Coverage Report - de.smartics.properties.spi.core.util.ClassLoaderUtils
 
Classes in this File Line Coverage Branch Coverage Complexity
ClassLoaderUtils
0%
0/15
0%
0/2
1.5
 
 1  
 /*
 2  
  * Copyright 2012-2013 smartics, Kronseder & Reiner GmbH
 3  
  *
 4  
  * Licensed under the Apache License, Version 2.0 (the "License");
 5  
  * you may not use this file except in compliance with the License.
 6  
  * You may obtain a copy of the License at
 7  
  *
 8  
  *     http://www.apache.org/licenses/LICENSE-2.0
 9  
  *
 10  
  * Unless required by applicable law or agreed to in writing, software
 11  
  * distributed under the License is distributed on an "AS IS" BASIS,
 12  
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 13  
  * See the License for the specific language governing permissions and
 14  
  * limitations under the License.
 15  
  */
 16  
 package de.smartics.properties.spi.core.util;
 17  
 
 18  
 import java.net.URL;
 19  
 
 20  
 import de.smartics.util.lang.classpath.ClassPathContext;
 21  
 
 22  
 /**
 23  
  * Utilities dealing with class loaders.
 24  
  */
 25  
 public final class ClassLoaderUtils
 26  
 {
 27  
   // ********************************* Fields *********************************
 28  
 
 29  
   // --- constants ------------------------------------------------------------
 30  
 
 31  
   // --- members --------------------------------------------------------------
 32  
 
 33  
   // ****************************** Initializer *******************************
 34  
 
 35  
   // ****************************** Constructors ******************************
 36  
 
 37  
   private ClassLoaderUtils()
 38  0
   {
 39  0
   }
 40  
 
 41  
   // ****************************** Inner Classes *****************************
 42  
 
 43  
   // ********************************* Methods ********************************
 44  
 
 45  
   // --- init -----------------------------------------------------------------
 46  
 
 47  
   // --- get&set --------------------------------------------------------------
 48  
 
 49  
   // --- business -------------------------------------------------------------
 50  
 
 51  
   /**
 52  
    * Determines the path to the class loader root that contains the given
 53  
    * {@code type}.
 54  
    *
 55  
    * @param type the type whose class loader root is requested.
 56  
    * @return the class loader root.
 57  
    * @throws NullPointerException if {@code type} is <code>null</code>.
 58  
    */
 59  
   public static String calcArchivePath(final Class<?> type)
 60  
     throws NullPointerException
 61  
   {
 62  0
     final ClassLoader loader = type.getClassLoader();
 63  0
     final String resource = type.getName().replace('.', '/') + ".class";
 64  0
     final String path = calcFirstArchivePath(loader, resource);
 65  0
     return path;
 66  
   }
 67  
 
 68  
   /**
 69  
    * Determines the path to the class loader root that contains the given
 70  
    * {@code resource}. The first matching path is returned. This call does not
 71  
    * check if there is more than one path that serves the given {@code resource}
 72  
    * .
 73  
    *
 74  
    * @param loader the loader to load the resource.
 75  
    * @param resource the resource whose class loader root is requested.
 76  
    * @return the class loader root for the given {@code resource}.
 77  
    * @throws NullPointerException if {@code loader} or {@code resource} is
 78  
    *           <code>null</code>.
 79  
    * @throws IllegalArgumentException if the resource cannot be found by the
 80  
    *           given class loader.
 81  
    */
 82  
   public static String calcFirstArchivePath(final ClassLoader loader,
 83  
       final String resource) throws NullPointerException,
 84  
     IllegalArgumentException
 85  
   {
 86  0
     final URL url = loader.getResource(resource);
 87  0
     if (url == null)
 88  
     {
 89  0
       throw new IllegalArgumentException(
 90  
           "The resource '" + resource
 91  
               + "' cannot be found by the given class loader.");
 92  
     }
 93  0
     final String urlString = url.toExternalForm();
 94  0
     final int endIndex = urlString.length() - resource.length();
 95  0
     final String path = urlString.substring(0, endIndex);
 96  0
     return path;
 97  
   }
 98  
 
 99  
   /**
 100  
    * Creates the class path context for the given class loader and its derived
 101  
    * context root. The first matching path is used to calculate the class path
 102  
    * root. This call does not check if there is more than one path that serves
 103  
    * the given {@code resource}.
 104  
    *
 105  
    * @param classLoader the class loader to access resources.
 106  
    * @param resource the resource whose class loader root is requested.
 107  
    * @return the class path context.
 108  
    */
 109  
   public static ClassPathContext createClassPathContext(
 110  
       final ClassLoader classLoader, final String resource)
 111  
   {
 112  0
     final String root = calcFirstArchivePath(classLoader, resource);
 113  0
     return new ClassPathContext(classLoader, root);
 114  
   }
 115  
 
 116  
   // --- object basics --------------------------------------------------------
 117  
 
 118  
 }