# CustomerEntity.java

    package org.example.customer.utility;

    /*
     * This is free and unencumbered software released into the public domain.
     * Anyone is free to copy, modify, publish, use, compile, sell, or distribute this software,
     * either in source code form or as a compiled binary, for any purpose, commercial or
     * non-commercial, and by any means.
     *
     * In jurisdictions that recognize copyright laws, the author or authors of this
     * software dedicate any and all copyright interest in the software to the public domain.
     * We make this dedication for the benefit of the public at large and to the detriment of
     * our heirs and successors. We intend this dedication to be an overt act of relinquishment in
     * perpetuity of all present and future rights to this software under copyright law.
     *
     * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
     * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
     * PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES
     * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
     * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
     *
     * For more information, please refer to: https://unlicense.org/
    */

    import java.io.Serializable;

    import org.apache.commons.lang3.builder.EqualsBuilder;
    import org.apache.commons.lang3.builder.HashCodeBuilder;
    import org.apache.logging.log4j.LogManager;
    import org.apache.logging.log4j.Logger;

    /**
     * The Customer Entity for the Customer application.
     <br>
     <br>
     * This class represents the common Id field in the Customer Database
     *
     * @author Jonathan Earl
     * @version 1.0
     *
     */
    public class CustomerEntity
        implements Serializable
    {
        private static final long serialVersionUID = 1L;

        private static final Logger LOG = LogManager.getLogger();

        private int myId;

        /**
         * The default constructor for the CustomerEntity class.
         * <p>
         * The initial values are:
         * <ul>
         *   <li>id: 1</li>
         * </ul>
         *
         */
        public CustomerEntity()
        {
            LOG.debug("Starting the default Constructor");
            final int initialId = 1;

            setId(initialId);
        }

        /**
         * Returns the id value for the Customer.
         *
         * @return the id value for the customer
         */
        public int getId()
        {
            LOG.debug("returning the Id: " + myId);
            return myId;
        }

        /**
         * Sets the id value for the Customer.
         * <p>
         * The business rules are:
         * <ul>
         *   <li>the id must be 1 or greater</li>
         * </ul>
         *
         * @param id the value to set into the customer id field
         * @throws IllegalArgumentException if the id is invalid
         */
        public void setId(final int id)
        {
            LOG.debug("setting the Id: " + id);
            final int min = 1;

            if (id < min)
            {
                LOG.error("Id must be greater then zero");
                throw new IllegalArgumentException("Id must be greater then zero");
            }
            this.myId = id;
        }

        /**
         * The hashCode() method of the CustomerEntity class.
         * <p>
         * <strong>This method uses:</strong>
         * <ul>
         *  <li>id</li>
         * </ul>
         *
         * @see java.lang.Object#hashCode()
         * @return the hashCode value for this CustomerEntity object
         */
        @Override
        public int hashCode()
        {
            LOG.debug("building HashCode");
            return new HashCodeBuilder()
                    .append(getId())
                    .toHashCode();
        }

        /**
         * The equals() method of the CustomerEntity class.
         * <p>
         * <strong>This method uses:</strong>
         * <ul>
         *  <li>id</li>
         * </ul>
         *
         * @see java.lang.Object#equals(Object obj)
         * @param obj the incoming object to compare against
         * @return true if the fields being compared are equal
         */
        @Override
        public boolean equals(final Object obj)
        {
            LOG.debug("checking equals");
            if (obj instanceof CustomerEntity)
            {
                final CustomerEntity other = (CustomerEntity) obj;
                return new EqualsBuilder()
                        .append(getId(), other.getId())
                        .isEquals();
            }
            else
            {
                return false;
            }
        }

        /**
         * The toString method for the CustomerEntity class.
         *
         * this method will return:<br>
         * CustomerEntity [Id=xxx]
         */
        @Override
        public String toString()
        {
            return "CustomerEntity [Id=" + getId() + "]";
        }
    }