java/10 : java.xml.ws/com/sun/xml/internal/ws/api/streaming/XMLStreamReaderFactory.java

XMLStreamReaderFactory
https://openjdk.java.net/
GPLv2 + Classpath Exception
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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 General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
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package com.sun.xml.internal.ws.api.streaming;

import com.sun.istack.internal.NotNull;
import com.sun.istack.internal.Nullable;
import com.sun.xml.internal.ws.streaming.XMLReaderException;
import com.sun.xml.internal.ws.util.MrJarUtil;
import com.sun.xml.internal.ws.util.xml.XmlUtil;
import org.xml.sax.InputSource;

import javax.xml.stream.XMLInputFactory;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.io.StringReader;
import java.io.UnsupportedEncodingException;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.net.URL;
import java.security.AccessController;
import java.util.logging.Level;
import java.util.logging.Logger;

import com.sun.xml.internal.ws.resources.StreamingMessages;

Factory for XMLStreamReader.  This wraps XMLInputFactory and allows us to reuse XMLStreamReader instances when appropriate. 
Author: Kohsuke Kawaguchi/**
 * Factory for {@link XMLStreamReader}.
 *
 * <p>
 * This wraps {@link XMLInputFactory} and allows us to reuse {@link XMLStreamReader} instances
 * when appropriate.
 *
 * @author Kohsuke Kawaguchi
 */
@SuppressWarnings("StaticNonFinalUsedInInitialization")
public abstract class XMLStreamReaderFactory {

    private static final Logger LOGGER = Logger.getLogger(XMLStreamReaderFactory.class.getName());

    private static final String CLASS_NAME_OF_WSTXINPUTFACTORY = "com.ctc.wstx.stax.WstxInputFactory";

    Singleton instance.
/**
     * Singleton instance.
     */
    private static volatile ContextClassloaderLocal<XMLStreamReaderFactory> streamReader =
            new ContextClassloaderLocal<XMLStreamReaderFactory>() {

                @Override
                protected XMLStreamReaderFactory initialValue() {

                    XMLInputFactory xif = getXMLInputFactory();
                    XMLStreamReaderFactory f=null;

                    // this system property can be used to disable the pooling altogether,
                    // in case someone hits an issue with pooling in the production system.
                    if(!MrJarUtil.getNoPoolProperty(XMLStreamReaderFactory.class.getName())) {
                        f = Zephyr.newInstance(xif);
                    }

                    if(f==null) {
                        // is this Woodstox?
                        if (xif.getClass().getName().equals(CLASS_NAME_OF_WSTXINPUTFACTORY)) {
                            f = new Woodstox(xif);
                        }
                    }

                    if (f==null) {
                        f = new Default();
                    }

                    if (LOGGER.isLoggable(Level.FINE)) {
                        LOGGER.log(Level.FINE, "XMLStreamReaderFactory instance is = {0}", f);
                    }
                    return f;
                }
            };

    private static XMLInputFactory getXMLInputFactory() {
        XMLInputFactory xif = null;
        if (getProperty(XMLStreamReaderFactory.class.getName()+".woodstox")) {
            try {
                xif = (XMLInputFactory)Class.forName("com.ctc.wstx.stax.WstxInputFactory").newInstance();
            } catch (Exception e) {
                if (LOGGER.isLoggable(Level.WARNING)) {
                    LOGGER.log(Level.WARNING, StreamingMessages.WOODSTOX_CANT_LOAD(CLASS_NAME_OF_WSTXINPUTFACTORY), e);
                }
            }
        }
        if (xif == null) {
             xif = XmlUtil.newXMLInputFactory(true);
        }
        xif.setProperty(XMLInputFactory.IS_NAMESPACE_AWARE, true);
        xif.setProperty(XMLInputFactory.SUPPORT_DTD, false);
        xif.setProperty(XMLInputFactory.IS_COALESCING, true);

