+++ /dev/null
-package org.apache.lucene.util;
-
-/**
- * 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.lang.reflect.*;
-import java.text.DecimalFormat;
-import java.util.*;
-
-/**
- * Estimates the size of a given Object using a given MemoryModel for primitive
- * size information.
- *
- * Resource Usage:
- *
- * Internally uses a Map to temporally hold a reference to every
- * object seen.
- *
- * If checkInterned, all Strings checked will be interned, but those
- * that were not already interned will be released for GC when the
- * estimate is complete.
- *
- * @lucene.internal
- */
-public final class RamUsageEstimator {
-
- public final static int NUM_BYTES_SHORT = 2;
- public final static int NUM_BYTES_INT = 4;
- public final static int NUM_BYTES_LONG = 8;
- public final static int NUM_BYTES_FLOAT = 4;
- public final static int NUM_BYTES_DOUBLE = 8;
- public final static int NUM_BYTES_CHAR = 2;
- public final static int NUM_BYTES_OBJECT_HEADER = 8;
- public final static int NUM_BYTES_OBJECT_REF = Constants.JRE_IS_64BIT ? 8 : 4;
- public final static int NUM_BYTES_ARRAY_HEADER = NUM_BYTES_OBJECT_HEADER + NUM_BYTES_INT + NUM_BYTES_OBJECT_REF;
-
- private MemoryModel memoryModel;
-
- private final Map<Object,Object> seen;
-
- private int refSize;
- private int arraySize;
- private int classSize;
-
- private boolean checkInterned;
-
- /**
- * Constructs this object with an AverageGuessMemoryModel and
- * checkInterned = true.
- */
- public RamUsageEstimator() {
- this(new AverageGuessMemoryModel());
- }
-
- /**
- * @param checkInterned check if Strings are interned and don't add to size
- * if they are. Defaults to true but if you know the objects you are checking
- * won't likely contain many interned Strings, it will be faster to turn off
- * intern checking.
- */
- public RamUsageEstimator(boolean checkInterned) {
- this(new AverageGuessMemoryModel(), checkInterned);
- }
-
- /**
- * @param memoryModel MemoryModel to use for primitive object sizes.
- */
- public RamUsageEstimator(MemoryModel memoryModel) {
- this(memoryModel, true);
- }
-
- /**
- * @param memoryModel MemoryModel to use for primitive object sizes.
- * @param checkInterned check if Strings are interned and don't add to size
- * if they are. Defaults to true but if you know the objects you are checking
- * won't likely contain many interned Strings, it will be faster to turn off
- * intern checking.
- */
- public RamUsageEstimator(MemoryModel memoryModel, boolean checkInterned) {
- this.memoryModel = memoryModel;
- this.checkInterned = checkInterned;
- // Use Map rather than Set so that we can use an IdentityHashMap - not
- // seeing an IdentityHashSet
- seen = new IdentityHashMap<Object,Object>(64);
- this.refSize = memoryModel.getReferenceSize();
- this.arraySize = memoryModel.getArraySize();
- this.classSize = memoryModel.getClassSize();
- }
-
- public long estimateRamUsage(Object obj) {
- long size = size(obj);
- seen.clear();
- return size;
- }
-
- private long size(Object obj) {
- if (obj == null) {
- return 0;
- }
- // interned not part of this object
- if (checkInterned && obj instanceof String
- && obj == ((String) obj).intern()) { // interned string will be eligible
- // for GC on
- // estimateRamUsage(Object) return
- return 0;
- }
-
- // skip if we have seen before
- if (seen.containsKey(obj)) {
- return 0;
- }
-
- // add to seen
- seen.put(obj, null);
-
- Class<?> clazz = obj.getClass();
- if (clazz.isArray()) {
- return sizeOfArray(obj);
- }
-
- long size = 0;
-
- // walk type hierarchy
- while (clazz != null) {
- Field[] fields = clazz.getDeclaredFields();
- for (int i = 0; i < fields.length; i++) {
- if (Modifier.isStatic(fields[i].getModifiers())) {
- continue;
- }
-
- if (fields[i].getType().isPrimitive()) {
- size += memoryModel.getPrimitiveSize(fields[i].getType());
- } else {
- size += refSize;
- fields[i].setAccessible(true);
- try {
- Object value = fields[i].get(obj);
- if (value != null) {
- size += size(value);
- }
- } catch (IllegalAccessException ex) {
- // ignore for now?
- }
- }
-
- }
- clazz = clazz.getSuperclass();
- }
- size += classSize;
- return size;
- }
-
- private long sizeOfArray(Object obj) {
- int len = Array.getLength(obj);
- if (len == 0) {
- return 0;
- }
- long size = arraySize;
- Class<?> arrayElementClazz = obj.getClass().getComponentType();
- if (arrayElementClazz.isPrimitive()) {
- size += len * memoryModel.getPrimitiveSize(arrayElementClazz);
- } else {
- for (int i = 0; i < len; i++) {
- size += refSize + size(Array.get(obj, i));
- }
- }
-
- return size;
- }
-
- private static final long ONE_KB = 1024;
- private static final long ONE_MB = ONE_KB * ONE_KB;
- private static final long ONE_GB = ONE_KB * ONE_MB;
-
- /**
- * Return good default units based on byte size.
- */
- public static String humanReadableUnits(long bytes, DecimalFormat df) {
- String newSizeAndUnits;
-
- if (bytes / ONE_GB > 0) {
- newSizeAndUnits = String.valueOf(df.format((float) bytes / ONE_GB))
- + " GB";
- } else if (bytes / ONE_MB > 0) {
- newSizeAndUnits = String.valueOf(df.format((float) bytes / ONE_MB))
- + " MB";
- } else if (bytes / ONE_KB > 0) {
- newSizeAndUnits = String.valueOf(df.format((float) bytes / ONE_KB))
- + " KB";
- } else {
- newSizeAndUnits = String.valueOf(bytes) + " bytes";
- }
-
- return newSizeAndUnits;
- }
-}
fnp / pylucene.git / blobdiff