Mercurial > jdk8-mips64-public > jaxws / file revision

 /*

  * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.

  * 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,

  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

  *

  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

  * or visit www.oracle.com if you need additional information or have any

  * questions.

  */

 package com.sun.xml.internal.bind.v2;

 import java.lang.reflect.Constructor;

 import java.lang.reflect.InvocationTargetException;

 import java.lang.reflect.Method;

 import java.lang.reflect.Modifier;

 import java.lang.ref.WeakReference;

 import java.util.Map;

 import java.util.WeakHashMap;

 import java.util.logging.Level;

 import java.util.logging.Logger;

 import com.sun.xml.internal.bind.Util;

 /**

  * Creates new instances of classes.

  *

  * <p>

  * This code handles the case where the class is not public or the constructor is

  * not public.

  *

  * @since 2.0

  * @author Kohsuke Kawaguchi

  */

 public final class ClassFactory {

     private static final Class[] emptyClass = new Class[0];

     private static final Object[] emptyObject = new Object[0];

     private static final Logger logger = Util.getClassLogger();

     /**

      * Cache from a class to its default constructor.

      *

      * To avoid synchronization among threads, we use {@link ThreadLocal}.

      */

     private static final ThreadLocal<Map<Class, WeakReference<Constructor>>> tls = new ThreadLocal<Map<Class,WeakReference<Constructor>>>() {

         @Override

         public Map<Class,WeakReference<Constructor>> initialValue() {

             return new WeakHashMap<Class,WeakReference<Constructor>>();

         }

     };

     public static void cleanCache() {

         if (tls != null) {

             try {

                 tls.remove();

             } catch (Exception e) {

                 logger.log(Level.WARNING, "Unable to clean Thread Local cache of classes used in Unmarshaller: {0}", e.getLocalizedMessage());

             }

         }

     }

     /**

      * Creates a new instance of the class but throw exceptions without catching it.

      */

     public static <T> T create0( final Class<T> clazz ) throws IllegalAccessException, InvocationTargetException, InstantiationException {

         Map<Class,WeakReference<Constructor>> m = tls.get();

         Constructor<T> cons = null;

         WeakReference<Constructor> consRef = m.get(clazz);

         if(consRef!=null)

             cons = consRef.get();

         if(cons==null) {

             try {

                 cons = clazz.getDeclaredConstructor(emptyClass);

             } catch (NoSuchMethodException e) {

                 logger.log(Level.INFO,"No default constructor found on "+clazz,e);

                 NoSuchMethodError exp;

                 if(clazz.getDeclaringClass()!=null && !Modifier.isStatic(clazz.getModifiers())) {

                     exp = new NoSuchMethodError(Messages.NO_DEFAULT_CONSTRUCTOR_IN_INNER_CLASS.format(clazz.getName()));

                 } else {

                     exp = new NoSuchMethodError(e.getMessage());

                 }

                 exp.initCause(e);

                 throw exp;

             }

             int classMod = clazz.getModifiers();

             if(!Modifier.isPublic(classMod) || !Modifier.isPublic(cons.getModifiers())) {

                 // attempt to make it work even if the constructor is not accessible

                 try {

                     cons.setAccessible(true);

                 } catch(SecurityException e) {

                     // but if we don't have a permission to do so, work gracefully.

                     logger.log(Level.FINE,"Unable to make the constructor of "+clazz+" accessible",e);

                     throw e;

                 }

             }

             m.put(clazz,new WeakReference<Constructor>(cons));

         }

         return cons.newInstance(emptyObject);

     }

     /**

      * The same as {@link #create0} but with an error handling to make

      * the instantiation error fatal.

      */

     public static <T> T create( Class<T> clazz ) {

         try {

             return create0(clazz);

         } catch (InstantiationException e) {

             logger.log(Level.INFO,"failed to create a new instance of "+clazz,e);

             throw new InstantiationError(e.toString());

         } catch (IllegalAccessException e) {

             logger.log(Level.INFO,"failed to create a new instance of "+clazz,e);

             throw new IllegalAccessError(e.toString());

         } catch (InvocationTargetException e) {

             Throwable target = e.getTargetException();

             // most likely an error on the user's code.

             // just let it through for the ease of debugging

             if(target instanceof RuntimeException)

                 throw (RuntimeException)target;

             // error. just forward it for the ease of debugging

             if(target instanceof Error)

                 throw (Error)target;

             // a checked exception.

             // not sure how we should report this error,

             // but for now we just forward it by wrapping it into a runtime exception

             throw new IllegalStateException(target);

         }

     }

     /**

      *  Call a method in the factory class to get the object.

      */

     public static Object create(Method method) {

         Throwable errorMsg;

         try {

             return method.invoke(null, emptyObject);

         } catch (InvocationTargetException ive) {

             Throwable target = ive.getTargetException();

             if(target instanceof RuntimeException)

                 throw (RuntimeException)target;

             if(target instanceof Error)

                 throw (Error)target;

             throw new IllegalStateException(target);

         } catch (IllegalAccessException e) {

             logger.log(Level.INFO,"failed to create a new instance of "+method.getReturnType().getName(),e);

             throw new IllegalAccessError(e.toString());

         } catch (IllegalArgumentException iae){

             logger.log(Level.INFO,"failed to create a new instance of "+method.getReturnType().getName(),iae);

             errorMsg = iae;

         } catch (NullPointerException npe){

             logger.log(Level.INFO,"failed to create a new instance of "+method.getReturnType().getName(),npe);

             errorMsg = npe;

         } catch (ExceptionInInitializerError eie){

             logger.log(Level.INFO,"failed to create a new instance of "+method.getReturnType().getName(),eie);

             errorMsg = eie;

         }

         NoSuchMethodError exp;

         exp = new NoSuchMethodError(errorMsg.getMessage());

         exp.initCause(errorMsg);

         throw exp;

     }

     /**

      * Infers the instanciable implementation class that can be assigned to the given field type.

      *

      * @return null

      *      if inference fails.

      */

     public static <T> Class<? extends T> inferImplClass(Class<T> fieldType, Class[] knownImplClasses) {

         if(!fieldType.isInterface())

             return fieldType;

         for( Class<?> impl : knownImplClasses ) {

             if(fieldType.isAssignableFrom(impl))

                 return impl.asSubclass(fieldType);

         }

         // if we can't find an implementation class,

         // let's just hope that we will never need to create a new object,

         // and returns null

         return null;

     }

 }