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Diffstat (limited to 'sandbox/ant/sca/branches/tb7/modules/databinding-jaxb/src/main/java/org/apache/tuscany/sca/databinding/jaxb/JAXBContextCache.java')
-rw-r--r-- | sandbox/ant/sca/branches/tb7/modules/databinding-jaxb/src/main/java/org/apache/tuscany/sca/databinding/jaxb/JAXBContextCache.java | 448 |
1 files changed, 448 insertions, 0 deletions
diff --git a/sandbox/ant/sca/branches/tb7/modules/databinding-jaxb/src/main/java/org/apache/tuscany/sca/databinding/jaxb/JAXBContextCache.java b/sandbox/ant/sca/branches/tb7/modules/databinding-jaxb/src/main/java/org/apache/tuscany/sca/databinding/jaxb/JAXBContextCache.java new file mode 100644 index 0000000000..d616b9328e --- /dev/null +++ b/sandbox/ant/sca/branches/tb7/modules/databinding-jaxb/src/main/java/org/apache/tuscany/sca/databinding/jaxb/JAXBContextCache.java @@ -0,0 +1,448 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, + * software distributed under the License 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 org.apache.tuscany.sca.databinding.jaxb; + +import java.awt.Image; +import java.lang.ref.SoftReference; +import java.net.URI; +import java.security.AccessController; +import java.security.PrivilegedActionException; +import java.security.PrivilegedExceptionAction; +import java.util.ArrayList; +import java.util.Arrays; +import java.util.Calendar; +import java.util.Date; +import java.util.HashMap; +import java.util.HashSet; +import java.util.Iterator; +import java.util.List; +import java.util.Map; +import java.util.Set; +import java.util.UUID; +import java.util.concurrent.ConcurrentHashMap; + +import javax.activation.DataHandler; +import javax.xml.bind.JAXBContext; +import javax.xml.bind.JAXBException; +import javax.xml.bind.Marshaller; +import javax.xml.bind.Unmarshaller; +import javax.xml.transform.Source; + +import org.apache.tuscany.sca.databinding.util.LRUCache; + +/** + * @version $Rev$ $Date$ + */ +public class JAXBContextCache { + private static final int CACHE_SIZE = 128; + + private static HashMap<String, Class<?>> loadClassMap = new HashMap<String, Class<?>>(); + + static { + loadClassMap.put("byte", byte.class); + loadClassMap.put("int", int.class); + loadClassMap.put("short", short.class); + loadClassMap.put("long", long.class); + loadClassMap.put("float", float.class); + loadClassMap.put("double", double.class); + loadClassMap.put("boolean", boolean.class); + loadClassMap.put("char", char.class); + loadClassMap.put("void", void.class); + } + + protected static Class<?>[] JAXB_BUILTIN_CLASSES = + {byte[].class, boolean.class, byte.class, char.class, double.class, float.class, int.class, long.class, + short.class, void.class, java.awt.Image.class, java.io.File.class, java.lang.Boolean.class, + java.lang.Byte.class, java.lang.Character.class, java.lang.Class.class, java.lang.Double.class, + java.lang.Float.class, java.lang.Integer.class, java.lang.Long.class, java.lang.Object.class, + java.lang.Short.class, java.lang.String.class, java.lang.Void.class, java.math.BigDecimal.class, + java.math.BigInteger.class, java.net.URI.class, java.net.URL.class, java.util.Calendar.class, + java.util.Date.class, java.util.GregorianCalendar.class, java.util.UUID.class, + javax.activation.DataHandler.class, javax.xml.bind.JAXBElement.class, javax.xml.datatype.Duration.class, + javax.xml.datatype.XMLGregorianCalendar.class, javax.xml.namespace.QName.class, + javax.xml.transform.Source.class}; + + protected static final Set<Class<?>> BUILTIN_CLASSES_SET = new HashSet<Class<?>>(Arrays.asList(JAXB_BUILTIN_CLASSES)); + + /* + protected static Class<?>[] COMMON_ARRAY_CLASSES = + new Class[] {char[].class, short[].class, int[].class, long[].class, float[].class, double[].class, + String[].class + }; + + protected static final Set<Class<?>> COMMON_CLASSES_SET = new HashSet<Class<?>>(Arrays.asList(COMMON_ARRAY_CLASSES)); + */ + + protected LRUCache<Object, JAXBContext> cache; + protected Pool<JAXBContext, Marshaller> mpool; + protected Pool<JAXBContext, Unmarshaller> upool; + + // protected JAXBContext commonContext; + protected JAXBContext defaultContext; + + public JAXBContextCache() { + this(CACHE_SIZE, CACHE_SIZE, CACHE_SIZE); + } + + public JAXBContextCache(int contextSize, int marshallerSize, int unmarshallerSize) { + cache = new LRUCache<Object, JAXBContext>(contextSize); + mpool = new Pool<JAXBContext, Marshaller>(); + upool = new Pool<JAXBContext, Unmarshaller>(); + defaultContext = getDefaultJAXBContext(); + } + + private static JAXBContext newJAXBContext(final Class<?