com.sun.xml.ws.api.streaming.XMLStreamWriterFactory Maven / Gradle / Ivy
/*
* The contents of this file are subject to the terms
* of the Common Development and Distribution License
* (the License). You may not use this file except in
* compliance with the License.
*
* You can obtain a copy of the license at
* https://glassfish.dev.java.net/public/CDDLv1.0.html.
* See the License for the specific language governing
* permissions and limitations under the License.
*
* When distributing Covered Code, include this CDDL
* Header Notice in each file and include the License file
* at https://glassfish.dev.java.net/public/CDDLv1.0.html.
* If applicable, add the following below the CDDL Header,
* with the fields enclosed by brackets [] replaced by
* you own identifying information:
* "Portions Copyrighted [year] [name of copyright owner]"
*
* Copyright 2006 Sun Microsystems Inc. All Rights Reserved
*/
package com.sun.xml.ws.api.streaming;
import com.sun.istack.NotNull;
import com.sun.istack.Nullable;
import com.sun.xml.ws.streaming.XMLReaderException;
import javax.xml.stream.XMLOutputFactory;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamReader;
import javax.xml.stream.XMLStreamWriter;
import javax.xml.transform.stream.StreamResult;
import javax.xml.ws.WebServiceException;
import java.io.OutputStream;
import java.io.StringWriter;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
/**
* Factory for {@link XMLStreamWriter}.
*
*
* This wraps {@link XMLOutputFactory} and allows us to reuse {@link XMLStreamWriter} instances
* when appropriate.
*
* @author Kohsuke Kawaguchi
*/
public abstract class XMLStreamWriterFactory {
/**
* Singleton instance.
*/
private static volatile @NotNull XMLStreamWriterFactory theInstance;
static {
XMLOutputFactory xof = XMLOutputFactory.newInstance();
XMLStreamWriterFactory 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(!Boolean.getBoolean(XMLStreamWriterFactory.class.getName()+".noPool"))
f = Zephyr.newInstance(xof);
if(f==null)
f = new Default(xof);
theInstance = f;
}
/**
* See {@link #create(OutputStream)} for the contract.
* This method may be invoked concurrently.
*/
public abstract XMLStreamWriter doCreate(OutputStream out);
/**
* See {@link #create(OutputStream,String)} for the contract.
* This method may be invoked concurrently.
*/
public abstract XMLStreamWriter doCreate(OutputStream out, String encoding);
/**
* See {@link #recycle(XMLStreamWriter)} for the contract.
* This method may be invoked concurrently.
*/
public abstract void doRecycle(XMLStreamWriter r);
/**
* Should be invoked when the code finished using an {@link XMLStreamWriter}.
*
*
* If the recycled instance implements {@link RecycleAware},
* {@link 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 {@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.
*
*
* This method may be invked 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(XMLStreamWriter r) {
get().doRecycle(r);
}
/**
* Interface that can be implemented by {@link XMLStreamWriter} to
* be notified when it's recycled.
*
*
* This provides a filtering {@link XMLStreamWriter} an opportunity to
* recycle its inner {@link XMLStreamWriter}.
*/
public interface RecycleAware {
void onRecycled();
}
/**
* Gets the singleton instance.
*/
public static @NotNull XMLStreamWriterFactory get() {
return theInstance;
}
/**
* Overrides the singleton {@link XMLStreamWriterFactory} instance that
* the JAX-WS RI uses.
*
* @param f
* must not be null.
*/
public static void set(@NotNull XMLStreamWriterFactory f) {
if(f==null) throw new IllegalArgumentException();
theInstance = f;
}
/**
* Short-cut for {@link #create(OutputStream, String)} with UTF-8.
