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Diffstat (limited to 'src/main/java/org/apache/commons/math3/stat/descriptive/SynchronizedDescriptiveStatistics.java')
-rw-r--r-- | src/main/java/org/apache/commons/math3/stat/descriptive/SynchronizedDescriptiveStatistics.java | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/src/main/java/org/apache/commons/math3/stat/descriptive/SynchronizedDescriptiveStatistics.java b/src/main/java/org/apache/commons/math3/stat/descriptive/SynchronizedDescriptiveStatistics.java new file mode 100644 index 0000000..270e4aa --- /dev/null +++ b/src/main/java/org/apache/commons/math3/stat/descriptive/SynchronizedDescriptiveStatistics.java @@ -0,0 +1,192 @@ +/* + * 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.stat.descriptive; + +import org.apache.commons.math3.exception.MathIllegalArgumentException; +import org.apache.commons.math3.exception.NullArgumentException; +import org.apache.commons.math3.util.MathUtils; + +/** + * Implementation of + * {@link org.apache.commons.math3.stat.descriptive.DescriptiveStatistics} that + * is safe to use in a multithreaded environment. Multiple threads can safely + * operate on a single instance without causing runtime exceptions due to race + * conditions. In effect, this implementation makes modification and access + * methods atomic operations for a single instance. That is to say, as one + * thread is computing a statistic from the instance, no other thread can modify + * the instance nor compute another statistic. + * + * @since 1.2 + */ +public class SynchronizedDescriptiveStatistics extends DescriptiveStatistics { + + /** Serialization UID */ + private static final long serialVersionUID = 1L; + + /** + * Construct an instance with infinite window + */ + public SynchronizedDescriptiveStatistics() { + // no try-catch or advertized IAE because arg is valid + this(INFINITE_WINDOW); + } + + /** + * Construct an instance with finite window + * @param window the finite window size. + * @throws MathIllegalArgumentException if window size is less than 1 but + * not equal to {@link #INFINITE_WINDOW} + */ + public SynchronizedDescriptiveStatistics(int window) throws MathIllegalArgumentException { + super(window); + } + + /** + * A copy constructor. Creates a deep-copy of the {@code original}. + * + * @param original the {@code SynchronizedDescriptiveStatistics} instance to copy + * @throws NullArgumentException if original is null + */ + public SynchronizedDescriptiveStatistics(SynchronizedDescriptiveStatistics original) + throws NullArgumentException { + copy(original, this); + } + + /** + * {@inheritDoc} + */ + @Override + public synchronized void addValue(double v) { + super.addValue(v); + } + + /** + * {@inheritDoc} + */ + @Override + public synchronized double apply(UnivariateStatistic stat) { + return super.apply(stat); + } + + /** + * {@inheritDoc} + */ + @Override + public synchronized void clear() { + super.clear(); + } + + /** + * {@inheritDoc} + */ + @Override + public synchronized double getElement(int index) { + return super.getElement(index); + } + + /** + * {@inheritDoc} + */ + @Override + public synchronized long getN() { + return super.getN(); + } + + /** + * {@inheritDoc} + */ + @Override + public synchronized double getStandardDeviation() { + return super.getStandardDeviation(); + } + + /** + * {@inheritDoc} + */ + @Override + public synchronized double getQuadraticMean() { + return super.getQuadraticMean(); + } + + /** + * {@inheritDoc} + */ + @Override + public synchronized double[] getValues() { + return super.getValues(); + } + + /** + * {@inheritDoc} + */ + @Override + public synchronized int getWindowSize() { + return super.getWindowSize(); + } + + /** + * {@inheritDoc} + */ + @Override + public synchronized void setWindowSize(int windowSize) throws MathIllegalArgumentException { + super.setWindowSize(windowSize); + } + + /** + * {@inheritDoc} + */ + @Override + public synchronized String toString() { + return super.toString(); + } + + /** + * Returns a copy of this SynchronizedDescriptiveStatistics instance with the + * same internal state. + * + * @return a copy of this + */ + @Override + public synchronized SynchronizedDescriptiveStatistics copy() { + SynchronizedDescriptiveStatistics result = + new SynchronizedDescriptiveStatistics(); + // No try-catch or advertised exception because arguments are guaranteed non-null + copy(this, result); + return result; + } + + /** + * Copies source to dest. + * <p>Neither source nor dest can be null.</p> + * <p>Acquires synchronization lock on source, then dest before copying.</p> + * + * @param source SynchronizedDescriptiveStatistics to copy + * @param dest SynchronizedDescriptiveStatistics to copy to + * @throws NullArgumentException if either source or dest is null + */ + public static void copy(SynchronizedDescriptiveStatistics source, + SynchronizedDescriptiveStatistics dest) + throws NullArgumentException { + MathUtils.checkNotNull(source); + MathUtils.checkNotNull(dest); + synchronized (source) { + synchronized (dest) { + DescriptiveStatistics.copy(source, dest); + } + } + } +} |