| /* |
| * 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.wayang.core.optimizer.costs; |
| |
| import org.apache.wayang.core.optimizer.ProbabilisticIntervalEstimate; |
| import org.apache.wayang.core.util.JsonSerializable; |
| import org.apache.wayang.core.util.JsonSerializables; |
| import org.apache.wayang.core.util.json.JSONObject; |
| |
| /** |
| * An estimate of costs of some executable code expressed as a {@link ProbabilisticIntervalEstimate}. |
| */ |
| public class LoadEstimate extends ProbabilisticIntervalEstimate implements JsonSerializable { |
| |
| public LoadEstimate(long exactValue) { |
| this(exactValue, exactValue, 1d); |
| } |
| |
| public LoadEstimate(long lowerEstimate, long upperEstimate, double correctnessProb) { |
| super(lowerEstimate, upperEstimate, correctnessProb); |
| } |
| |
| /** |
| * Multiplies the estimated load. The correctness probability is not altered. |
| * |
| * @param n scalar to multiply with |
| * @return the product |
| */ |
| public LoadEstimate times(int n) { |
| return new LoadEstimate(this.getLowerEstimate() * n, this.getUpperEstimate() * n, this.getCorrectnessProbability()); |
| } |
| |
| /** |
| * Adds a this and the given instance. |
| * |
| * @param that the other summand |
| * @return a new instance representing the sum |
| */ |
| public LoadEstimate plus(LoadEstimate that) { |
| return new LoadEstimate( |
| this.getLowerEstimate() + that.getLowerEstimate(), |
| this.getUpperEstimate() + that.getUpperEstimate(), |
| this.getCorrectnessProbability() * that.getCorrectnessProbability() |
| ); |
| } |
| |
| /** |
| * Adds a the and the given instances. |
| * |
| * @param estimate1 the one summand or {@code null} |
| * @param estimate2 the other summand or {@code null} |
| * @return a new instance representing the sum or {@code null} if both summands are {@code null} |
| */ |
| public static LoadEstimate add(LoadEstimate estimate1, LoadEstimate estimate2) { |
| return estimate1 == null ? |
| estimate2 : |
| (estimate2 == null ? estimate1 : estimate1.plus(estimate2)); |
| } |
| |
| @Override |
| public JSONObject toJson() { |
| JSONObject json = new JSONObject(); |
| json.put("lower", JsonSerializables.serialize(this.getLowerEstimate(), false)); |
| json.put("upper", JsonSerializables.serialize(this.getUpperEstimate(), false)); |
| json.put("prob", JsonSerializables.serialize(this.getCorrectnessProbability(), false)); |
| return json; |
| } |
| |
| @SuppressWarnings("unused") |
| public static LoadEstimate fromJson(JSONObject jsonObject) { |
| return new LoadEstimate( |
| jsonObject.getLong("lower"), |
| jsonObject.getLong("upper"), |
| jsonObject.getDouble("prob") |
| ); |
| } |
| } |