package org.apache.maven.surefire.booter;
   
   /*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you under the Apache License, Version 2.0 (the
    * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied.  See the License for the
   * specific language governing permissions and limitations
   * under the License.
   */
  
  import java.io.File;
  import java.net.MalformedURLException;
  import java.net.URL;
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.Iterator;
  import java.util.List;
  import org.apache.maven.surefire.util.UrlUtils;
  
  /**
   * An ordered list of classpath elements with set behaviour
   *
   * @author Kristian Rosenvold
   */
  public class Classpath
  {
      private static final JdkReflector jdkReflector = new JdkReflector();
  
      public static Classpath join( Classpath firstClasspath, Classpath secondClasspath )
      {
          Classpath joinedClasspath = new Classpath();
          joinedClasspath.addElementsOfClasspath( firstClasspath );
          joinedClasspath.addElementsOfClasspath( secondClasspath );
          return joinedClasspath;
      }
  
      private final List elements;
  
      public Classpath()
      {
          this.elements = new ArrayList();
      }
  
      public Classpath( Classpath other )
      {
          this.elements = new ArrayList( other.elements );
      }
  
      public Classpath( List elements )
      {
          this();
          addElements( elements );
      }
  
      public void addClassPathElementUrl( String path )
      {
          if ( path == null )
          {
              throw new IllegalArgumentException( "Null is not a valid class path element url." );
          }
          else if ( !elements.contains( path ) )
          {
              elements.add( path );
          }
      }
  
      private void addElements( List additionalElements )
      {
          for ( Iterator it = additionalElements.iterator(); it.hasNext(); )
          {
              String element = (String) it.next();
              addClassPathElementUrl( element );
          }
      }
  
      private void addElementsOfClasspath( Classpath otherClasspath )
      {
          if ( otherClasspath != null )
          {
              addElements( otherClasspath.elements );
          }
      }
  
      public List getClassPath()
      {
          return Collections.unmodifiableList( elements );
      }
  
     public List getAsUrlList()
         throws MalformedURLException
     {
         List urls = new ArrayList();
         for ( Iterator i = elements.iterator(); i.hasNext(); )
         {
             String url = (String) i.next();
             File f = new File( url );
             urls.add( UrlUtils.getURL( f ) );
         }
         return urls;
     }
 
     public void writeToSystemProperty( String propertyName )
     {
         StringBuffer sb = new StringBuffer();
         for ( Iterator i = elements.iterator(); i.hasNext(); )
         {
             sb.append( (String) i.next() ).append( File.pathSeparatorChar );
         }
         System.setProperty( propertyName, sb.toString() );
     }
 
     public boolean equals( Object o )
     {
         if ( this == o )
         {
             return true;
         }
         if ( o == null || getClass() != o.getClass() )
         {
             return false;
         }
 
         Classpath classpath = (Classpath) o;
 
         return !( elements != null ? !elements.equals( classpath.elements ) : classpath.elements != null );
 
     }
 
     public ClassLoader createClassLoader( ClassLoader parent, boolean childDelegation, boolean enableAssertions,
                                           String roleName )
         throws SurefireExecutionException
     {
         try
         {
             List urls = getAsUrlList();
             IsolatedClassLoader classLoader = new IsolatedClassLoader( parent, childDelegation, roleName );
             for ( Iterator iter = urls.iterator(); iter.hasNext(); )
             {
                 URL url = (URL) iter.next();
                 classLoader.addURL( url );
             }
             if ( parent != null )
             {
                 jdkReflector.invokeAssertionStatusMethod( parent, enableAssertions );
             }
             jdkReflector.invokeAssertionStatusMethod( classLoader, enableAssertions );
             return classLoader;
         }
         catch ( MalformedURLException e )
         {
             throw new SurefireExecutionException( "When creating classloader", e );
         }
     }
 
 
     public int hashCode()
     {
         return elements != null ? elements.hashCode() : 0;
     }
 }