>... classesToBeBound) throws JAXBException { + try { + return AccessController.doPrivileged(new PrivilegedExceptionAction<JAXBContext>() { + public JAXBContext run() throws JAXBException { + return JAXBContext.newInstance(classesToBeBound); + } + }); + } catch (PrivilegedActionException e) { + throw (JAXBException)e.getException(); + } + } + + private static JAXBContext newJAXBContext(final String contextPath, final ClassLoader classLoader) + throws JAXBException { + try { + return AccessController.doPrivileged(new PrivilegedExceptionAction<JAXBContext>() { + public JAXBContext run() throws JAXBException { + return JAXBContext.newInstance(contextPath, classLoader); + } + }); + } catch (PrivilegedActionException e) { + throw (JAXBException)e.getException(); + } + } + + public static JAXBContext getDefaultJAXBContext() { + try { + return newJAXBContext(); + } catch (JAXBException e) { + throw new IllegalArgumentException(e); + } + } + + /** + * @param name of primitive type + * @return primitive Class or null + */ + public static Class<?> getPrimitiveClass(String text) { + return loadClassMap.get(text); + } + + /** + * Return the class for this name + * + * @return Class + */ + private static Class<?> forName(final String className, final boolean initialize, final ClassLoader classloader) + throws ClassNotFoundException { + // NOTE: This method must remain private because it uses AccessController + Class<?> cl = null; + try { + cl = AccessController.doPrivileged(new PrivilegedExceptionAction<Class<?>>() { + public Class<?> run() throws ClassNotFoundException { + // Class.forName does not support primitives + Class<?> cls = getPrimitiveClass(className); + if (cls == null) { + cls = Class.forName(className, initialize, classloader); + } + return cls; + } + }); + } catch (PrivilegedActionException e) { + throw (ClassNotFoundException)e.getException(); + } + + return cl; + } + + /** + * @param p Package + * @param cl + * @return true if each package has a ObjectFactory class or package-info + */ + public static boolean checkPackage(String p, ClassLoader cl) { + + // Each package must have an ObjectFactory + try { + Class<?> cls = forName(p + ".ObjectFactory", false, cl); + if (cls != null) { + return true; + } + //Catch Throwable as ClassLoader can throw an NoClassDefFoundError that + //does not extend Exception. So we will absorb any Throwable exception here. + } catch (Throwable e) { + // Ignore + } + + // [rfeng] If no ObjectFactory or jaxb.index is present, JAXBContext.newInstance(contextPath, classloader) + // will fail + /* + try { + Class<?> cls = forName(p + ".package-info", false, cl); + if (cls != null) { + return cls.isAnnotationPresent(XmlSchema.class); + } + //Catch Throwable as ClassLoader can throw an NoClassDefFoundError that + //does not extend Exception. So we will absorb any Throwable exception here. + } catch (Throwable e) { + // Ignore + } + */ + + return false; + } + + public Marshaller getMarshaller(JAXBContext context) throws JAXBException { + Marshaller marshaller = mpool.get(context); + if (marshaller == null) { + marshaller = context.createMarshaller(); + } + marshaller.setProperty(Marshaller.JAXB_FRAGMENT, Boolean.TRUE); + return marshaller; + } + + public void releaseJAXBMarshaller(JAXBContext context, Marshaller marshaller) { + if (marshaller != null) { + marshaller.setAttachmentMarshaller(null); + mpool.put(context, marshaller); + // No point unsetting marshaller's JAXB_FRAGMENT property, since we'll just reset it when + // doing the next get. + } + } + + public Unmarshaller getUnmarshaller(JAXBContext context) throws JAXBException { + Unmarshaller unmarshaller = upool.get(context); + if (unmarshaller == null) { + unmarshaller = context.createUnmarshaller(); + } + return unmarshaller; + } + + public void releaseJAXBUnmarshaller(JAXBContext context, Unmarshaller unmarshaller) { + if (unmarshaller != null) { + unmarshaller.setAttachmentUnmarshaller(null); + upool.put(context, unmarshaller); + } + } + + public LRUCache<Object, JAXBContext> getCache() { + return cache; + } + + public JAXBContext getJAXBContext(Class<?