Java tutorial
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See the License for the * specific language governing permissions and limitations * under the License. */ package org.elasticsearch.index.engine; import org.apache.lucene.index.BinaryDocValues; import org.apache.lucene.index.DocValuesType; import org.apache.lucene.index.FieldInfo; import org.apache.lucene.index.FieldInfos; import org.apache.lucene.index.Fields; import org.apache.lucene.index.IndexOptions; import org.apache.lucene.index.LeafMetaData; import org.apache.lucene.index.LeafReader; import org.apache.lucene.index.NumericDocValues; import org.apache.lucene.index.PointValues; import org.apache.lucene.index.SortedDocValues; import org.apache.lucene.index.SortedNumericDocValues; import org.apache.lucene.index.SortedSetDocValues; import org.apache.lucene.index.StoredFieldVisitor; import org.apache.lucene.index.Terms; import org.apache.lucene.util.Bits; import org.apache.lucene.util.BytesRef; import org.elasticsearch.Version; import org.elasticsearch.index.mapper.IdFieldMapper; import org.elasticsearch.index.mapper.RoutingFieldMapper; import org.elasticsearch.index.mapper.SourceFieldMapper; import org.elasticsearch.index.mapper.Uid; import org.elasticsearch.index.translog.Translog; import java.io.IOException; import java.nio.charset.StandardCharsets; import java.util.Collections; /** * Internal class that mocks a single doc read from the transaction log as a leaf reader. */ final class TranslogLeafReader extends LeafReader { private final Translog.Index operation; private static final FieldInfo FAKE_SOURCE_FIELD = new FieldInfo(SourceFieldMapper.NAME, 1, false, false, false, IndexOptions.NONE, DocValuesType.NONE, -1, Collections.emptyMap(), 0, 0, false); private static final FieldInfo FAKE_ROUTING_FIELD = new FieldInfo(RoutingFieldMapper.NAME, 2, false, false, false, IndexOptions.NONE, DocValuesType.NONE, -1, Collections.emptyMap(), 0, 0, false); private static final FieldInfo FAKE_ID_FIELD = new FieldInfo(IdFieldMapper.NAME, 3, false, false, false, IndexOptions.NONE, DocValuesType.NONE, -1, Collections.emptyMap(), 0, 0, false); private final Version indexVersionCreated; TranslogLeafReader(Translog.Index operation, Version indexVersionCreated) { this.operation = operation; this.indexVersionCreated = indexVersionCreated; } @Override public CacheHelper getCoreCacheHelper() { throw new UnsupportedOperationException(); } @Override public Terms terms(String field) { throw new UnsupportedOperationException(); } @Override public NumericDocValues getNumericDocValues(String field) { throw new UnsupportedOperationException(); } @Override public BinaryDocValues getBinaryDocValues(String field) { throw new UnsupportedOperationException(); } @Override public SortedDocValues getSortedDocValues(String field) { throw new UnsupportedOperationException(); } @Override public SortedNumericDocValues getSortedNumericDocValues(String field) { throw new UnsupportedOperationException(); } @Override public SortedSetDocValues getSortedSetDocValues(String field) { throw new UnsupportedOperationException(); } @Override public NumericDocValues getNormValues(String field) { throw new UnsupportedOperationException(); } @Override public FieldInfos getFieldInfos() { throw new UnsupportedOperationException(); } @Override public Bits getLiveDocs() { throw new UnsupportedOperationException(); } @Override public PointValues getPointValues(String field) { throw new UnsupportedOperationException(); } @Override public void checkIntegrity() { } @Override public LeafMetaData getMetaData() { throw new UnsupportedOperationException(); } @Override public Fields getTermVectors(int docID) { throw new UnsupportedOperationException(); } @Override public int numDocs() { return 1; } @Override public int maxDoc() { return 1; } @Override public void document(int docID, StoredFieldVisitor visitor) throws IOException { if (docID != 0) { throw new IllegalArgumentException("no such doc ID " + docID); } if (visitor.needsField(FAKE_SOURCE_FIELD) == StoredFieldVisitor.Status.YES) { assert operation.source().toBytesRef().offset == 0; assert operation.source().toBytesRef().length == operation.source().toBytesRef().bytes.length; visitor.binaryField(FAKE_SOURCE_FIELD, operation.source().toBytesRef().bytes); } if (operation.routing() != null && visitor.needsField(FAKE_ROUTING_FIELD) == StoredFieldVisitor.Status.YES) { visitor.stringField(FAKE_ROUTING_FIELD, operation.routing().getBytes(StandardCharsets.UTF_8)); } if (visitor.needsField(FAKE_ID_FIELD) == StoredFieldVisitor.Status.YES) { final byte[] id; if (indexVersionCreated.onOrAfter(Version.V_6_0_0)) { BytesRef bytesRef = Uid.encodeId(operation.id()); id = new byte[bytesRef.length]; System.arraycopy(bytesRef.bytes, bytesRef.offset, id, 0, bytesRef.length); } else { // TODO this can go away in 7.0 after backport id = operation.id().getBytes(StandardCharsets.UTF_8); } visitor.stringField(FAKE_ID_FIELD, id); } } @Override protected void doClose() { } @Override public CacheHelper getReaderCacheHelper() { throw new UnsupportedOperationException(); } }