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Neo4j kernel is a lightweight, embedded Java database designed to store data structured as graphs rather than tables. For more information, see http://neo4j.org.

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/*
 * Copyright (c) "Neo4j"
 * Neo4j Sweden AB [https://neo4j.com]
 *
 * This file is part of Neo4j.
 *
 * Neo4j is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see .
 */
package org.neo4j.kernel.impl.newapi;

import org.neo4j.internal.kernel.api.PartitionedScan;
import org.neo4j.internal.kernel.api.TokenPredicate;
import org.neo4j.kernel.api.ExecutionContext;
import org.neo4j.kernel.api.index.IndexProgressor;
import org.neo4j.kernel.impl.index.schema.PartitionedTokenScan;

public class PartitionedTokenIndexCursorScan
        implements PartitionedScan, PartitionedTokenCursorScan {
    private final TokenPredicate query;
    private final PartitionedTokenScan tokenScan;

    PartitionedTokenIndexCursorScan(TokenPredicate query, PartitionedTokenScan tokenScan) {
        this.query = query;
        this.tokenScan = tokenScan;
    }

    @Override
    public int getNumberOfPartitions() {
        return tokenScan.getNumberOfPartitions();
    }

    @Override
    public boolean reservePartition(Cursor cursor, ExecutionContext executionContext) {
        final var indexCursor = (InternalTokenIndexCursor) cursor;
        indexCursor.initState(
                executionContext.dataRead(), executionContext.txStateHolder(), executionContext.accessModeProvider());
        final var indexProgressor = tokenScan.reservePartition(indexCursor, executionContext.cursorContext());
        if (indexProgressor == IndexProgressor.EMPTY) {
            return false;
        }
        indexCursor.initializeQuery(indexProgressor, query.tokenId(), null, null);
        return true;
    }

    @Override
    public PartitionedTokenScan getTokenScan() {
        return tokenScan;
    }
}