        return xif;
    }

    Overrides the singleton XMLStreamReaderFactory instance that the JAX-WS RI uses. /**
     * Overrides the singleton {@link XMLStreamReaderFactory} instance that
     * the JAX-WS RI uses.
     */
    public static void set(XMLStreamReaderFactory f) {
        if(f==null) {
            throw new IllegalArgumentException();
        }
        streamReader.set(f);
    }

    public static XMLStreamReaderFactory get() {
        return streamReader.get();
    }

    public static XMLStreamReader create(InputSource source, boolean rejectDTDs) {
        try {
            // Char stream available?
            if (source.getCharacterStream() != null) {
                return get().doCreate(source.getSystemId(), source.getCharacterStream(), rejectDTDs);
            }

            // Byte stream available?
            if (source.getByteStream() != null) {
                return get().doCreate(source.getSystemId(), source.getByteStream(), rejectDTDs);
            }

            // Otherwise, open URI
            return get().doCreate(source.getSystemId(), new URL(source.getSystemId()).openStream(),rejectDTDs);
        } catch (IOException e) {
            throw new XMLReaderException("stax.cantCreate",e);
        }
    }

    public static XMLStreamReader create(@Nullable String systemId, InputStream in, boolean rejectDTDs) {
        return get().doCreate(systemId,in,rejectDTDs);
    }

    public static XMLStreamReader create(@Nullable String systemId, InputStream in, @Nullable String encoding, boolean rejectDTDs) {
        return (encoding == null)
                ? create(systemId, in, rejectDTDs)
                : get().doCreate(systemId,in,encoding,rejectDTDs);
    }

    public static XMLStreamReader create(@Nullable String systemId, Reader reader, boolean rejectDTDs) {
        return get().doCreate(systemId,reader,rejectDTDs);
    }

    Should be invoked when the code finished using an XMLStreamReader.  If the recycled instance implements RecycleAware, RecycleAware.onRecycled() will be invoked to let the instance know that it's being recycled. 
 It is not a hard requirement to call this method on every XMLStreamReader instance. Not doing so just reduces the performance by throwing away possibly reusable instances. So the caller should always consider the effort it takes to recycle vs the possible performance gain by doing so. 

This method may be invoked by multiple threads concurrently.
Params: r –  The XMLStreamReader instance that the caller finished using. This could be any XMLStreamReader implementation, not just the ones that were created from this factory. So the implementation of this class needs to be aware of that./**
     * Should be invoked when the code finished using an {@link XMLStreamReader}.
     *
     * <p>
     * If the recycled instance implements {@link RecycleAware},
     * {@link RecycleAware#onRecycled()} will be invoked to let the instance
     * know that it's being recycled.
     *
     * <p>
     * It is not a hard requirement to call this method on every {@link XMLStreamReader}
     * instance. Not doing so just reduces the performance by throwing away
     * possibly reusable instances. So the caller should always consider the effort
     * it takes to recycle vs the possible performance gain by doing so.
     *
     * <p>
     * This method may be invoked by multiple threads concurrently.
     *
     * @param r
     *      The {@link XMLStreamReader} instance that the caller finished using.
     *      This could be any {@link XMLStreamReader} implementation, not just
     *      the ones that were created from this factory. So the implementation
     *      of this class needs to be aware of that.
     */
    public static void recycle(XMLStreamReader r) {
     /* the XMLStreamReaderFactory recycle becomes expenisve in the threadLocal get operation.
        get().doRecycle(r);
        if (r instanceof RecycleAware) {
            ((RecycleAware)r).onRecycled();
        }*/
    }

    // implementations

    public abstract XMLStreamReader doCreate(String systemId, InputStream in, boolean rejectDTDs);

    private XMLStreamReader doCreate(String systemId, InputStream in, @NotNull String encoding, boolean rejectDTDs) {
        Reader reader;
        try {
            reader = new InputStreamReader(in, encoding);
        } catch(UnsupportedEncodingException ue) {
            throw new XMLReaderException("stax.cantCreate", ue);
        }
        return doCreate(systemId, reader, rejectDTDs);
    }

    public abstract XMLStreamReader doCreate(String systemId, Reader reader, boolean rejectDTDs);

    public abstract void doRecycle(XMLStreamReader r);

