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* to you under the Apache License, Version 2.0 (the
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* http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.cayenne.lifecycle.cache;
import java.util.Collection;
import java.util.HashSet;
import java.util.Set;
import org.apache.cayenne.DataChannel;
import org.apache.cayenne.DataChannelFilter;
import org.apache.cayenne.DataChannelFilterChain;
import org.apache.cayenne.ObjectContext;
import org.apache.cayenne.QueryResponse;
import org.apache.cayenne.access.DataContext;
import org.apache.cayenne.annotation.PrePersist;
import org.apache.cayenne.annotation.PreRemove;
import org.apache.cayenne.annotation.PreUpdate;
import org.apache.cayenne.cache.QueryCache;
import org.apache.cayenne.graph.GraphDiff;
import org.apache.cayenne.query.Query;
/**
* A {@link DataChannelFilter} that invalidates cache groups defined for mapped entities
* via {@link CacheGroups} annotations.
*
* @since 3.1
*/
public class CacheInvalidationFilter implements DataChannelFilter {
private final ThreadLocal<Set<String>> groups = new ThreadLocal<Set<String>>();
public void init(DataChannel channel) {
// noop
}
public QueryResponse onQuery(
ObjectContext originatingContext,
Query query,
DataChannelFilterChain filterChain) {
return filterChain.onQuery(originatingContext, query);
}
public GraphDiff onSync(
ObjectContext originatingContext,
GraphDiff changes,
int syncType,
DataChannelFilterChain filterChain) {
try {
GraphDiff result = filterChain.onSync(originatingContext, changes, syncType);
// no exceptions, flush...
Collection<String> groupSet = groups.get();
if (groupSet != null && !groupSet.isEmpty()) {
// TODO: replace this with QueryCache injection once CAY-1445 is done
QueryCache cache = ((DataContext) originatingContext).getQueryCache();
for (String group : groupSet) {
cache.removeGroup(group);
}
}
return result;
}
finally {
groups.set(null);
}
}
/**
* A callback method that records cache group to flush at the end of the commit.
*/
@PrePersist(entityAnnotations = CacheGroups.class)
@PreRemove(entityAnnotations = CacheGroups.class)
@PreUpdate(entityAnnotations = CacheGroups.class)
protected void preCommit(Object object) {
Set<String> groupSet = groups.get();
if (groupSet == null) {
groupSet = new HashSet<String>();
groups.set(groupSet);
}
addCacheGroups(groupSet, object);
}
/**
* A method that builds a list of cache groups for a given object and adds them to the
* invalidation group set. This implementation adds all groups defined via
* {@link CacheGroups} annotation for a given class. Subclasses may override this
* method to provide more fine-grained filtering of cache groups to invalidate, based
* on the state of the object.
*/
protected void addCacheGroups(Set<String> groupSet, Object object) {
CacheGroups a = object.getClass().getAnnotation(CacheGroups.class);
for (String group : a.value()) {
groupSet.add(group);
}
}
}