package org.codehaus.mojo.jaxb2.shared.environment;
   
   /*
    * 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 org.apache.maven.plugin.logging.Log;
  import org.codehaus.mojo.jaxb2.shared.Validate;
  import org.codehaus.mojo.jaxb2.shared.environment.classloading.ThreadContextClassLoaderBuilder;
  import org.codehaus.mojo.jaxb2.shared.environment.classloading.ThreadContextClassLoaderHolder;
  import org.codehaus.mojo.jaxb2.shared.environment.logging.LoggingHandlerEnvironmentFacet;
  
  import java.util.ArrayList;
  import java.util.List;
  
  /**
   * Compound EnvironmentFacet implementation which is used to set up and use a collection
   * of other EnvironmentFacet instances during the run of the JAXB2 Maven Plugin.
   *
   * @author <a href="mailto:lj@jguru.se">Lennart J&ouml;relid</a>, jGuru Europe AB
   */
  public class ToolExecutionEnvironment extends AbstractLogAwareFacet {
  
      // Internal state
      private ThreadContextClassLoaderBuilder builder;
      private ThreadContextClassLoaderHolder holder;
      private LoggingHandlerEnvironmentFacet loggingHandlerEnvironmentFacet;
      private List<EnvironmentFacet> extraFacets;
  
      /**
       * Creates a new ToolExecutionEnvironment object wrapping the supplied Maven Log.
       *
       * @param mavenLog            The active Maven Log.
       * @param builder             The ThreadContextClassLoaderBuilder used to set up a ThreadContext ClassLoader for
       *                            this tool execution environment.
       * @param loggingHandlerFacet The EnvironmentFacet for replacing Handlers from Java Util Logging with a Maven Log.
       */
      public ToolExecutionEnvironment(final Log mavenLog,
                                      final ThreadContextClassLoaderBuilder builder,
                                      final LoggingHandlerEnvironmentFacet loggingHandlerFacet) {
          super(mavenLog);
  
          // Check sanity
          Validate.notNull(builder, "builder");
          Validate.notNull(loggingHandlerFacet, "loggingHandlerFacet");
  
          // Assign internal state
          this.builder = builder;
          this.loggingHandlerEnvironmentFacet = loggingHandlerFacet;
          extraFacets = new ArrayList<EnvironmentFacet>();
      }
  
      /**
       * Adds the supplied EnvironmentFacet to this ToolExecutionEnvironment.
       *
       * @param facet the non-null EnvironmentFacet to add to this ToolExecutionEnvironment.
       */
      public void add(final EnvironmentFacet facet) {
  
          // Check sanity
          Validate.notNull(facet, "facet");
  
          // All done.
          extraFacets.add(facet);
      }
  
      /**
       * Delegate method retrieving the classpath as argument from the underlying ThreadContextClassLoaderHolder.
       * Note that the setup method must be invoked before this one is.
       *
       * @return the ClassPath as an argument to external processes such as XJC.
       * @see ThreadContextClassLoaderHolder#getClassPathAsArgument()
       */
      public String getClassPathAsArgument() {
  
          // Check sanity
          if (holder == null) {
              throw new IllegalStateException("Cannot retrieve the classpath argument before calling 'setup'");
          }
  
          // Delegate and return
          return holder.getClassPathAsArgument();
      }
  
     /**
      * {@inheritDoc}
      */
     @Override
     public final void setup() {
 
         // Setup mandatory environment facets
         try {
 
             if (log.isDebugEnabled()) {
                 log.debug("ToolExecutionEnvironment setup -- Starting.");
             }
 
             // Build the ClassLoader as required for the JAXB tools
             holder = builder.buildAndSet();
 
             // Redirect the JUL logging handler used by the tools to the Maven log.
             loggingHandlerEnvironmentFacet.setup();
 
             // Setup optional/extra environment facets
             for (EnvironmentFacet current : extraFacets) {
                 try {
                     current.setup();
                 } catch (Exception e) {
                     throw new IllegalStateException("Could not setup() EnvironmentFacet of type ["
                             + current.getClass().getName() + "]", e);
                 }
             }
 
             if (log.isDebugEnabled()) {
                 log.debug("ToolExecutionEnvironment setup -- Done.");
             }
 
         } catch (IllegalStateException e) {
             throw e;
         } catch (Exception e) {
             throw new IllegalStateException("Could not setup() mandatory EnvironmentFacets.", e);
         }
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public final void restore() {
 
         try {
 
             if (log.isDebugEnabled()) {
                 log.debug("ToolExecutionEnvironment restore -- Starting.");
             }
 
             for (EnvironmentFacet current : extraFacets) {
                 try {
                     current.restore();
                 } catch (Exception e) {
                     throw new IllegalStateException("Could not restore() EnvironmentFacet of type ["
                             + current.getClass().getName() + "]", e);
                 }
             }
         } finally {
 
             // Restore the logging handler structure.
             loggingHandlerEnvironmentFacet.restore();
 
             // Restore the original ClassLoader
             holder.restoreClassLoaderAndReleaseThread();
 
             if (log.isDebugEnabled()) {
                 log.debug("ToolExecutionEnvironment restore -- Done.");
             }
         }
     }
 }