com.tangosol.net.BackingMapContext Maven / Gradle / Ivy
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/*
* Copyright (c) 2000, 2022, Oracle and/or its affiliates.
*
* Licensed under the Universal Permissive License v 1.0 as shown at
* https://oss.oracle.com/licenses/upl.
*/
package com.tangosol.net;
import com.tangosol.util.InvocableMap;
import com.tangosol.util.MapIndex;
import com.tangosol.util.ObservableMap;
import com.tangosol.util.ValueExtractor;
import com.tangosol.util.WrapperObservableMap;
import com.tangosol.util.extractor.IndexAwareExtractor;
import java.util.Map;
/**
* The BackingMapContext provides an execution context to server side agents such
* as {@link com.tangosol.util.InvocableMap.EntryProcessor EntryProcessors} and
* {@link com.tangosol.util.InvocableMap.EntryAggregator EntryAggregators}.
* As of Coherence 3.7, this context is also used to initialize {@link
* IndexAwareExtractor pluggable indexes} to provide contextual knowledge about
* the backing map and cache for which the index is created.
*
* @since Coherence 3.7
* @author coh 2010.12.04
*/
public interface BackingMapContext
{
/**
* Return the "parent" {@link BackingMapManagerContext} for this context.
* Inversely, this context could be retrieved using the {@link
* BackingMapManagerContext#getBackingMapContext(String) getBackingMapContext}
* API.
*
* @return the enclosing {@link BackingMapManagerContext}
*/
public BackingMapManagerContext getManagerContext();
/**
* Return the name of the {@link NamedCache cache} that this BackingMapContext
* is associated with.
*
* @return the corresponding cache name
*/
public String getCacheName();
/**
* Return the backing map that this BackingMapContext is associated with.
* Most commonly it is the same map that is created by the {@link
* BackingMapManager#instantiateBackingMap(String) instantiateBackingMap} call.
* In the case the returned map is not {@link ObservableMap observable},
* it will be wrapped by the {@link WrapperObservableMap}.
*
* @return the corresponding backing map
*
* @deprecated As of Coherence 12.1.3, replaced with {@link #getBackingMapEntry}
*/
public ObservableMap getBackingMap();
/**
* Return a map of indexes defined for the {@link NamedCache cache} that
* this BackingMapContext is associated with. The returned map must be
* treated in the read-only manner.
*
* @return the map of indexes defined on the cache
*/
public Map getIndexMap();
/**
* Return an InvocableMap.Entry for the specified key (in its internal
* format) from the associated cache, obtaining exclusive access to that
* cache entry.
*
* This method may only be called within the context of an EntryProcessor
* invocation. Any changes made to the entry will be persisted with the same
* lifecycle as those made by the enclosing invocation. The returned entry
* is only valid for the duration of the enclosing invocation and multiple
* calls to this method within the same invocation context will return the
* same entry object.
*
* Because this method implicitly locks the specified cache entry, callers
* may use it to access, insert, update, modify, or remove cache entries
* from within the context of an EntryProcessor invocation. Operating on the
* entries returned by this method differs from operating directly against
* the backing map, as the returned entries provide an isolated,
* read-consistent view. The implicit lock acquisition attempted by this
* method could create a deadlock if entries are locked in conflicting
* orders on different threads. It is the caller's responsibility to ensure
* that cache entries are accessed (locked) in a deadlock-free manner.
*
* The usage of this method is highly encouraged instead of direct
* operations against the backing map retrieved by (now deprecated)
* {@link BackingMapManagerContext#getBackingMap(String)} method.
*
* @param oKey the key (in internal format) to obtain an entry for;
* must not be null
*
* @return an InvocableMap.Entry for the specified key, or null if the
* specified key is not owned by this service member
*
* @throws IllegalStateException if called from outside of an EntryProcessor
* invocation context
* @throws IllegalMonitorStateException if a deadlock is detected while
* attempting to obtain exclusive access to the entry
* @throws IllegalArgumentException if attempting to access an entry that
* does not belong to partition(s) associated with the caller's context
*/
public InvocableMap.Entry getBackingMapEntry(Object oKey);
/**
* Return a read-only InvocableMap.Entry for the specified key (in its internal
* format) from the associated cache.
*
* This method may be called within the context of an EntryProcessor or Aggregator
* invocation, and may result in a {@link com.tangosol.net.cache.CacheLoader#load(java.lang.Object)
* load}.
*
* Note: to infer whether the InvocableMap.Entry exists in the cache use
* {@link InvocableMap.Entry#isPresent()}
*
* @param oKey the key (in internal format) to obtain an entry for;
* must not be null
*
* @return an InvocableMap.Entry for the specified key, or null if the
* specified key is not owned by this service member
*
* @throws IllegalStateException if called from an inactive invocation context
*/
public InvocableMap.Entry getReadOnlyEntry(Object oKey);
}