*/
public static XMLStreamWriter create(OutputStream out) {
return get().doCreate(out);
}
public static XMLStreamWriter create(OutputStream out, String encoding) {
return get().doCreate(out, encoding);
}
/**
* @deprecated
* Use {@link #create(OutputStream)}
*/
public static XMLStreamWriter createXMLStreamWriter(OutputStream out) {
return create(out);
}
/**
* @deprecated
* Use {@link #create(OutputStream, String)}
*/
public static XMLStreamWriter createXMLStreamWriter(OutputStream out, String encoding) {
return create(out, encoding);
}
/**
* @deprecated
* Use {@link #create(OutputStream, String)}. The boolean flag was unused anyway.
*/
public static XMLStreamWriter createXMLStreamWriter(OutputStream out, String encoding, boolean declare) {
return create(out,encoding);
}
/**
* Default {@link XMLStreamWriterFactory} implementation
* that can work with any {@link XMLOutputFactory}.
*
*
* {@link XMLOutputFactory} is not required to be thread-safe, so the
* create method on this implementation is synchronized.
*/
public static final class Default extends XMLStreamWriterFactory {
private final XMLOutputFactory xof;
public Default(XMLOutputFactory xof) {
this.xof = xof;
}
public XMLStreamWriter doCreate(OutputStream out) {
return doCreate(out,"UTF-8");
}
public synchronized XMLStreamWriter doCreate(OutputStream out, String encoding) {
try {
return xof.createXMLStreamWriter(out,encoding);
} catch (XMLStreamException e) {
throw new XMLReaderException("stax.cantCreate",e);
}
}
public void doRecycle(XMLStreamWriter r) {
// no recycling
}
}
/**
* {@link XMLStreamWriterFactory} implementation for Sun's StaX implementation.
*
*
* This implementation supports instance reuse.
*/
public static final class Zephyr extends XMLStreamWriterFactory {
private final XMLOutputFactory xof;
private final ThreadLocal pool = new ThreadLocal();
private final Method resetMethod;
private final Method setOutputMethod;
private final Class zephyrClass;
public static XMLStreamWriterFactory newInstance(XMLOutputFactory xof) {
try {
Class clazz = xof.createXMLStreamWriter(new StringWriter()).getClass();
if(!clazz.getName().startsWith("com.sun.xml.stream."))
return null; // nope
return new Zephyr(xof,clazz);
} catch (XMLStreamException e) {
return null; // impossible
} catch (NoSuchMethodException e) {
return null; // this xof wasn't Zephyr
}
}
private Zephyr(XMLOutputFactory xof, Class clazz) throws NoSuchMethodException {
this.xof = xof;
zephyrClass = clazz;
setOutputMethod = clazz.getMethod("setOutput", StreamResult.class, String.class);
resetMethod = clazz.getMethod("reset");
}
/**
* Fetchs an instance from the pool if available, otherwise null.
*/
private @Nullable XMLStreamWriter fetch() {
XMLStreamWriter sr = pool.get();
if(sr==null) return null;
pool.set(null);
return sr;
}
public XMLStreamWriter doCreate(OutputStream out) {
return doCreate(out,"UTF-8");
}
public XMLStreamWriter doCreate(OutputStream out, String encoding) {
XMLStreamWriter xsw = fetch();
if(xsw!=null) {
// try to reuse
try {
resetMethod.invoke(xsw);
setOutputMethod.invoke(xsw,new StreamResult(out),encoding);
return xsw;
} catch (IllegalAccessException e) {
throw new XMLReaderException("stax.cantCreate",e);
} catch (InvocationTargetException e) {
throw new XMLReaderException("stax.cantCreate",e);
}
}
// create a new instance
try {
return xof.createXMLStreamWriter(out,encoding);
} catch (XMLStreamException e) {
throw new XMLReaderException("stax.cantCreate",e);
}
}
public void doRecycle(XMLStreamWriter r) {
if(zephyrClass.isInstance(r)) {
// this flushes the underlying stream, so it might cause chunking issue
try {
r.close();
} catch (XMLStreamException e) {
throw new WebServiceException(e);
}
pool.set(r);
}
if(r instanceof RecycleAware)
((RecycleAware)r).onRecycled();
}
}
}