org.neo4j.index.impl.lucene.CommitContext.java Source code

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Here is the source code for org.neo4j.index.impl.lucene.CommitContext.java

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/**
 * Copyright (c) 2002-2014 "Neo Technology,"
 * Network Engine for Objects in Lund AB [http://neotechnology.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 <http://www.gnu.org/licenses/>.
 */
package org.neo4j.index.impl.lucene;

import java.io.Closeable;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

import org.apache.lucene.document.Document;
import org.apache.lucene.index.IndexWriter;

/**
 * This presents a context for each {@link LuceneCommand} when they are
 * committing its data.
 */
class CommitContext implements Closeable {
    final LuceneDataSource dataSource;
    final IndexIdentifier identifier;
    final IndexType indexType;
    final Map<Long, DocumentContext> documents = new HashMap<>();
    final boolean recovery;

    IndexReference searcher;
    IndexWriter writer;

    CommitContext(LuceneDataSource dataSource, IndexIdentifier identifier, IndexType indexType,
            boolean isRecovery) {
        this.dataSource = dataSource;
        this.identifier = identifier;
        this.indexType = indexType;
        this.recovery = isRecovery;
    }

    void ensureWriterInstantiated() {
        if (searcher == null) {
            searcher = dataSource.getIndexSearcher(identifier);
            writer = searcher.getWriter();
        }
    }

    DocumentContext getDocument(Object entityId, boolean allowCreate) {
        long id = entityId instanceof Long ? (Long) entityId : ((RelationshipId) entityId).id;
        DocumentContext context = documents.get(id);
        if (context != null) {
            return context;
        }

        Document document = LuceneDataSource.findDocument(indexType, searcher.getSearcher(), id);
        if (document != null) {
            context = new DocumentContext(document, true, id);
            documents.put(id, context);
        } else if (allowCreate) {
            context = new DocumentContext(IndexType.newDocument(entityId), false, id);
            documents.put(id, context);
        }
        return context;
    }

    private void applyDocuments(IndexWriter writer, IndexType type, Map<Long, DocumentContext> documents)
            throws IOException {
        for (Map.Entry<Long, DocumentContext> entry : documents.entrySet()) {
            DocumentContext context = entry.getValue();
            if (context.exists) {
                if (LuceneDataSource.documentIsEmpty(context.document)) {
                    writer.deleteDocuments(type.idTerm(context.entityId));
                } else {
                    writer.updateDocument(type.idTerm(context.entityId), context.document);
                }
            } else {
                writer.addDocument(context.document);
            }
        }
    }

    @Override
    public void close() throws IOException {
        applyDocuments(writer, indexType, documents);
        if (writer != null) {
            dataSource.invalidateIndexSearcher(identifier);
        }
        if (searcher != null) {
            searcher.close();
        }
    }

    static class DocumentContext {
        final Document document;
        final boolean exists;
        final long entityId;

        DocumentContext(Document document, boolean exists, long entityId) {
            this.document = document;
            this.exists = exists;
            this.entityId = entityId;
        }
    }
}