|
|||||||||||||||||||
| Source file | Conditionals | Statements | Methods | TOTAL | |||||||||||||||
| PerThreadSingleton.java | 100% | 73,3% | 75% | 76,2% |
|
||||||||||||||
| 1 | /* | |
| 2 | * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved. | |
| 3 | * | |
| 4 | * This software is open source. | |
| 5 | * See the bottom of this file for the licence. | |
| 6 | */ | |
| 7 | ||
| 8 | package org.dom4j.util; | |
| 9 | ||
| 10 | import java.lang.ref.WeakReference; | |
| 11 | ||
| 12 | /** | |
| 13 | * <p> | |
| 14 | * <code>PerThreadSingleton</code> is an implementation of the | |
| 15 | * SingletonStrategy used to provide common factory access to a single object | |
| 16 | * instance based on an implementation strategy for one object instance per | |
| 17 | * thread. This is useful in replace of the ThreadLocal usage. | |
| 18 | * </p> | |
| 19 | * | |
| 20 | * @author <a href="mailto:ddlucas@users.sourceforge.net">David Lucas </a> | |
| 21 | * @version $Revision: 1.3 $ | |
| 22 | */ | |
| 23 | ||
| 24 | public class PerThreadSingleton implements SingletonStrategy { | |
| 25 | private String singletonClassName = null; | |
| 26 | ||
| 27 | private ThreadLocal perThreadCache = new ThreadLocal(); | |
| 28 | ||
| 29 | 2 | public PerThreadSingleton() { |
| 30 | } | |
| 31 | ||
| 32 | 0 | public void reset() { |
| 33 | 0 | perThreadCache = new ThreadLocal(); |
| 34 | } | |
| 35 | ||
| 36 | 1003 | public Object instance() { |
| 37 | 1003 | Object singletonInstancePerThread = null; |
| 38 | // use weak reference to prevent cyclic reference during GC | |
| 39 | 1003 | WeakReference ref = (WeakReference) perThreadCache.get(); |
| 40 | // singletonInstancePerThread=perThreadCache.get(); | |
| 41 | // if (singletonInstancePerThread==null) { | |
| 42 | 1003 | if (ref == null || ref.get() == null) { |
| 43 | 6 | Class clazz = null; |
| 44 | 6 | try { |
| 45 | 6 | clazz = Thread.currentThread().getContextClassLoader().loadClass( |
| 46 | singletonClassName); | |
| 47 | 6 | singletonInstancePerThread = clazz.newInstance(); |
| 48 | } catch (Exception ignore) { | |
| 49 | 0 | try { |
| 50 | 0 | clazz = Class.forName(singletonClassName); |
| 51 | 0 | singletonInstancePerThread = clazz.newInstance(); |
| 52 | } catch (Exception ignore2) { | |
| 53 | } | |
| 54 | } | |
| 55 | 6 | perThreadCache.set(new WeakReference(singletonInstancePerThread)); |
| 56 | } else { | |
| 57 | 997 | singletonInstancePerThread = ref.get(); |
| 58 | } | |
| 59 | 1003 | return singletonInstancePerThread; |
| 60 | } | |
| 61 | ||
| 62 | 2 | public void setSingletonClassName(String singletonClassName) { |
| 63 | 2 | this.singletonClassName = singletonClassName; |
| 64 | } | |
| 65 | ||
| 66 | } | |
| 67 | ||
| 68 | /* | |
| 69 | * Redistribution and use of this software and associated documentation | |
| 70 | * ("Software"), with or without modification, are permitted provided that the | |
| 71 | * following conditions are met: | |
| 72 | * | |
| 73 | * 1. Redistributions of source code must retain copyright statements and | |
| 74 | * notices. Redistributions must also contain a copy of this document. | |
| 75 | * | |
| 76 | * 2. Redistributions in binary form must reproduce the above copyright notice, | |
| 77 | * this list of conditions and the following disclaimer in the documentation | |
| 78 | * and/or other materials provided with the distribution. | |
| 79 | * | |
| 80 | * 3. The name "DOM4J" must not be used to endorse or promote products derived | |
| 81 | * from this Software without prior written permission of MetaStuff, Ltd. For | |
| 82 | * written permission, please contact dom4j-info@metastuff.com. | |
| 83 | * | |
| 84 | * 4. Products derived from this Software may not be called "DOM4J" nor may | |
| 85 | * "DOM4J" appear in their names without prior written permission of MetaStuff, | |
| 86 | * Ltd. DOM4J is a registered trademark of MetaStuff, Ltd. | |
| 87 | * | |
| 88 | * 5. Due credit should be given to the DOM4J Project - http://www.dom4j.org | |
| 89 | * | |
| 90 | * THIS SOFTWARE IS PROVIDED BY METASTUFF, LTD. AND CONTRIBUTORS ``AS IS'' AND | |
| 91 | * ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
| 92 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
| 93 | * ARE DISCLAIMED. IN NO EVENT SHALL METASTUFF, LTD. OR ITS CONTRIBUTORS BE | |
| 94 | * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR | |
| 95 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF | |
| 96 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS | |
| 97 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN | |
| 98 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) | |
| 99 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE | |
| 100 | * POSSIBILITY OF SUCH DAMAGE. | |
| 101 | * | |
| 102 | * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved. | |
| 103 | */ |
|
||||||||||