PersistenceQueryBuiltInAbstract.java

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 *  to you under the Apache License, Version 2.0 (the
 *  "License"); you may not use this file except in compliance
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 *        http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.isis.core.runtime.persistence.query;

import java.io.IOException;

import org.apache.isis.applib.query.Query;
import org.apache.isis.applib.query.QueryBuiltInAbstract;
import org.apache.isis.core.commons.encoding.DataInputExtended;
import org.apache.isis.core.metamodel.spec.ObjectSpecification;
import org.apache.isis.core.metamodel.specloader.SpecificationLoader;
import org.apache.isis.core.runtime.system.persistence.PersistenceQuery;

/**
 * Corresponds to {@link QueryBuiltInAbstract}.
 *
 * <p>
 * REVIEW: now that we've dropped remoting, could we get rid of the {@link PersistenceQuery} hierarchy
 * classes and just use the applib {@link Query} throughout?
 */
public abstract class PersistenceQueryBuiltInAbstract extends PersistenceQueryAbstract implements PersistenceQueryBuiltIn {

    protected long index;
    protected long countedSoFar;

    public PersistenceQueryBuiltInAbstract(
            final ObjectSpecification specification,
            final SpecificationLoader specificationLoader,
            final long... range) {
        super(specification, specificationLoader, range);
    }

    public PersistenceQueryBuiltInAbstract(
            final DataInputExtended input,
            final SpecificationLoader specificationLoader,
            final long... range) throws IOException {
        super(input, specificationLoader, range);
    }

    protected boolean matchesRange(final boolean ifMatches) {
        if (!ifMatches){
            return false;
        }
        
        if (getCount() == 0 && getStart() == 0){
            return true;
        }
        if (index++ < start){
            return false;
        }
        if (countedSoFar++ < count){
            return true;
        }
        return false;
    }
    
}