    Interface that can be implemented by XMLStreamReader to be notified when it's recycled.  This provides a filtering XMLStreamReader an opportunity to recycle its inner XMLStreamReader. /**
     * Interface that can be implemented by {@link XMLStreamReader} to
     * be notified when it's recycled.
     *
     * <p>
     * This provides a filtering {@link XMLStreamReader} an opportunity to
     * recycle its inner {@link XMLStreamReader}.
     */
    public interface RecycleAware {
        void onRecycled();
    }

    XMLStreamReaderFactory implementation for SJSXP/JAXP RI. /**
     * {@link XMLStreamReaderFactory} implementation for SJSXP/JAXP RI.
     */
    private static final class Zephyr extends XMLStreamReaderFactory {
        private final XMLInputFactory xif;

        private final ThreadLocal<XMLStreamReader> pool = new ThreadLocal<XMLStreamReader>();

        Sun StAX impl XMLReaderImpl.setInputSource() method via reflection.
/**
         * Sun StAX impl <code>XMLReaderImpl.setInputSource()</code> method via reflection.
         */
        private final Method setInputSourceMethod;

        Sun StAX impl XMLReaderImpl.reset() method via reflection.
/**
         * Sun StAX impl <code>XMLReaderImpl.reset()</code> method via reflection.
         */
        private final Method resetMethod;

        The Sun StAX impl's XMLStreamReader implementation clas. /**
         * The Sun StAX impl's {@link XMLStreamReader} implementation clas.
         */
        private final Class zephyrClass;

        Creates Zephyr instance if the given XMLInputFactory is the one from Zephyr. /**
         * Creates {@link Zephyr} instance if the given {@link XMLInputFactory} is the one
         * from Zephyr.
         */
        public static @Nullable
        XMLStreamReaderFactory newInstance(XMLInputFactory xif) {
            // check if this is from Zephyr
            try {
                Class<?> clazz = xif.createXMLStreamReader(new StringReader("<foo/>")).getClass();
                // JDK has different XMLStreamReader impl class. Even if we check for that,
                // it doesn't have setInputSource(InputSource). Let it use Default
                if(!(clazz.getName().startsWith("com.sun.xml.internal.stream.")) )
                    return null;    // nope
                return new Zephyr(xif,clazz);
            } catch (NoSuchMethodException e) {
                return null;    // this factory is not for zephyr
            } catch (XMLStreamException e) {
                return null;    // impossible to fail to parse <foo/>, but anyway
            }
        }

        public Zephyr(XMLInputFactory xif, Class clazz) throws NoSuchMethodException {
            zephyrClass = clazz;
            setInputSourceMethod = clazz.getMethod("setInputSource", InputSource.class);
            resetMethod = clazz.getMethod("reset");

            try {
                // Turn OFF internal factory caching in Zephyr.
                // Santiago told me that this makes it thread-safe.
                xif.setProperty("reuse-instance", false);
            } catch (IllegalArgumentException e) {
                // falls through
            }
            this.xif = xif;
        }

        Fetchs an instance from the pool if available, otherwise null.
/**
         * Fetchs an instance from the pool if available, otherwise null.
         */
        private @Nullable XMLStreamReader fetch() {
            XMLStreamReader sr = pool.get();
            if(sr==null)    return null;
            pool.set(null);
            return sr;
        }

        @Override
        public void doRecycle(XMLStreamReader r) {
            if(zephyrClass.isInstance(r))
                pool.set(r);
        }

        @Override
        public XMLStreamReader doCreate(String systemId, InputStream in, boolean rejectDTDs) {
            try {
                XMLStreamReader xsr = fetch();
                if(xsr==null)
                    return xif.createXMLStreamReader(systemId,in);

