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A single bundled dependency that includes all service and dependent JARs with third-party libraries relocated to different namespaces.

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/*
 * Copyright 2010-2018 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License").
 * You may not use this file except in compliance with the License.
 * A copy of the License is located at
 *
 *  http://aws.amazon.com/apache2.0
 *
 * or in the "license" file accompanying this file. This file 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 software.amazon.awssdk.utils;

import javax.xml.XMLConstants;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.stream.XMLInputFactory;
import software.amazon.awssdk.annotations.SdkProtectedApi;

@SdkProtectedApi
public final class XmlUtils {

    /**
     * Shared factory for creating XML event readers
     */
    private static final ThreadLocal XML_INPUT_FACTORY =
        ThreadLocal.withInitial(XmlUtils::createXmlInputFactory);

    private XmlUtils() {
    }

    /**
     * @return A {@link ThreadLocal} copy of {@link XMLInputFactory}.
     */
    public static XMLInputFactory xmlInputFactory() {
        return XML_INPUT_FACTORY.get();
    }

    /**
     * Disables certain dangerous features that attempt to automatically fetch DTDs
     *
     * See OWASP XXE Cheat Sheet
     */
    public static DocumentBuilderFactory documentBuilderFactory() throws ParserConfigurationException {
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        factory.setFeature(XMLConstants.FEATURE_SECURE_PROCESSING, true);
        factory.setFeature("http://xml.org/sax/features/external-general-entities", false);
        factory.setFeature("http://xml.org/sax/features/external-parameter-entities", false);
        return factory;
    }

    /**
     * Disables certain dangerous features that attempt to automatically fetch DTDs
     *
     * See OWASP XXE Cheat Sheet
     */
    private static XMLInputFactory createXmlInputFactory() {
        XMLInputFactory factory = XMLInputFactory.newInstance();
        factory.setProperty(XMLInputFactory.SUPPORT_DTD, false);
        factory.setProperty(XMLInputFactory.IS_SUPPORTING_EXTERNAL_ENTITIES, false);
        return factory;
    }
}