diff --git a/src/changes/changes.xml b/src/changes/changes.xml index 1fb75224a..92f4747e2 100644 --- a/src/changes/changes.xml +++ b/src/changes/changes.xml @@ -52,6 +52,11 @@ If the output is not quite correct, check for invisible trailing spaces! + + Added a new "SynchronizedRandomGenerator" that wraps another + "RandomGenerator" with all methods being synchronized, thus + rendering the code thread-safe (at some efficiency cost). + Add new "NaNStrategy": FAILED, used in "RankingAlgorithm" implementations. Any encountered input value that succeeds a "Double#isNaN" check, results in a diff --git a/src/main/java/org/apache/commons/math3/random/SynchronizedRandomGenerator.java b/src/main/java/org/apache/commons/math3/random/SynchronizedRandomGenerator.java new file mode 100644 index 000000000..54c006dee --- /dev/null +++ b/src/main/java/org/apache/commons/math3/random/SynchronizedRandomGenerator.java @@ -0,0 +1,122 @@ +/* + * 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.commons.math3.random; + +/** + * Any {@link RandomGenerator} implementation can be thread-safe if it + * is used through an instance of this class. + * This is achieved by enclosing calls to the methods of the actual + * generator inside the overridden {@code synchronized} methods of this + * class. + * + * @since 3.1 + * @version $Id$ + */ +public class SynchronizedRandomGenerator implements RandomGenerator { + /** Object to which all calls will be delegated. */ + private final RandomGenerator wrapped; + + /** + * Creates a synchronized wrapper for the given {@code RandomGenerator} + * instance. + * + * @param rng Generator whose methods will be called through + * their corresponding overridden synchronized version. + * To ensure thread-safety, the wrapped generator must + * not be used directly. + */ + public SynchronizedRandomGenerator(RandomGenerator rng) { + wrapped = rng; + } + + /** + * {@inheritDoc} + */ + public synchronized void setSeed(int seed) { + wrapped.setSeed(seed); + } + + /** + * {@inheritDoc} + */ + public synchronized void setSeed(int[] seed) { + wrapped.setSeed(seed); + } + + /** + * {@inheritDoc} + */ + public synchronized void setSeed(long seed) { + wrapped.setSeed(seed); + } + + /** + * {@inheritDoc} + */ + public synchronized void nextBytes(byte[] bytes) { + wrapped.nextBytes(bytes); + } + + /** + * {@inheritDoc} + */ + public synchronized int nextInt() { + return wrapped.nextInt(); + } + + /** + * {@inheritDoc} + */ + public synchronized int nextInt(int n) { + return wrapped.nextInt(); + } + + /** + * {@inheritDoc} + */ + public synchronized long nextLong() { + return wrapped.nextLong(); + } + + /** + * {@inheritDoc} + */ + public synchronized boolean nextBoolean() { + return wrapped.nextBoolean(); + } + + /** + * {@inheritDoc} + */ + public synchronized float nextFloat() { + return wrapped.nextFloat(); + } + + /** + * {@inheritDoc} + */ + public synchronized double nextDouble() { + return wrapped.nextDouble(); + } + + /** + * {@inheritDoc} + */ + public synchronized double nextGaussian() { + return wrapped.nextGaussian(); + } +}