                // try re-using this instance.
                InputSource is = new InputSource(systemId);
                is.setByteStream(in);
                reuse(xsr,is);
                return xsr;
            } catch (IllegalAccessException e) {
                throw new XMLReaderException("stax.cantCreate",e);
            } catch (InvocationTargetException e) {
                throw new XMLReaderException("stax.cantCreate",e);
            } catch (XMLStreamException e) {
                throw new XMLReaderException("stax.cantCreate",e);
            }
        }

        @Override
        public XMLStreamReader doCreate(String systemId, Reader in, boolean rejectDTDs) {
            try {
                XMLStreamReader xsr = fetch();
                if(xsr==null)
                    return xif.createXMLStreamReader(systemId,in);

                // try re-using this instance.
                InputSource is = new InputSource(systemId);
                is.setCharacterStream(in);
                reuse(xsr,is);
                return xsr;
            } catch (IllegalAccessException e) {
                throw new XMLReaderException("stax.cantCreate",e);
            } catch (InvocationTargetException e) {
                Throwable cause = e.getCause();
                if (cause == null) {
                    cause = e;
                }
                throw new XMLReaderException("stax.cantCreate", cause);
            } catch (XMLStreamException e) {
                throw new XMLReaderException("stax.cantCreate",e);
            }
        }

        private void reuse(XMLStreamReader xsr, InputSource in) throws IllegalAccessException, InvocationTargetException {
            resetMethod.invoke(xsr);
            setInputSourceMethod.invoke(xsr,in);
        }
    }

    Default XMLStreamReaderFactory implementation that can work with any XMLInputFactory.  XMLInputFactory is not required to be thread-safe, but if the create method on this implementation is synchronized, it may run into (see 
race condition). Hence, using a XMLInputFactory per thread.
/**
     * Default {@link XMLStreamReaderFactory} implementation
     * that can work with any {@link XMLInputFactory}.
     *
     * <p>
     * {@link XMLInputFactory} is not required to be thread-safe, but
     * if the create method on this implementation is synchronized,
     * it may run into (see <a href="https://jax-ws.dev.java.net/issues/show_bug.cgi?id=555">
     * race condition</a>). Hence, using a XMLInputFactory per thread.
     */
    public static final class Default extends XMLStreamReaderFactory {

        private final ThreadLocal<XMLInputFactory> xif = new ThreadLocal<XMLInputFactory>() {
            @Override
            public XMLInputFactory initialValue() {
                return getXMLInputFactory();
            }
        };

        @Override
        public XMLStreamReader doCreate(String systemId, InputStream in, boolean rejectDTDs) {
            try {
                return xif.get().createXMLStreamReader(systemId,in);
            } catch (XMLStreamException e) {
                throw new XMLReaderException("stax.cantCreate",e);
            }
        }

        @Override
        public XMLStreamReader doCreate(String systemId, Reader in, boolean rejectDTDs) {
            try {
                return xif.get().createXMLStreamReader(systemId,in);
            } catch (XMLStreamException e) {
                throw new XMLReaderException("stax.cantCreate",e);
            }
        }

        @Override
        public void doRecycle(XMLStreamReader r) {
            // there's no way to recycle with the default StAX API.
        }

    }

    Similar to Default but doesn't do any synchronization.  This is useful when you know your XMLInputFactory is thread-safe by itself. /**
     * Similar to {@link Default} but doesn't do any synchronization.
     *
     * <p>
     * This is useful when you know your {@link XMLInputFactory} is thread-safe by itself.
     */
    public static class NoLock extends XMLStreamReaderFactory {
        private final XMLInputFactory xif;

        public NoLock(XMLInputFactory xif) {
            this.xif = xif;
        }

        @Override
        public XMLStreamReader doCreate(String systemId, InputStream in, boolean rejectDTDs) {
            try {
                return xif.createXMLStreamReader(systemId,in);
            } catch (XMLStreamException e) {
                throw new XMLReaderException("stax.cantCreate",e);
            }
        }

