package org.apache.lucene.codecs.perfield;
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.
*/
import java.io.Closeable;
import java.io.IOException;
import java.util.HashMap;
import java.util.IdentityHashMap;
import java.util.Map;
import java.util.ServiceLoader; // javadocs
import java.util.TreeMap;
import org.apache.lucene.codecs.PostingsFormat;
import org.apache.lucene.codecs.DocValuesConsumer;
import org.apache.lucene.codecs.DocValuesProducer;
import org.apache.lucene.codecs.DocValuesFormat;
import org.apache.lucene.index.BinaryDocValues;
import org.apache.lucene.index.FieldInfo;
import org.apache.lucene.index.NumericDocValues;
import org.apache.lucene.index.SegmentReadState;
import org.apache.lucene.index.SegmentWriteState;
import org.apache.lucene.index.SortedDocValues;
import org.apache.lucene.index.SortedSetDocValues;
import org.apache.lucene.util.BytesRef;
import org.apache.lucene.util.IOUtils;
/**
* Enables per field docvalues support.
* <p>
* Note, when extending this class, the name ({@link #getName}) is
* written into the index. In order for the field to be read, the
* name must resolve to your implementation via {@link #forName(String)}.
* This method uses Java's
* {@link ServiceLoader Service Provider Interface} to resolve format names.
* <p>
* Files written by each docvalues format have an additional suffix containing the
* format name. For example, in a per-field configuration instead of <tt>_1.dat</tt>
* filenames would look like <tt>_1_Lucene40_0.dat</tt>.
* @see ServiceLoader
* @lucene.experimental
*/
public abstract class PerFieldDocValuesFormat extends DocValuesFormat {
/** Name of this {@link PostingsFormat}. */
public static final String PER_FIELD_NAME = "PerFieldDV40";
/** {@link FieldInfo} attribute name used to store the
* format name for each field. */
public static final String PER_FIELD_FORMAT_KEY = PerFieldDocValuesFormat.class.getSimpleName() + ".format";
/** {@link FieldInfo} attribute name used to store the
* segment suffix name for each field. */
public static final String PER_FIELD_SUFFIX_KEY = PerFieldDocValuesFormat.class.getSimpleName() + ".suffix";
/** Sole constructor. */
public PerFieldDocValuesFormat() {
super(PER_FIELD_NAME);
}
@Override
public final DocValuesConsumer fieldsConsumer(SegmentWriteState state)
throws IOException {
return new FieldsWriter(state);
}
static class ConsumerAndSuffix implements Closeable {
DocValuesConsumer consumer;
int suffix;
@Override
public void close() throws IOException {
consumer.close();
}
}
private class FieldsWriter extends DocValuesConsumer {
private final Map<DocValuesFormat,ConsumerAndSuffix> formats = new HashMap<DocValuesFormat,ConsumerAndSuffix>();
private final Map<String,Integer> suffixes = new HashMap<String,Integer>();
private final SegmentWriteState segmentWriteState;
public FieldsWriter(SegmentWriteState state) {
segmentWriteState = state;
}
@Override
public void addNumericField(FieldInfo field, Iterable<Number> values) throws IOException {
getInstance(field).addNumericField(field, values);
}
@Override
public void addBinaryField(FieldInfo field, Iterable<BytesRef> values) throws IOException {
getInstance(field).addBinaryField(field, values);
}
@Override
public void addSortedField(FieldInfo field, Iterable<BytesRef> values, Iterable<Number> docToOrd) throws IOException {
getInstance(field).addSortedField(field, values, docToOrd);
}
@Override
public void addSortedSetField(FieldInfo field, Iterable<BytesRef> values, Iterable<Number> docToOrdCount, Iterable<Number> ords) throws IOException {
getInstance(field).addSortedSetField(field, values, docToOrdCount, ords);
}
private DocValuesConsumer getInstance(FieldInfo field) throws IOException {
final DocValuesFormat format = getDocValuesFormatForField(field.name);
if (format == null) {
throw new IllegalStateException("invalid null DocValuesFormat for field=\"" + field.name + "\"");
}
final String formatName = format.getName();
String previousValue = field.putAttribute(PER_FIELD_FORMAT_KEY, formatName);
assert previousValue == null: "formatName=" + formatName + " prevValue=" + previousValue;
Integer suffix;
ConsumerAndSuffix consumer = formats.get(format);
if (consumer == null) {
// First time we are seeing this format; create a new instance
// bump the suffix
suffix = suffixes.get(formatName);
if (suffix == null) {
suffix = 0;
} else {
suffix = suffix + 1;
}
suffixes.put(formatName, suffix);
final String segmentSuffix = getFullSegmentSuffix(field.name,
segmentWriteState.segmentSuffix,
getSuffix(formatName, Integer.toString(suffix)));
consumer = new ConsumerAndSuffix();
consumer.consumer = format.fieldsConsumer(new SegmentWriteState(segmentWriteState, segmentSuffix));
consumer.suffix = suffix;
formats.put(format, consumer);
} else {
// we've already seen this format, so just grab its suffix
assert suffixes.containsKey(formatName);
suffix = consumer.suffix;
}
previousValue = field.putAttribute(PER_FIELD_SUFFIX_KEY, Integer.toString(suffix));
assert previousValue == null;
// TODO: we should only provide the "slice" of FIS
// that this PF actually sees ...
