| /** |
| * 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.hadoop.hdfs.util; |
| |
| import com.google.common.base.Preconditions; |
| import org.apache.commons.lang3.ArrayUtils; |
| |
| import java.util.Arrays; |
| |
| /** |
| * Counters for an enum type. |
| * |
| * For example, suppose there is an enum type |
| * <pre> |
| * enum Fruit { APPLE, ORANGE, GRAPE } |
| * </pre> |
| * An {@link EnumCounters} object can be created for counting the numbers of |
| * APPLE, ORANGE and GRAPE. |
| * |
| * @param <E> the enum type |
| */ |
| public class EnumCounters<E extends Enum<E>> { |
| /** The class of the enum. */ |
| private final Class<E> enumClass; |
| /** An array of longs corresponding to the enum type. */ |
| private final long[] counters; |
| |
| /** |
| * Construct counters for the given enum constants. |
| * @param enumClass the enum class of the counters. |
| */ |
| public EnumCounters(final Class<E> enumClass) { |
| final E[] enumConstants = enumClass.getEnumConstants(); |
| Preconditions.checkNotNull(enumConstants); |
| this.enumClass = enumClass; |
| this.counters = new long[enumConstants.length]; |
| } |
| |
| public EnumCounters(final Class<E> enumClass, long defaultVal) { |
| final E[] enumConstants = enumClass.getEnumConstants(); |
| Preconditions.checkNotNull(enumConstants); |
| this.enumClass = enumClass; |
| this.counters = new long[enumConstants.length]; |
| reset(defaultVal); |
| } |
| |
| /** @return the value of counter e. */ |
| public final long get(final E e) { |
| return counters[e.ordinal()]; |
| } |
| |
| /** @return the values of counter as a shadow copy of array*/ |
| public long[] asArray() { |
| return ArrayUtils.clone(counters); |
| } |
| |
| /** Negate all counters. */ |
| public void negation() { |
| for(int i = 0; i < counters.length; i++) { |
| counters[i] = -counters[i]; |
| } |
| } |
| |
| /** Set counter e to the given value. */ |
| public void set(final E e, final long value) { |
| counters[e.ordinal()] = value; |
| } |
| |
| /** Set this counters to that counters. */ |
| public void set(final EnumCounters<E> that) { |
| for(int i = 0; i < counters.length; i++) { |
| this.counters[i] = that.counters[i]; |
| } |
| } |
| |
| /** Reset all counters to zero. */ |
| public void reset() { |
| reset(0L); |
| } |
| |
| /** Add the given value to counter e. */ |
| public void add(final E e, final long value) { |
| counters[e.ordinal()] += value; |
| } |
| |
| /** Add that counters to this counters. */ |
| public void add(final EnumCounters<E> that) { |
| for(int i = 0; i < counters.length; i++) { |
| this.counters[i] += that.counters[i]; |
| } |
| } |
| |
| /** Subtract the given value from counter e. */ |
| public void subtract(final E e, final long value) { |
| counters[e.ordinal()] -= value; |
| } |
| |
| /** Subtract this counters from that counters. */ |
| public void subtract(final EnumCounters<E> that) { |
| for(int i = 0; i < counters.length; i++) { |
| this.counters[i] -= that.counters[i]; |
| } |
| } |
| |
| /** @return the sum of all counters. */ |
| public long sum() { |
| long sum = 0; |
| for(int i = 0; i < counters.length; i++) { |
| sum += counters[i]; |
| } |
| return sum; |
| } |
| |
| @Override |
| public boolean equals(Object obj) { |
| if (obj == this) { |
| return true; |
| } else if (obj == null || !(obj instanceof EnumCounters)) { |
| return false; |
| } |
| final EnumCounters<?> that = (EnumCounters<?>)obj; |
| return this.enumClass == that.enumClass |
| && Arrays.equals(this.counters, that.counters); |
| } |
| |
| /** |
| * Return a deep copy of EnumCounter. |
| */ |
| public EnumCounters<E> deepCopyEnumCounter() { |
| EnumCounters<E> newCounter = new EnumCounters<>(enumClass); |
| newCounter.set(this); |
| return newCounter; |
| } |
| |
| @Override |
| public int hashCode() { |
| return Arrays.hashCode(counters); |
| } |
| |
| @Override |
| public String toString() { |
| final E[] enumConstants = enumClass.getEnumConstants(); |
| final StringBuilder b = new StringBuilder(); |
| for(int i = 0; i < counters.length; i++) { |
| final String name = enumConstants[i].name(); |
| b.append(name).append("=").append(counters[i]).append(", "); |
| } |
| return b.substring(0, b.length() - 2); |
| } |
| |
| public void reset(long val) { |
| for(int i = 0; i < counters.length; i++) { |
| this.counters[i] = val; |
| } |
| } |
| |
| public boolean allLessOrEqual(long val) { |
| for (long c : counters) { |
| if (c > val) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| public boolean anyGreaterOrEqual(long val) { |
| for (long c: counters) { |
| if (c >= val) { |
| return true; |
| } |
| } |
| return false; |
| } |
| } |