+++ /dev/null
-package org.apache.lucene.index;
-
-/**
- * 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.IOException;
-import java.util.concurrent.atomic.AtomicInteger;
-
-import org.apache.lucene.store.IndexInput;
-import org.apache.lucene.store.IndexOutput;
-
-/**
- * Byte[] referencing is used because a new norm object needs
- * to be created for each clone, and the byte array is all
- * that is needed for sharing between cloned readers. The
- * current norm referencing is for sharing between readers
- * whereas the byte[] referencing is for copy on write which
- * is independent of reader references (i.e. incRef, decRef).
- */
-
-final class SegmentNorms implements Cloneable {
-
- /** norms header placeholder */
- static final byte[] NORMS_HEADER = new byte[]{'N','R','M',-1};
-
- int refCount = 1;
-
- // If this instance is a clone, the originalNorm
- // references the Norm that has a real open IndexInput:
- private SegmentNorms origNorm;
-
- private IndexInput in;
- private long normSeek;
-
- // null until bytes is set
- private AtomicInteger bytesRef;
- private byte[] bytes;
- private int number;
-
- boolean dirty;
- boolean rollbackDirty;
-
- private final SegmentReader owner;
-
- public SegmentNorms(IndexInput in, int number, long normSeek, SegmentReader owner) {
- this.in = in;
- this.number = number;
- this.normSeek = normSeek;
- this.owner = owner;
- }
-
- public synchronized void incRef() {
- assert refCount > 0 && (origNorm == null || origNorm.refCount > 0);
- refCount++;
- }
-
- private void closeInput() throws IOException {
- if (in != null) {
- if (in != owner.singleNormStream) {
- // It's private to us -- just close it
- in.close();
- } else {
- // We are sharing this with others -- decRef and
- // maybe close the shared norm stream
- if (owner.singleNormRef.decrementAndGet() == 0) {
- owner.singleNormStream.close();
- owner.singleNormStream = null;
- }
- }
-
- in = null;
- }
- }
-
- public synchronized void decRef() throws IOException {
- assert refCount > 0 && (origNorm == null || origNorm.refCount > 0);
-
- if (--refCount == 0) {
- if (origNorm != null) {
- origNorm.decRef();
- origNorm = null;
- } else {
- closeInput();
- }
-
- if (bytes != null) {
- assert bytesRef != null;
- bytesRef.decrementAndGet();
- bytes = null;
- bytesRef = null;
- } else {
- assert bytesRef == null;
- }
- }
- }
-
- // Load bytes but do not cache them if they were not
- // already cached
- public synchronized void bytes(byte[] bytesOut, int offset, int len) throws IOException {
- assert refCount > 0 && (origNorm == null || origNorm.refCount > 0);
- if (bytes != null) {
- // Already cached -- copy from cache:
- assert len <= owner.maxDoc();
- System.arraycopy(bytes, 0, bytesOut, offset, len);
- } else {
- // Not cached
- if (origNorm != null) {
- // Ask origNorm to load
- origNorm.bytes(bytesOut, offset, len);
- } else {
- // We are orig -- read ourselves from disk:
- synchronized(in) {
- in.seek(normSeek);
- in.readBytes(bytesOut, offset, len, false);
- }
- }
- }
- }
-
- // Load & cache full bytes array. Returns bytes.
- public synchronized byte[] bytes() throws IOException {
- assert refCount > 0 && (origNorm == null || origNorm.refCount > 0);
- if (bytes == null) { // value not yet read
- assert bytesRef == null;
- if (origNorm != null) {
- // Ask origNorm to load so that for a series of
- // reopened readers we share a single read-only
- // byte[]
- bytes = origNorm.bytes();
- bytesRef = origNorm.bytesRef;
- bytesRef.incrementAndGet();
-
- // Once we've loaded the bytes we no longer need
- // origNorm:
- origNorm.decRef();
- origNorm = null;
-
- } else {
- // We are the origNorm, so load the bytes for real
- // ourself:
- final int count = owner.maxDoc();
- bytes = new byte[count];
-
- // Since we are orig, in must not be null
- assert in != null;
-
- // Read from disk.
- synchronized(in) {
- in.seek(normSeek);
- in.readBytes(bytes, 0, count, false);
- }
-
- bytesRef = new AtomicInteger(1);
- closeInput();
- }
- }
-
- return bytes;
- }
-
- // Only for testing
- AtomicInteger bytesRef() {
- return bytesRef;
- }
-
- // Called if we intend to change a norm value. We make a
- // private copy of bytes if it's shared with others:
- public synchronized byte[] copyOnWrite() throws IOException {
- assert refCount > 0 && (origNorm == null || origNorm.refCount > 0);
- bytes();
- assert bytes != null;
- assert bytesRef != null;
- if (bytesRef.get() > 1) {
- // I cannot be the origNorm for another norm
- // instance if I'm being changed. Ie, only the
- // "head Norm" can be changed:
- assert refCount == 1;
- final AtomicInteger oldRef = bytesRef;
- bytes = owner.cloneNormBytes(bytes);
- bytesRef = new AtomicInteger(1);
- oldRef.decrementAndGet();
- }
- dirty = true;
- return bytes;
- }
-
- // Returns a copy of this Norm instance that shares
- // IndexInput & bytes with the original one
- @Override
- public synchronized Object clone() {
- assert refCount > 0 && (origNorm == null || origNorm.refCount > 0);
-
- SegmentNorms clone;
- try {
- clone = (SegmentNorms) super.clone();
- } catch (CloneNotSupportedException cnse) {
- // Cannot happen
- throw new RuntimeException("unexpected CloneNotSupportedException", cnse);
- }
- clone.refCount = 1;
-
- if (bytes != null) {
- assert bytesRef != null;
- assert origNorm == null;
-
- // Clone holds a reference to my bytes:
- clone.bytesRef.incrementAndGet();
- } else {
- assert bytesRef == null;
- if (origNorm == null) {
- // I become the origNorm for the clone:
- clone.origNorm = this;
- }
- clone.origNorm.incRef();
- }
-
- // Only the origNorm will actually readBytes from in:
- clone.in = null;
-
- return clone;
- }
-
- // Flush all pending changes to the next generation
- // separate norms file.
- public void reWrite(SegmentInfo si) throws IOException {
- assert refCount > 0 && (origNorm == null || origNorm.refCount > 0): "refCount=" + refCount + " origNorm=" + origNorm;
-
- // NOTE: norms are re-written in regular directory, not cfs
- si.advanceNormGen(this.number);
- final String normFileName = si.getNormFileName(this.number);
- IndexOutput out = owner.directory().createOutput(normFileName);
- boolean success = false;
- try {
- try {
- out.writeBytes(SegmentNorms.NORMS_HEADER, 0, SegmentNorms.NORMS_HEADER.length);
- out.writeBytes(bytes, owner.maxDoc());
- } finally {
- out.close();
- }
- success = true;
- } finally {
- if (!success) {
- try {
- owner.directory().deleteFile(normFileName);
- } catch (Throwable t) {
- // suppress this so we keep throwing the
- // original exception
- }
- }
- }
- this.dirty = false;
- }
-}
fnp / pylucene.git / blobdiff