| /** |
| * 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 java.util.Arrays; |
| |
| import com.google.common.base.Preconditions; |
| |
| /** |
| * Similar to {@link EnumCounters} except that the value type is double. |
| * |
| * @param <E> the enum type |
| */ |
| public class EnumDoubles<E extends Enum<E>> { |
| /** The class of the enum. */ |
| private final Class<E> enumClass; |
| /** An array of doubles corresponding to the enum type. */ |
| private final double[] doubles; |
| |
| /** |
| * Construct doubles for the given enum constants. |
| * @param enumClass the enum class. |
| */ |
| public EnumDoubles(final Class<E> enumClass) { |
| final E[] enumConstants = enumClass.getEnumConstants(); |
| Preconditions.checkNotNull(enumConstants); |
| this.enumClass = enumClass; |
| this.doubles = new double[enumConstants.length]; |
| } |
| |
| /** @return the value corresponding to e. */ |
| public final double get(final E e) { |
| return doubles[e.ordinal()]; |
| } |
| |
| /** Negate all values. */ |
| public final void negation() { |
| for(int i = 0; i < doubles.length; i++) { |
| doubles[i] = -doubles[i]; |
| } |
| } |
| |
| /** Set e to the given value. */ |
| public final void set(final E e, final double value) { |
| doubles[e.ordinal()] = value; |
| } |
| |
| /** Set the values of this object to that object. */ |
| public final void set(final EnumDoubles<E> that) { |
| for(int i = 0; i < doubles.length; i++) { |
| this.doubles[i] = that.doubles[i]; |
| } |
| } |
| |
| /** Reset all values to zero. */ |
| public final void reset() { |
| for(int i = 0; i < doubles.length; i++) { |
| this.doubles[i] = 0.0; |
| } |
| } |
| |
| /** Add the given value to e. */ |
| public final void add(final E e, final double value) { |
| doubles[e.ordinal()] += value; |
| } |
| |
| /** Add the values of that object to this. */ |
| public final void add(final EnumDoubles<E> that) { |
| for(int i = 0; i < doubles.length; i++) { |
| this.doubles[i] += that.doubles[i]; |
| } |
| } |
| |
| /** Subtract the given value from e. */ |
| public final void subtract(final E e, final double value) { |
| doubles[e.ordinal()] -= value; |
| } |
| |
| /** Subtract the values of this object from that object. */ |
| public final void subtract(final EnumDoubles<E> that) { |
| for(int i = 0; i < doubles.length; i++) { |
| this.doubles[i] -= that.doubles[i]; |
| } |
| } |
| |
| @Override |
| public boolean equals(Object obj) { |
| if (obj == this) { |
| return true; |
| } else if (obj == null || !(obj instanceof EnumDoubles)) { |
| return false; |
| } |
| final EnumDoubles<?> that = (EnumDoubles<?>)obj; |
| return this.enumClass == that.enumClass |
| && Arrays.equals(this.doubles, that.doubles); |
| } |
| |
| @Override |
| public int hashCode() { |
| return Arrays.hashCode(doubles); |
| } |
| |
| @Override |
| public String toString() { |
| final E[] enumConstants = enumClass.getEnumConstants(); |
| final StringBuilder b = new StringBuilder(); |
| for(int i = 0; i < doubles.length; i++) { |
| final String name = enumConstants[i].name(); |
| b.append(name).append("=").append(doubles[i]).append(", "); |
| } |
| return b.substring(0, b.length() - 2); |
| } |
| } |