        @Override
        public XMLStreamReader doCreate(String systemId, Reader in, boolean rejectDTDs) {
            try {
                return xif.createXMLStreamReader(systemId,in);
            } catch (XMLStreamException e) {
                throw new XMLReaderException("stax.cantCreate",e);
            }
        }

        @Override
        public void doRecycle(XMLStreamReader r) {
            // there's no way to recycle with the default StAX API.
        }
    }

    Handles Woodstox's XIF, but sets properties to do the string interning, sets various limits, ... Woodstox XMLInputFactory is thread safe. /**
     * Handles Woodstox's XIF, but sets properties to do the string interning, sets various limits, ...
     * Woodstox {@link XMLInputFactory} is thread safe.
     */
    public static final class Woodstox extends NoLock {

        public final static String PROPERTY_MAX_ATTRIBUTES_PER_ELEMENT = "xml.ws.maximum.AttributesPerElement";
        public final static String PROPERTY_MAX_ATTRIBUTE_SIZE = "xml.ws.maximum.AttributeSize";
        public final static String PROPERTY_MAX_CHILDREN_PER_ELEMENT = "xml.ws.maximum.ChildrenPerElement";
        public final static String PROPERTY_MAX_ELEMENT_COUNT = "xml.ws.maximum.ElementCount";
        public final static String PROPERTY_MAX_ELEMENT_DEPTH = "xml.ws.maximum.ElementDepth";
        public final static String PROPERTY_MAX_CHARACTERS = "xml.ws.maximum.Characters";

        private static final int DEFAULT_MAX_ATTRIBUTES_PER_ELEMENT = 500;
        private static final int DEFAULT_MAX_ATTRIBUTE_SIZE = 65536 * 8;
        private static final int DEFAULT_MAX_CHILDREN_PER_ELEMENT = Integer.MAX_VALUE;
        private static final int DEFAULT_MAX_ELEMENT_DEPTH = 500;
        private static final long DEFAULT_MAX_ELEMENT_COUNT = Integer.MAX_VALUE;
        private static final long DEFAULT_MAX_CHARACTERS = Long.MAX_VALUE;

        /* Woodstox default setting:
         int mMaxAttributesPerElement = 1000;
         int mMaxAttributeSize = 65536 * 8;
         int mMaxChildrenPerElement = Integer.MAX_VALUE;
         int mMaxElementDepth = 1000;
         long mMaxElementCount = Long.MAX_VALUE;
         long mMaxCharacters = Long.MAX_VALUE;
         */

        private int maxAttributesPerElement = DEFAULT_MAX_ATTRIBUTES_PER_ELEMENT;
        private int maxAttributeSize = DEFAULT_MAX_ATTRIBUTE_SIZE;
        private int maxChildrenPerElement = DEFAULT_MAX_CHILDREN_PER_ELEMENT;
        private int maxElementDepth = DEFAULT_MAX_ELEMENT_DEPTH;
        private long maxElementCount = DEFAULT_MAX_ELEMENT_COUNT;
        private long maxCharacters = DEFAULT_MAX_CHARACTERS;

        // Note: this is a copy from com.ctc.wstx.api.WstxInputProperties, to be removed in the future
        private static final java.lang.String P_MAX_ATTRIBUTES_PER_ELEMENT = "com.ctc.wstx.maxAttributesPerElement";
        private static final java.lang.String P_MAX_ATTRIBUTE_SIZE = "com.ctc.wstx.maxAttributeSize";
        private static final java.lang.String P_MAX_CHILDREN_PER_ELEMENT = "com.ctc.wstx.maxChildrenPerElement";
        private static final java.lang.String P_MAX_ELEMENT_COUNT = "com.ctc.wstx.maxElementCount";
        private static final java.lang.String P_MAX_ELEMENT_DEPTH = "com.ctc.wstx.maxElementDepth";
        private static final java.lang.String P_MAX_CHARACTERS = "com.ctc.wstx.maxCharacters";
        private static final java.lang.String P_INTERN_NSURIS = "org.codehaus.stax2.internNsUris";
        private static final java.lang.String P_RETURN_NULL_FOR_DEFAULT_NAMESPACE = "com.ctc.wstx.returnNullForDefaultNamespace";

