Commons Math example source code file (ComplexField.java)

This example Commons Math source code file (ComplexField.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Commons Math tags/keywords

complex, complex, complexfield, complexfield, field, instance, io, lazyholder, object, object, serializable, serializable

The Commons Math ComplexField.java source code

/*
 * 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.math.complex;

import java.io.Serializable;

import org.apache.commons.math.Field;

/**
 * Representation of the complex numbers field.
 * <p>
 * This class is a singleton.
 * </p>
 * @see Complex
 * @version $Revision: 811827 $ $Date: 2009-09-06 11:32:50 -0400 (Sun, 06 Sep 2009) $
 * @since 2.0
 */
public class ComplexField implements Field<Complex>, Serializable  {

    /** Serializable version identifier. */
    private static final long serialVersionUID = -6130362688700788798L;

    /** Private constructor for the singleton.
     */
    private ComplexField() {
    }

    /** Get the unique instance.
     * @return the unique instance
     */
    public static ComplexField getInstance() {
        return LazyHolder.INSTANCE;
    }

    /** {@inheritDoc} */
    public Complex getOne() {
        return Complex.ONE;
    }

    /** {@inheritDoc} */
    public Complex getZero() {
        return Complex.ZERO;
    }

    // CHECKSTYLE: stop HideUtilityClassConstructor
    /** Holder for the instance.
     * <p>We use here the Initialization On Demand Holder Idiom.

     */
    private static class LazyHolder {
        /** Cached field instance. */
        private static final ComplexField INSTANCE = new ComplexField();
    }
    // CHECKSTYLE: resume HideUtilityClassConstructor

    /** Handle deserialization of the singleton.
     * @return the singleton instance
     */
    private Object readResolve() {
        // return the singleton instance
        return LazyHolder.INSTANCE;
    }

}