org.structr.core.graph.NodeServiceCommand.java Source code

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Here is the source code for org.structr.core.graph.NodeServiceCommand.java

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/**
 * Copyright (C) 2010-2016 Structr GmbH
 *
 * This file is part of Structr <http://structr.org>.
 *
 * Structr 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.
 *
 * Structr 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 Structr.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.structr.core.graph;

import java.util.Iterator;
import java.util.UUID;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.atomic.AtomicLong;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.apache.commons.lang3.StringUtils;
import org.structr.common.SecurityContext;
import org.structr.common.error.FrameworkException;
import org.structr.core.Command;
import org.structr.core.Predicate;
import org.structr.core.app.App;
import org.structr.core.app.StructrApp;

/**
 * Abstract base class for all graph service commands.
 *
 *
 */
public abstract class NodeServiceCommand extends Command {

    private static final Logger logger = Logger.getLogger(NodeServiceCommand.class.getName());
    private static final ArrayBlockingQueue<String> uuidQueue = new ArrayBlockingQueue<>(100000);

    @Override
    public Class getServiceClass() {
        return (NodeService.class);
    }

    /**
     * Executes the given operation on all nodes in the given list.
     *
     * @param <T>
     * @param securityContext
     * @param iterator the iterator that provides the nodes to operate on
     * @param commitCount
     * @param description
     * @param operation the operation to execute
     * @return the number of nodes processed
     */
    public static <T> long bulkGraphOperation(final SecurityContext securityContext, final Iterator<T> iterator,
            final long commitCount, String description, final BulkGraphOperation<T> operation) {
        return bulkGraphOperation(securityContext, iterator, commitCount, description, operation, true);
    }

    /**
     * Executes the given operation on all nodes in the given list.
     *
     * @param <T>
     * @param securityContext
     * @param iterator the iterator that provides the nodes to operate on
     * @param commitCount
     * @param description
     * @param operation the operation to execute
     * @param validation
     * @return the number of nodes processed
     */
    public static <T> long bulkGraphOperation(final SecurityContext securityContext, final Iterator<T> iterator,
            final long commitCount, String description, final BulkGraphOperation<T> operation, boolean validation) {

        final org.neo4j.helpers.Predicate<Long> condition = operation.getCondition();
        final App app = StructrApp.getInstance(securityContext);
        long objectCount = 0L;
        boolean active = true;

        while (active) {

            active = false;

            try (final Tx tx = app.tx()) {

                while (iterator.hasNext() && (condition == null || condition.accept(objectCount))) {

                    T node = iterator.next();
                    active = true;

                    try {

                        operation.handleGraphObject(securityContext, node);

                    } catch (Throwable t) {

                        operation.handleThrowable(securityContext, t, node);
                    }

                    // commit transaction after commitCount
                    if ((++objectCount % commitCount) == 0) {
                        break;
                    }
                }

                tx.success();

            } catch (Throwable t) {

                // bulk transaction failed, what to do?
                operation.handleTransactionFailure(securityContext, t);
            }

            if (description != null) {
                logger.log(Level.INFO, "{0}: {1} objects processed", new Object[] { description, objectCount });
            }
        }

        return objectCount;
    }

    /**
     * Executes the given transaction until the stop condition evaluates to
     * <b>true</b>.
     *
     * @param securityContext
     * @param commitCount the number of executions after which the transaction is committed
     * @param transaction the operation to execute
     * @param stopCondition
     * @throws FrameworkException
     */
    public static void bulkTransaction(final SecurityContext securityContext, final long commitCount,
            final StructrTransaction transaction, final Predicate<Long> stopCondition) throws FrameworkException {

        final App app = StructrApp.getInstance(securityContext);
        final AtomicLong objectCount = new AtomicLong(0L);

        while (!stopCondition.evaluate(securityContext, objectCount.get())) {

            try (final Tx tx = app.tx()) {

                long loopCount = 0;

                while (loopCount++ < commitCount && !stopCondition.evaluate(securityContext, objectCount.get())) {

                    transaction.execute();
                    objectCount.incrementAndGet();
                }

                tx.success();
            }
        }
    }

    public static String getNextUuid() {

        String uuid = null;

        do {

            uuid = uuidQueue.poll();

        } while (uuid == null);

        return uuid;
    }

    // create uuid producer that fills the queue
    static {

        Thread uuidProducer = new Thread(new Runnable() {

            @Override
            public void run() {

                // please do not stop :)
                while (true) {

                    try {
                        while (true) {

                            uuidQueue.put(StringUtils.replace(UUID.randomUUID().toString(), "-", ""));
                        }

                    } catch (Throwable t) {
                    }
                }
            }

        }, "UuidProducerThread");

        uuidProducer.setDaemon(true);
        uuidProducer.start();
    }
}