geode/cache/ExpirationAction.html#LOCAL_INVALIDATE">locally
 invalidated</a>, or <a href="../../../../org/apache/geode/cache/ExpirationAction.html#LOCAL_DESTROY">locally destroyed</a>.</p>

 <a name="event"><h2>Cache Events</h2></a><a href="#top">Back to Top</a>

 <p>The <a href="../../../../org/apache/geode/cache/CacheListener.html" title="interface in org.apache.geode.cache"><code>CacheListener</code></a>
 interface provides callback methods that are invoked synchronously in
 response to certain operations (such as a <code>put</code> or
 <code>invalidate</code>) being performed on a region.  The event
 listener for a region is specified with the <a href="../../../../org/apache/geode/cache/AttributesFactory.html#setCacheListener-org.apache.geode.cache.CacheListener-"><code>setCacheListener</code></a> method.  Each callback method on the
 <code>CacheListener</code> receives a <a href="../../../../org/apache/geode/cache/CacheEvent.html" title="interface in org.apache.geode.cache"><code>CacheEvent</code></a> describing the operation
 that caused the callback to be invoked and possibly containing information
 relevant to the operation
 (such as the old and new values of a region entry).</p>

 <a name="eviction"><h2>Eviction Attributes</h2><a href="#top">Back to Top</a>

 <p>Before a new entry is created in a region, the region's eviction controller
  is consulted.  The eviction controller may perform some action on the region (usually an
 action that makes the region smaller) based on certain criteria.  For
 instance, an eviction controller could keep track of the sizes of the
 entry values.  Before a new entry is added, the eviction controller
 could remove the entry with the largest value to free up space in
 the cache instance for new data.  GemFire provides <a href="../../../../org/apache/geode/cache/EvictionAttributes.html" title="class in org.apache.geode.cache"><code>EvictionAttributes</code></a> that will create an eviction controller
 that destroys the "least recently used" Region Entry once the Region
 exceeds a given number of entries.</p>

 <a name="statistics"><h2>Statistics</h2><a href="#top">Back to Top</a>

 <!-- API statistics and VSD statistics -->

 <p>The <a href="../../../../org/apache/geode/cache/CacheStatistics.html" title="interface in org.apache.geode.cache"><code>CacheStatistics</code></a> class
 provides statistics information about the usage of a region or entry.
 Statistics are often used by eviction controllers to determine which
 entries should be invalidated or destroyed when the region reaches its
 maximum size.</p>

 <a name="declarative"><h2>Declarative Caching</h2><a href="#top">Back to Top</a>

 <p>A "caching XML file" declares regions, entries, and attributes.  When
 a <code>Cache</code> is created its contents can be initialized
 according to a caching XML file.
 The top level element must be a cache element.
 </p>

 <p>The Document Type Definition for a declarative cache XML file can
 be found in <code>"doc-files/cache6_5.dtd"</code>. For examples of
 declarative cache XML files see <A
 href="../../../../javadoc-images/example-cache.xml">example1</A>, <A
 href="../../../../javadoc-images/example2-cache.xml">example2</A>, and <A
 href="../../../../javadoc-images/example3-cache.xml">example3</A>.

 <a name="clientServer"><h2>Client/Server Caching</h2><a href="#top">Back to Top</a>

 <p>GemFire caches can be configured in a client/server hierarchy.
 In this configuration, GemFire cache regions are configured as
 clients to regions in GemFire server caches running in a separate
 distributed system.
 The GemFire <a href="../../../../org/apache/geode/cache/server/package-summary.html#package_description">servers</a>
 are generally run as cacheserver processes.
 <a href="../../../../org/apache/geode/cache/client/package-summary.html#package_description">Clients</a>
 are configured with a
 <a href="../../../../org/apache/geode/cache/client/ClientCache.html" title="interface in org.apache.geode.cache.client">client cache</a>
 which has a default
 <a href="../../../../org/apache/geode/cache/client/Pool.html" title="interface in org.apache.geode.cache.client">pool</a>
 that manages connections to the server caches
 which are used by the client regions.
 When a client updates its region, the update is forwarded to the server.
 When a client get results in a local cache miss,
 the get request is forwarded to the server.
 The clients may also subscribe to server-side events.
 For more information on the client see the
 <a href="../../../../org/apache/geode/cache/client/package-summary.html#package_description">client</a>.
 For more information on the server see the
 <a href="../../../../org/apache/geode/cache/server/package-summary.html#package_description">server</a>.</p>

