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/*
* Copyright (c) 2015, 2024, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package com.sun.marlin;
import static com.sun.marlin.ArrayCacheConst.ARRAY_SIZES;
import static com.sun.marlin.ArrayCacheConst.BUCKETS;
import static com.sun.marlin.ArrayCacheConst.MAX_ARRAY_SIZE;
import static com.sun.marlin.MarlinConst.DO_STATS;
import static com.sun.marlin.MarlinConst.DO_CHECKS;
import static com.sun.marlin.MarlinConst.DO_CLEAN_DIRTY;
import static com.sun.marlin.MarlinConst.DO_LOG_WIDEN_ARRAY;
import static com.sun.marlin.MarlinConst.DO_LOG_OVERSIZE;
import static com.sun.marlin.MarlinUtils.logInfo;
import static com.sun.marlin.MarlinUtils.logException;
import java.lang.ref.WeakReference;
import java.util.Arrays;
import com.sun.marlin.ArrayCacheConst.BucketStats;
import com.sun.marlin.ArrayCacheConst.CacheStats;
/*
* Note that the ArrayCache[Byte/Double/Int] files are nearly identical except
* for their array type [byte/double/int] and class name differences.
* ArrayCache[Byte/Double/Int] class deals with dirty arrays.
*/
public final class ArrayCacheByte {
/* members */
private final int bucketCapacity;
private WeakReference refBuckets = null;
final CacheStats stats;
ArrayCacheByte(final int bucketCapacity) {
this.bucketCapacity = bucketCapacity;
this.stats = (DO_STATS) ?
new CacheStats("ArrayCacheByte(Dirty)") : null;
}
Bucket getCacheBucket(final int length) {
final int bucket = ArrayCacheConst.getBucket(length);
return getBuckets()[bucket];
}
private Bucket[] getBuckets() {
// resolve reference:
Bucket[] buckets = (refBuckets != null) ? refBuckets.get() : null;
// create a new buckets ?
if (buckets == null) {
buckets = new Bucket[BUCKETS];
for (int i = 0; i < BUCKETS; i++) {
buckets[i] = new Bucket(ARRAY_SIZES[i], bucketCapacity,
(DO_STATS) ? stats.bucketStats[i] : null);
}
// update weak reference:
refBuckets = new WeakReference<>(buckets);
}
return buckets;
}
Reference createRef(final int initialSize) {
return new Reference(this, initialSize);
}
static final class Reference {
// initial array reference (direct access)
final byte[] initial;
private final ArrayCacheByte cache;
Reference(final ArrayCacheByte cache, final int initialSize) {
this.cache = cache;
this.initial = createArray(initialSize);
if (DO_STATS) {
cache.stats.totalInitial += initialSize;
}
}
byte[] getArray(final int length) {
if (length <= MAX_ARRAY_SIZE) {
return cache.getCacheBucket(length).getArray();
}
if (DO_STATS) {
cache.stats.oversize++;
}
if (DO_LOG_OVERSIZE) {
logInfo("ArrayCacheByte(Dirty): "
+ "getArray[oversize]: length=\t" + length);
}
return createArray(length);
}
byte[] widenArray(final byte[] array, final int usedSize,
final int needSize)
{
final int length = array.length;
if (DO_CHECKS && length >= needSize) {
return array;
}
if (DO_STATS) {
cache.stats.resize++;
}
// maybe change bucket:
// ensure getNewSize() > newSize:
final byte[] res = getArray(ArrayCacheConst.getNewSize(usedSize, needSize));
// use wrapper to ensure proper copy:
System.arraycopy(array, 0, res, 0, usedSize); // copy only used elements
// maybe return current array:
putArray(array, 0, usedSize); // ensure array is cleared
if (DO_LOG_WIDEN_ARRAY) {
logInfo("ArrayCacheByte(Dirty): "
+ "widenArray[" + res.length
+ "]: usedSize=\t" + usedSize + "\tlength=\t" + length
+ "\tneeded length=\t" + needSize);
}
return res;
}
boolean doCleanRef(final byte[] array) {
return DO_CLEAN_DIRTY || (array != initial);
}
byte[] putArray(final byte[] array)
{
// dirty array helper:
return putArray(array, 0, array.length);
}
byte[] putArray(final byte[] array, final int fromIndex,
final int toIndex)
{
if (array.length <= MAX_ARRAY_SIZE) {
if (DO_CLEAN_DIRTY && (toIndex != 0)) {
// clean-up array of dirty part[fromIndex; toIndex[
fill(array, fromIndex, toIndex, (byte)0);
}
// ensure to never store initial arrays in cache:
if (array != initial) {
cache.getCacheBucket(array.length).putArray(array);
}
}
return initial;
}
}
static final class Bucket {
private int tail = 0;
private final int arraySize;
private final byte[][] arrays;
private final BucketStats stats;
Bucket(final int arraySize,
final int capacity, final BucketStats stats)
{
this.arraySize = arraySize;
this.stats = stats;
this.arrays = new byte[capacity][];
}
byte[] getArray() {
if (DO_STATS) {
stats.getOp++;
}
// use cache:
if (tail != 0) {
final byte[] array = arrays[--tail];
arrays[tail] = null;
return array;
}
if (DO_STATS) {
stats.createOp++;
}
return createArray(arraySize);
}
void putArray(final byte[] array)
{
if (DO_CHECKS && (array.length != arraySize)) {
logInfo("ArrayCacheByte(Dirty): "
+ "bad length = " + array.length);
return;
}
if (DO_STATS) {
stats.returnOp++;
}
// fill cache:
if (arrays.length > tail) {
arrays[tail++] = array;
if (DO_STATS) {
stats.updateMaxSize(tail);
}
} else if (DO_CHECKS) {
logInfo("ArrayCacheByte(Dirty): "
+ "array capacity exceeded !");
}
}
}
static byte[] createArray(final int length) {
return new byte[length];
}
static void fill(final byte[] array, final int fromIndex,
final int toIndex, final byte value)
{
// clear array data:
Arrays.fill(array, fromIndex, toIndex, value);
if (DO_CHECKS) {
check(array, fromIndex, toIndex, value);
}
}
static void check(final byte[] array, final int fromIndex,
final int toIndex, final byte value)
{
if (DO_CHECKS) {
// check zero on full array:
for (int i = 0; i < array.length; i++) {
if (array[i] != value) {
logException("Invalid value at: " + i + " = " + array[i]
+ " from: " + fromIndex + " to: " + toIndex + "\n"
+ Arrays.toString(array), new Throwable());
// ensure array is correctly filled:
Arrays.fill(array, value);
return;
}
}
}
}
}