| /* |
| * 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. |
| */ |
| package org.apache.lucene.codecs; |
| |
| import java.io.Closeable; |
| import java.io.IOException; |
| |
| import org.apache.lucene.index.FieldInfo; |
| import org.apache.lucene.index.NumericDocValues; |
| import org.apache.lucene.util.Accountable; |
| |
| |
| /** Abstract API that produces field normalization values |
| * |
| * @lucene.experimental |
| */ |
| public abstract class NormsProducer implements Closeable, Accountable { |
| |
| /** Sole constructor. (For invocation by subclass |
| * constructors, typically implicit.) */ |
| protected NormsProducer() {} |
| |
| /** Returns {@link NumericDocValues} for this field. |
| * The returned instance need not be thread-safe: it will only be |
| * used by a single thread. */ |
| public abstract NumericDocValues getNorms(FieldInfo field) throws IOException; |
| |
| /** |
| * Checks consistency of this producer |
| * <p> |
| * Note that this may be costly in terms of I/O, e.g. |
| * may involve computing a checksum value against large data files. |
| * @lucene.internal |
| */ |
| public abstract void checkIntegrity() throws IOException; |
| |
| /** |
| * Returns an instance optimized for merging. This instance may only be used |
| * from the thread that acquires it. |
| * <p> |
| * The default implementation returns {@code this} */ |
| public NormsProducer getMergeInstance() { |
| return this; |
| } |
| } |