 <a name="tx"><h2>Cache Transactions</h2><a href="#top">Back to Top</a>

 <p>The GemFire cache supports transactions providing enhanced data
 consistency across multiple Regions.  GemFire Transactions are
 designed to run in a highly concurrent environment and as such have
 optimistic conflict behavior.  They are optimistic in the sense that
 they assume little data overlap between transactions.  Using that
 assumption, they do not reserve entries that are being changed by the
 transaction until the commit operation.  For example, when two
 transactions operate on the same Entry, the last one to commit will
 detect a conflict and fail to commit.  The changes made by the
 successful transaction are only available to other threads after the
 commit has finished, or in other words GemFire Transactions exhibit
 Read Committed behavior.</p>

 <p>To provide application integration with GemFire transactions, a
 <code>TransactionListener</code> with associated
 <code>TransactionEvents</code> is provided as a <code>Cache</code>
 attribute.  The listener is notified of commits, both failed and
 successful as well as explicit rollbacks.  When a commit message is
 received by a distributed member with the same Region, again the
 TransactionListener is invoked.

 <p>GemFire transactions also integrate well with JTA transactions.  If
 a JTA transaction has begun and an existing GemFire transaction is not
 already present, any transactional region operation will create a
 GemFire transaction and register it with the JTA transaction, causing
 the JTA transaction manager to take control of the GemFire
 commit/rollback operation.

 <p>Similar to JTA transactions, GemFire transactions are associated
 with a thread. Only one transaction is allowed at a time per thread
 and a transaction is not allowed to be shared amount threads.  The
 changes made changed by a GemFire transaction are distributed to other
 distributed memebers as per the Region's Scope.

 <p>Finally, GemFire transactions allow for the "collapse" of multiple
 operations on an Entry, for example if an application destroys an
 Entry and follows with a <code>create</code> operation and then a
 <code>put</code> operations, all three operations are combined into
 one action reflecting the sum of all three.

 <a name="membership"><h2>Membership Attributes</h2><a href="#top">Back to Top</a>

 <p>The GemFire region can be configured to require the
 presence of one or more user-defined membership roles.  Each <a href="../../../../org/apache/geode/distributed/Role.html" title="interface in org.apache.geode.distributed"><code>Role</code></a> is assigned to any number of
 applications when each application connects to the GemFire distributed
 system.  <a href="../../../../org/apache/geode/cache/MembershipAttributes.html" title="class in org.apache.geode.cache"><code>MembershipAttributes</code></a> are
 then used to specify which <a href="../../../../org/apache/geode/cache/MembershipAttributes.html#getRequiredRoles--">roles
 are required</a> to be online and present in that region's membership
 for access to the cache region being configured.</p>

 <p>In addition to specifying which roles are required,
 <code>MembershipAttributes</code> are used to specify the <a href="../../../../org/apache/geode/cache/LossAction.html" title="class in org.apache.geode.cache"><code>LossAction</code></a>. The loss action determines how
 access to the region is affected when one or more required roles are
 offline and no longer present in the system membership. The region can be
 made completely <a href="../../../../org/apache/geode/cache/LossAction.html#NO_ACCESS">"NO_ACCESS"</a>,
 which means that the application cannot read from or write to that region.
 <a href="../../../../org/apache/geode/cache/LossAction.html#LIMITED_ACCESS">"LIMITED_ACCESS"</a> means that the application cannot write to that region.
 <a href="../../../../org/apache/geode/cache/LossAction.html#FULL_ACCESS">"FULL_ACCESS"</a> means that the application can read from and write to that
 region as normal. If "FULL_ACCESS" is selected,
 then the application would only be aware of the missing required role if it
 registered a <a href="../../../../org/apache/geode/cache/RegionRoleListener.html" title="interface in org.apache.geode.cache"><code>RegionRoleListener</code></a>.
 This listener provides callbacks to notify the application when required
 roles are gained or lost, thus providing for custom integration of required
 roles with the application.</p>

 <p><a href="../../../../org/apache/geode/cache/ResumptionAction.html" title="class in org.apache.geode.cache"><code>ResumptionAction</code></a> defined in the
 <code>MembershipAttributes</code> specifies how the application responds
 to having a missing required role return to the distributed membership.
 <a href="../../../../org/apache/geode/cache/ResumptionAction.html#NONE">"None"</a>
 results in no special action, while <a href="../../../../org/apache/geode/cache/ResumptionAction.html#REINITIALIZE">"Reinitialize"</a>
 causes the region to be reinitialized.  Reinitializing the region will
 clear all entries from that region.  If it is a replicate, the
 region will repopulate with entries available from other distributed
 members.</p>

 <p><a href="../../../../org/apache/geode/cache/RequiredRoles.html" title="class in org.apache.geode.cache"><code>RequiredRoles</code></a> provides methods to
 check for missing required roles for a region and to wait until all required
 roles are present. In addition, this class can be used to check if a role
 is currently present in a region's membership.</p></div>
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