> cls) throws JAXBException { + if (BUILTIN_CLASSES_SET.contains(cls)) { + return defaultContext; + } + synchronized (cache) { + JAXBContext context = cache.get(cls); + if (context != null) { + return context; + } + Package pkg = cls.getPackage(); + if (pkg != null) { + context = cache.get(pkg); + if (context != null) { + return context; + } + } + + if (pkg != null && checkPackage(pkg.getName(), cls.getClassLoader())) { + context = newJAXBContext(pkg.getName(), cls.getClassLoader()); + cache.put(pkg, context); + } else { + context = newJAXBContext(cls); + cache.put(cls, context); + } + return context; + + } + } + + public JAXBContext getJAXBContext(Class<?>[] classes) throws JAXBException { + Set<Class<?>> classSet = new HashSet<Class<?>>(Arrays.asList(classes)); + return getJAXBContext(classSet); + } + + public JAXBContext getJAXBContext(Set<Class<?>> classes) throws JAXBException { + // Remove the JAXB built-in types to maximize the cache hit + Set<Class<?>> classSet = new HashSet<Class<?>>(classes); + classSet.removeAll(BUILTIN_CLASSES_SET); + + // FIXME: [rfeng] Remove java classes that are mapped to the same XSD type to avoid + // conflicts + if (classSet.contains(Date[].class)) { + classSet.remove(Calendar[].class); + } + + if (classSet.contains(URI[].class)) { + classSet.remove(UUID[].class); + } + + if (classSet.contains(Source[].class)) { + classSet.remove(Image[].class); + classSet.remove(DataHandler[].class); + } + + if(classSet.isEmpty()) { + return defaultContext; + } + + // For single class + if (classSet.size() == 1) { + return getJAXBContext(classSet.iterator().next()); + } + synchronized (cache) { + JAXBContext context = cache.get(classSet); + if (context != null) { + return context; + } + context = newJAXBContext(classSet.toArray(new Class<?>[classSet.size()])); + cache.put(classSet, context); + return context; + } + } + + public void clear() { + synchronized (cache) { + cache.clear(); + } + /* + synchronized (upool) { + upool.clear(); + } + synchronized (upool) { + upool.clear(); + } + */ + } + + // + // This inner class is copied in its entirety from the Axis2 utility class, + // org.apache.axis2.jaxws.message.databinding.JAXBUtils. We could look into extending but it's such a basic data structure + // without other dependencies so we might be better off copying it and avoiding a new + // Axis2 dependency here. + // + + /** + * Pool a list of items for a specific key + * + * @param <K> Key + * @param <V> Pooled object + */ + private static class Pool<K,V> { + private SoftReference<Map<K,List<V>>> softMap = + new SoftReference<Map<K,List<V>>>( + new ConcurrentHashMap<K, List<V>>()); + + // The maps are freed up when a LOAD FACTOR is hit + private static final int MAX_LIST_FACTOR = 50; + private static final int MAX_LOAD_FACTOR = 32; // Maximum number of JAXBContext to store + + /** + * @param key + * @return removed item from pool or null. + */ + public V get(K key) { + List<V> values = getValues(key); + synchronized (values) { + if (values.size()>0) { + V v = values.remove(values.size()-1); + return v; + + } + } + return null; + } + + /** + * Add item back to pool + * @param key + * @param value + */ + public void put(K key, V value) { + adjustSize(); + List<V> values = getValues(key); + synchronized (values) { + if (values.size() < MAX_LIST_FACTOR) { + values.add(value); + } + } + } + + /** + * Get or create a list of the values for the key + * @param key + * @return list of values. + */ + private List<V> getValues(K key) { + Map<K,List<V>> map = softMap.get(); + List<V> values = null; + if (map != null) { + values = map.get(key); + if(values !=null) { + return values; + } + } + synchronized (this) { + if (map != null) { + values = map.get(key); + } + if (values == null) { + if (map == null) { + map = new ConcurrentHashMap<K, List<V>>(); + softMap = + new SoftReference<Map<K,List<V>>>(map); + } + values = new ArrayList<V>(); + map.put(key, values); + + } + return values; + } + } + + /** + * AdjustSize + * When the number of keys exceeds the maximum load, half + * of the entries are deleted. + * + * The assumption is that the JAXBContexts, UnMarshallers, Marshallers, etc. require + * a large footprint. + */ + private void adjustSize() { + Map<K,List<V>> map = softMap.get(); + if (map != null && map.size() > MAX_LOAD_FACTOR) { + // Remove every other Entry in the map. + Iterator it = map.entrySet().iterator(); + boolean removeIt = false; + while (it.hasNext()) { + it.next(); + if (removeIt) { + it.remove(); + } + removeIt = !removeIt; + } + } + } + } +} |