ContentTypeImpl.java

/**
 * Copyright (c) Codice Foundation
 * <p>
 * This is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser
 * General Public License as published by the Free Software Foundation, either version 3 of the
 * License, or any later version.
 * <p>
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
 * even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details. A copy of the GNU Lesser General Public License
 * is distributed along with this program and can be found at
 * <http://www.gnu.org/licenses/lgpl.html>.
 */
package ddf.catalog.data.impl;

import java.net.URI;

import ddf.catalog.data.ContentType;

/**
 * This class is a common implementation of the {@link ContentType} interface.
 *
 * It is used to return the list of {@link ContentType}s currently stored in a {@link Source}.
 *
 * @author ddf.isgs@lmco.com
 *
 */
public class ContentTypeImpl implements ContentType {

    private static final int HASHCODE_OFFSET = 17;

    /**
     * This value was chosen because it is an odd prime. It can be also replaced by a shift and a
     * subtraction for better performance, which most VMs do these days. (For more information, read
     * <i>Item 9</i> in <u>Effective Java</u>, Second Edition)
     */
    private static final int HASHCODE_MULTIPLIER = 31;

    /**
     * Name of the content type.
     */
    protected String name;

    /**
     * Version of the content type.
     */
    protected String version;

    /**
     * Namespace of the content type.
     */
    protected URI namespace;

    public ContentTypeImpl() {
    }

    /**
     * @param name
     *            the name of the {@link ContentType}
     * @param version
     *            the version of the {@link ContentType}
     */
    public ContentTypeImpl(String name, String version) {
        this(name, version, null);
    }

    /**
     * @param name
     *            the name of the {@link ContentType}
     * @param version
     *            the version of the {@link ContentType}
     * @param targetNamespace
     *            the namespace of the {@link ContentType}
     */
    public ContentTypeImpl(String name, String version, URI targetNamespace) {
        this.name = name;
        this.version = version;
        this.namespace = targetNamespace;
    }

    @Override
    public String getName() {
        return name;
    }

    /**
     * Sets the name of the content type.
     *
     * @param name
     *            the name of the content type
     */
    public void setName(String name) {
        this.name = name;
    }

    @Override
    public String getVersion() {
        return version;
    }

    /**
     * Sets the version of the content type.
     *
     * @param version
     *            the version of the content type
     */
    public void setVersion(String version) {
        this.version = version;
    }

    @Override
    public URI getNamespace() {
        return namespace;
    }

    /**
     * Sets the namespace of the content type.
     *
     * @param namespace
     *            the namespace of the content type
     */
    public void setNamespace(URI namespace) {
        this.namespace = namespace;
    }

    @Override
    public int hashCode() {

        /*
         * Any major changes to this method, requires changes in the equals method.
         */

        int result = HASHCODE_OFFSET;

        result = HASHCODE_MULTIPLIER * result + ((name != null) ? name.hashCode() : 0);

        result = HASHCODE_MULTIPLIER * result + ((version != null) ? version.hashCode() : 0);

        result = HASHCODE_MULTIPLIER * result + ((namespace != null) ? namespace.hashCode() : 0);

        return result;

    }

    @Override
    public boolean equals(Object obj) {

        /*
         * Any major changes to this method such as adding a field check, requires changes in the
         * hashCode method. According to the Java Object Specification, "If two objects are equal
         * according to the equals(Object) method, then calling the hashCode method on each of the
         * two objects must produce the same integer result."
         */

        if (!(obj instanceof ContentType)) {
            return false;
        }

        ContentType newObject = (ContentType) obj;

        if (this.getName() == null) {
            if (newObject.getName() != null) {
                return false;
            }
        } else if (!this.getName()
                .equals(newObject.getName())) {
            return false;
        }

        if (this.getVersion() == null) {
            if (newObject.getVersion() != null) {
                return false;
            }
        } else if (!this.getVersion()
                .equals(newObject.getVersion())) {
            return false;
        }

        if (this.getNamespace() == null) {
            if (newObject.getNamespace() != null) {
                return false;
            }
        } else if (!this.getNamespace()
                .equals(newObject.getNamespace())) {
            return false;
        }

        return true;
    }
}