1 /*

     2  * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Oracle designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Oracle in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

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

    20  *

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

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

    23  * questions.

    24  */

    25 

    26 package com.sun.xml.internal.messaging.saaj.soap;

    27 

    28 import java.security.AccessController;

    29 import java.security.PrivilegedAction;

    30 import java.text.MessageFormat;

    31 import java.util.ResourceBundle;

    32 import java.util.WeakHashMap;

    33 

    34 /**

    35  * Simple utility ensuring that the value is cached only in case it is non-internal implementation

    36  */

    37 abstract class ContextClassloaderLocal<V> {

    38 

    39     private static final String FAILED_TO_CREATE_NEW_INSTANCE = "FAILED_TO_CREATE_NEW_INSTANCE";

    40 

    41     private WeakHashMap<ClassLoader, V> CACHE = new WeakHashMap<ClassLoader, V>();

    42 

    43     public V get() throws Error {

    44         ClassLoader tccl = getContextClassLoader();

    45         V instance = CACHE.get(tccl);

    46         if (instance == null) {

    47             instance = createNewInstance();

    48             CACHE.put(tccl, instance);

    49         }

    50         return instance;

    51     }

    52 

    53     public void set(V instance) {

    54         CACHE.put(getContextClassLoader(), instance);

    55     }

    56 

    57     protected abstract V initialValue() throws Exception;

    58 

    59     private V createNewInstance() {

    60         try {

    61             return initialValue();

    62         } catch (Exception e) {

    63             throw new Error(format(FAILED_TO_CREATE_NEW_INSTANCE, getClass().getName()), e);

    64         }

    65     }

    66 

    67     private static String format(String property, Object... args) {

    68         String text = ResourceBundle.getBundle(ContextClassloaderLocal.class.getName()).getString(property);

    69         return MessageFormat.format(text, args);

    70     }

    71 

    72     private static ClassLoader getContextClassLoader() {

    73         return (ClassLoader)

    74                 AccessController.doPrivileged(new PrivilegedAction() {

    75                     public Object run() {

    76                         ClassLoader cl = null;

    77                         try {

    78                             cl = Thread.currentThread().getContextClassLoader();

    79                         } catch (SecurityException ex) {

    80                         }

    81                         return cl;

    82                     }

    83                 });

    84     }

    85 }