        public Woodstox(XMLInputFactory xif) {
            super(xif);

            if (xif.isPropertySupported(P_INTERN_NSURIS)) {
                xif.setProperty(P_INTERN_NSURIS, true);
                if (LOGGER.isLoggable(Level.FINE)) {
                    LOGGER.log(Level.FINE, P_INTERN_NSURIS + " is {0}", true);
                }
            }

            if (xif.isPropertySupported(P_MAX_ATTRIBUTES_PER_ELEMENT)) {
                maxAttributesPerElement = Integer.valueOf(buildIntegerValue(
                    PROPERTY_MAX_ATTRIBUTES_PER_ELEMENT, DEFAULT_MAX_ATTRIBUTES_PER_ELEMENT)
                );
                xif.setProperty(P_MAX_ATTRIBUTES_PER_ELEMENT, maxAttributesPerElement);
                if (LOGGER.isLoggable(Level.FINE)) {
                    LOGGER.log(Level.FINE, P_MAX_ATTRIBUTES_PER_ELEMENT + " is {0}", maxAttributesPerElement);
                }
            }

            if (xif.isPropertySupported(P_MAX_ATTRIBUTE_SIZE)) {
                maxAttributeSize = Integer.valueOf(buildIntegerValue(
                    PROPERTY_MAX_ATTRIBUTE_SIZE, DEFAULT_MAX_ATTRIBUTE_SIZE)
                );
                xif.setProperty(P_MAX_ATTRIBUTE_SIZE, maxAttributeSize);
                if (LOGGER.isLoggable(Level.FINE)) {
                    LOGGER.log(Level.FINE, P_MAX_ATTRIBUTE_SIZE + " is {0}", maxAttributeSize);
                }
            }

            if (xif.isPropertySupported(P_MAX_CHILDREN_PER_ELEMENT)) {
                maxChildrenPerElement = Integer.valueOf(buildIntegerValue(
                    PROPERTY_MAX_CHILDREN_PER_ELEMENT, DEFAULT_MAX_CHILDREN_PER_ELEMENT)
                );
                xif.setProperty(P_MAX_CHILDREN_PER_ELEMENT, maxChildrenPerElement);
                if (LOGGER.isLoggable(Level.FINE)) {
                    LOGGER.log(Level.FINE, P_MAX_CHILDREN_PER_ELEMENT + " is {0}", maxChildrenPerElement);
                }
            }

            if (xif.isPropertySupported(P_MAX_ELEMENT_DEPTH)) {
                maxElementDepth = Integer.valueOf(buildIntegerValue(
                    PROPERTY_MAX_ELEMENT_DEPTH, DEFAULT_MAX_ELEMENT_DEPTH)
                );
                xif.setProperty(P_MAX_ELEMENT_DEPTH, maxElementDepth);
                if (LOGGER.isLoggable(Level.FINE)) {
                    LOGGER.log(Level.FINE, P_MAX_ELEMENT_DEPTH + " is {0}", maxElementDepth);
                }
            }

            if (xif.isPropertySupported(P_MAX_ELEMENT_COUNT)) {
                maxElementCount = Long.valueOf(buildLongValue(
                    PROPERTY_MAX_ELEMENT_COUNT, DEFAULT_MAX_ELEMENT_COUNT)
                );
                xif.setProperty(P_MAX_ELEMENT_COUNT, maxElementCount);
                if (LOGGER.isLoggable(Level.FINE)) {
                    LOGGER.log(Level.FINE, P_MAX_ELEMENT_COUNT + " is {0}", maxElementCount);
                }
            }

