Coverage Report - org.codehaus.plexus.component.factory.java.JavaComponentFactory
 
Classes in this File Line Coverage Branch Coverage Complexity
JavaComponentFactory
41 %
10/24
50 %
3/6
5,667
 
 1  
 package org.codehaus.plexus.component.factory.java;
 2  
 
 3  
 /*
 4  
  * Copyright 2001-2006 Codehaus Foundation.
 5  
  *
 6  
  * Licensed under the Apache License, Version 2.0 (the "License");
 7  
  * you may not use this file except in compliance with the License.
 8  
  * You may obtain a copy of the License at
 9  
  *
 10  
  *      http://www.apache.org/licenses/LICENSE-2.0
 11  
  *
 12  
  * Unless required by applicable law or agreed to in writing, software
 13  
  * distributed under the License is distributed on an "AS IS" BASIS,
 14  
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 15  
  * See the License for the specific language governing permissions and
 16  
  * limitations under the License.
 17  
  */
 18  
 
 19  
 import org.codehaus.plexus.PlexusContainer;
 20  
 import org.codehaus.plexus.classworlds.realm.ClassRealm;
 21  
 import org.codehaus.plexus.component.factory.AbstractComponentFactory;
 22  
 import org.codehaus.plexus.component.factory.ComponentInstantiationException;
 23  
 import org.codehaus.plexus.component.repository.ComponentDescriptor;
 24  
 
 25  
 import java.lang.reflect.Modifier;
 26  
 
 27  
 /**
 28  
  * Component Factory for components written in Java Language which have default no parameter constructor
 29  
  *
 30  
  * @author Jason van Zyl
 31  
  * @author <a href="mailto:mmaczka@interia.pl">Michal Maczka</a>
 32  
  * @version $Id$
 33  
  */
 34  64
 public class JavaComponentFactory
 35  
     extends AbstractComponentFactory
 36  
 {
 37  
     public String getId()
 38  
     {
 39  0
         return "java";
 40  
     }
 41  
 
 42  
     public Object newInstance( ComponentDescriptor componentDescriptor,
 43  
                                ClassRealm classRealm,
 44  
                                PlexusContainer container )
 45  
         throws ComponentInstantiationException
 46  
     {
 47  3
         Class implementationClass = null;
 48  
 
 49  
         try
 50  
         {
 51  3
             String implementation = componentDescriptor.getImplementation();
 52  
 
 53  3
             implementationClass = classRealm.loadClass( implementation );
 54  
 
 55  3
             int modifiers = implementationClass.getModifiers();
 56  
 
 57  3
             if ( Modifier.isInterface( modifiers ) )
 58  
             {
 59  0
                 throw new ComponentInstantiationException(
 60  
                     "Cannot instantiate implementation '" + implementation + "' because the class is a interface." );
 61  
             }
 62  
 
 63  3
             if ( Modifier.isAbstract( modifiers ) )
 64  
             {
 65  1
                 throw new ComponentInstantiationException(
 66  
                     "Cannot instantiate implementation '" + implementation + "' because the class is abstract." );
 67  
             }
 68  
 
 69  2
             Object instance = implementationClass.newInstance();
 70  
 
 71  2
             return instance;
 72  
         }
 73  0
         catch ( InstantiationException e )
 74  
         {
 75  
             //PLXAPI: most probably cause of this is the implementation class not having
 76  
             //        a default constructor.
 77  0
             throw makeException( classRealm, componentDescriptor, implementationClass, e );
 78  
         }
 79  0
         catch ( ClassNotFoundException e )
 80  
         {
 81  0
             throw makeException( classRealm, componentDescriptor, implementationClass, e );
 82  
         }
 83  0
         catch ( IllegalAccessException e )
 84  
         {
 85  0
             throw makeException( classRealm, componentDescriptor, implementationClass, e );
 86  
         }
 87  0
         catch ( LinkageError e )
 88  
         {
 89  0
             throw makeException( classRealm, componentDescriptor, implementationClass, e );
 90  
         }
 91  
     }
 92  
 
 93  
     private ComponentInstantiationException makeException( ClassRealm componentClassRealm,
 94  
                                                            ComponentDescriptor componentDescriptor,
 95  
                                                            Class implementationClass,
 96  
                                                            Throwable e )
 97  
     {
 98  
         // ----------------------------------------------------------------------
 99  
         // Display the realm when there is an error, We should probably return a string here so we
 100  
         // can incorporate this into the error message for easy debugging.
 101  
         // ----------------------------------------------------------------------
 102  
 
 103  
         String msg;
 104  
 
 105  0
         if ( componentClassRealm == null )
 106  
         {
 107  0
             msg = "classRealm is null for " + componentDescriptor;
 108  
         }
 109  
         else
 110  
         {
 111  0
             msg = "Could not instantiate component: " + componentDescriptor.getHumanReadableKey() + " realm: "
 112  
                 + componentClassRealm.getId();
 113  
         }
 114  
 
 115  0
         return new ComponentInstantiationException( msg, e );
 116  
     }
 117  
 }