org.kie.kieora.backend.lucene.setups.BaseLuceneSetup.java Source code

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Here is the source code for org.kie.kieora.backend.lucene.setups.BaseLuceneSetup.java

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/*
 * Copyright 2012 JBoss Inc
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *       http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.kie.kieora.backend.lucene.setups;

import java.io.IOException;
import java.util.List;

import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.StringField;
import org.apache.lucene.index.AtomicReader;
import org.apache.lucene.index.AtomicReaderContext;
import org.apache.lucene.index.DocsEnum;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.TermsEnum;
import org.apache.lucene.search.DocIdSetIterator;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.util.BytesRef;
import org.kie.kieora.backend.lucene.LuceneSetup;

public abstract class BaseLuceneSetup implements LuceneSetup {

    @Override
    public void indexDocument(final String id, final Document doc) {
        try {
            deleteIfExists(id);
            writer().addDocument(doc);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public void deleteIfExists(final String... docIds) {
        final IndexSearcher searcher = nrtSearcher();
        try {
            final int[] answers = lookupDocIdByPK(searcher, docIds);
            for (final int docId : answers) {
                if (docId != -1) {
                    writer().tryDeleteDocument(searcher.getIndexReader(), docId);
                }
            }
        } catch (Exception ex) {
        } finally {
            nrtRelease(searcher);
        }
    }

    @Override
    public void rename(final String sourceId, final String targetId) {
        final IndexSearcher searcher = nrtSearcher();
        try {
            int docId = lookupDocIdByPK(searcher, sourceId)[0];
            final Document source = searcher.getIndexReader().document(docId);

            source.removeField("id");
            source.add(new StringField("id", targetId, Field.Store.YES));

            indexDocument(sourceId, source);
        } catch (IOException ex) {
        } finally {
            nrtRelease(searcher);
        }
    }

    protected int[] lookupDocIdByPK(final IndexSearcher searcher, final String... ids) throws IOException {
        final List<AtomicReaderContext> subReaders = searcher.getIndexReader().leaves();
        final TermsEnum[] termsEnums = new TermsEnum[subReaders.size()];
        final DocsEnum[] docsEnums = new DocsEnum[subReaders.size()];
        for (int subIDX = 0; subIDX < subReaders.size(); subIDX++) {
            termsEnums[subIDX] = subReaders.get(subIDX).reader().fields().terms("id").iterator(null);
        }

        int[] results = new int[ids.length];

        for (int i = 0; i < results.length; i++) {
            results[i] = -1;
        }

        for (int idx = 0; idx < ids.length; idx++) {
            int base = 0;
            final BytesRef id = new BytesRef(ids[idx]);
            for (int subIDX = 0; subIDX < subReaders.size(); subIDX++) {
                final AtomicReader sub = subReaders.get(subIDX).reader();
                final TermsEnum termsEnum = termsEnums[subIDX];
                if (termsEnum.seekExact(id, false)) {
                    final DocsEnum docs = docsEnums[subIDX] = termsEnum.docs(sub.getLiveDocs(), docsEnums[subIDX],
                            0);
                    if (docs != null) {
                        final int docID = docs.nextDoc();
                        if (docID != DocIdSetIterator.NO_MORE_DOCS) {
                            results[idx] = base + docID;
                            break;
                        }
                    }
                }
                base += sub.maxDoc();
            }
        }

        return results;
    }

    public abstract IndexWriter writer();

}