cayenne-server/src/main/java/org/apache/cayenne/access/PrefetchObjectResolver.java

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package org.apache.cayenne.access;

import java.util.Map;

import org.apache.cayenne.DataRow;
import org.apache.cayenne.ObjectId;
import org.apache.cayenne.Persistent;
import org.apache.cayenne.reflect.ClassDescriptor;

/**
 * @since 4.0
 */
class PrefetchObjectResolver extends ObjectResolver {

    private Map<ObjectId, Persistent> seen;

    PrefetchObjectResolver(DataContext context, ClassDescriptor descriptor, boolean refresh,
            Map<ObjectId, Persistent> seen) {
        super(context, descriptor, refresh);
        this.seen = seen;
    }

    @Override
    Persistent objectFromDataRow(DataRow row, ObjectId anId, ClassDescriptor classDescriptor) {
        // skip processing of objects that were already processed in this
        // transaction, either by this node or by some other node...
        // added per CAY-1695 ..

        Persistent object = seen.get(anId);
        if (object == null) {
            object = super.objectFromDataRow(row, anId, classDescriptor);
            seen.put(anId, object);
        }

        return object;
    }

}