return consumer.consumer;
}
@Override
public void close() throws IOException {
// Close all subs
IOUtils.close(formats.values());
}
}
static String getSuffix(String formatName, String suffix) {
return formatName + "_" + suffix;
}
static String getFullSegmentSuffix(String fieldName, String outerSegmentSuffix, String segmentSuffix) {
if (outerSegmentSuffix.length() == 0) {
return segmentSuffix;
} else {
// TODO: support embedding; I think it should work but
// we need a test confirm to confirm
// return outerSegmentSuffix + "_" + segmentSuffix;
throw new IllegalStateException("cannot embed PerFieldPostingsFormat inside itself (field \"" + fieldName + "\" returned PerFieldPostingsFormat)");
}
}
private class FieldsReader extends DocValuesProducer {
private final Map<String,DocValuesProducer> fields = new TreeMap<String,DocValuesProducer>();
private final Map<String,DocValuesProducer> formats = new HashMap<String,DocValuesProducer>();
public FieldsReader(final SegmentReadState readState) throws IOException {
// Read _X.per and init each format:
boolean success = false;
try {
// Read field name -> format name
for (FieldInfo fi : readState.fieldInfos) {
if (fi.hasDocValues()) {
final String fieldName = fi.name;
final String formatName = fi.getAttribute(PER_FIELD_FORMAT_KEY);
if (formatName != null) {
// null formatName means the field is in fieldInfos, but has no docvalues!
final String suffix = fi.getAttribute(PER_FIELD_SUFFIX_KEY);
assert suffix != null;
DocValuesFormat format = DocValuesFormat.forName(formatName);
String segmentSuffix = getSuffix(formatName, suffix);
if (!formats.containsKey(segmentSuffix)) {
formats.put(segmentSuffix, format.fieldsProducer(new SegmentReadState(readState, segmentSuffix)));
}
fields.put(fieldName, formats.get(segmentSuffix));
}
}
}
success = true;
} finally {
if (!success) {
IOUtils.closeWhileHandlingException(formats.values());
}
}
}
private FieldsReader(FieldsReader other) {
Map<DocValuesProducer,DocValuesProducer> oldToNew = new IdentityHashMap<DocValuesProducer,DocValuesProducer>();
// First clone all formats
for(Map.Entry<String,DocValuesProducer> ent : other.formats.entrySet()) {
DocValuesProducer values = ent.getValue();
formats.put(ent.getKey(), values);
oldToNew.put(ent.getValue(), values);
}
// Then rebuild fields:
for(Map.Entry<String,DocValuesProducer> ent : other.fields.entrySet()) {
DocValuesProducer producer = oldToNew.get(ent.getValue());
assert producer != null;
fields.put(ent.getKey(), producer);
}
}
@Override
public NumericDocValues getNumeric(FieldInfo field) throws IOException {
DocValuesProducer producer = fields.get(field.name);
return producer == null ? null : producer.getNumeric(field);
}
@Override
public BinaryDocValues getBinary(FieldInfo field) throws IOException {
DocValuesProducer producer = fields.get(field.name);
return producer == null ? null : producer.getBinary(field);
}
@Override
public SortedDocValues getSorted(FieldInfo field) throws IOException {
DocValuesProducer producer = fields.get(field.name);
return producer == null ? null : producer.getSorted(field);
}
@Override
public SortedSetDocValues getSortedSet(FieldInfo field) throws IOException {
DocValuesProducer producer = fields.get(field.name);
return producer == null ? null : producer.getSortedSet(field);
}
@Override
public void close() throws IOException {
IOUtils.close(formats.values());
}
@Override
public DocValuesProducer clone() {
return new FieldsReader(this);
}
}
@Override
public final DocValuesProducer fieldsProducer(SegmentReadState state) throws IOException {
return new FieldsReader(state);
}
/**
* Returns the doc values format that should be used for writing
* new segments of <code>field</code>.
* <p>
* The field to format mapping is written to the index, so
* this method is only invoked when writing, not when reading. */
public abstract DocValuesFormat getDocValuesFormatForField(String field);
}