            if (xif.isPropertySupported(P_MAX_CHARACTERS)) {
                maxCharacters = Long.valueOf(buildLongValue(
                    PROPERTY_MAX_CHARACTERS, DEFAULT_MAX_CHARACTERS)
                );
                xif.setProperty(P_MAX_CHARACTERS, maxCharacters);
                if (LOGGER.isLoggable(Level.FINE)) {
                    LOGGER.log(Level.FINE, P_MAX_CHARACTERS + " is {0}", maxCharacters);
                }
            }
            //Using try/catch instead of isPropertySupported because Woodstox
            //isPropertySupported is not always reliable
            try {
                //this is needed to make sure Woodstox behavior is spec compliant for
                //calls to XMLStreamReader.getNamespacePrefix
                xif.setProperty(P_RETURN_NULL_FOR_DEFAULT_NAMESPACE, Boolean.TRUE);
                if (LOGGER.isLoggable(Level.FINE)) {
                    LOGGER.log(Level.FINE, P_RETURN_NULL_FOR_DEFAULT_NAMESPACE + " is {0}", xif.getProperty(P_RETURN_NULL_FOR_DEFAULT_NAMESPACE));
                }
            } catch (Throwable t) {
                //ignore - this should not happen Woodstox 4.1.2 or later (maybe older version of Woodstox).
                LOGGER.log(Level.WARNING, "Expected property not found in Woodstox input factory: '{0}'", P_RETURN_NULL_FOR_DEFAULT_NAMESPACE);
            }
        }

        @Override
        public XMLStreamReader doCreate(String systemId, InputStream in, boolean rejectDTDs) {
            return super.doCreate(systemId, in, rejectDTDs);
        }

        @Override
        public XMLStreamReader doCreate(String systemId, Reader in, boolean rejectDTDs) {
            return super.doCreate(systemId, in, rejectDTDs);
        }
    }

    private static int buildIntegerValue(String propertyName, int defaultValue) {
        String propVal = System.getProperty(propertyName);
        if (propVal != null && propVal.length() > 0) {
            try {
                Integer value = Integer.parseInt(propVal);
                if (value > 0) {
                    // return with the value in System property
                    return value;
                }
            } catch (NumberFormatException nfe) {
                if (LOGGER.isLoggable(Level.WARNING)) {
                    LOGGER.log(Level.WARNING, StreamingMessages.INVALID_PROPERTY_VALUE_INTEGER(propertyName, propVal, Integer.toString(defaultValue)), nfe);
                }
            }
        }
        // return with the default value
        return defaultValue;
    }

    private static long buildLongValue(String propertyName, long defaultValue) {
        String propVal = System.getProperty(propertyName);
        if (propVal != null && propVal.length() > 0) {
            try {
                long value = Long.parseLong(propVal);
                if (value > 0L) {
                    // return with the value in System property
                    return value;
                }
            } catch (NumberFormatException nfe) {
                // defult will be returned
                if (LOGGER.isLoggable(Level.WARNING)) {
                    LOGGER.log(Level.WARNING, StreamingMessages.INVALID_PROPERTY_VALUE_LONG(propertyName, propVal, Long.toString(defaultValue)), nfe);
                }
            }
        }
        // return with the default value
        return defaultValue;
    }

    private static Boolean getProperty(final String prop) {
        return AccessController.doPrivileged(
            new java.security.PrivilegedAction<Boolean>() {
                @Override
                public Boolean run() {
                    String value = System.getProperty(prop);
                    return value != null ? Boolean.valueOf(value) : Boolean.FALSE;
                }
            }
        );
    }

}
/

java/ 10/ java.xml.ws/com/sun/xml/internal/ws/api/streaming/XMLStreamReaderFactory.java
