package org.apache.maven.plugins.pmd.exec;
   
   /*
    * 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.BufferedInputStream;
  import java.io.BufferedOutputStream;
  import java.io.File;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  import java.io.UnsupportedEncodingException;
  import java.net.URL;
  import java.net.URLClassLoader;
  import java.net.URLDecoder;
  import java.nio.charset.StandardCharsets;
  import java.util.logging.Handler;
  import java.util.logging.Level;
  import java.util.logging.SimpleFormatter;
  
  import org.apache.maven.cli.logging.Slf4jConfiguration;
  import org.apache.maven.cli.logging.Slf4jConfigurationFactory;
  import org.codehaus.plexus.logging.console.ConsoleLogger;
  import org.slf4j.ILoggerFactory;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import org.slf4j.bridge.SLF4JBridgeHandler;
  
  abstract class Executor
  {
      private static final Logger LOG = LoggerFactory.getLogger( Executor.class );
  
      /**
       * This holds a strong reference in case we configured the logger to
       * redirect to slf4j. See {@link #showPmdLog}. Without a strong reference,
       * the logger might be garbage collected and the redirect to slf4j is gone.
       */
      private java.util.logging.Logger julLogger;
  
      protected void setupPmdLogging( boolean showPmdLog, String logLevel )
      {
          if ( !showPmdLog )
          {
              return;
          }
  
          java.util.logging.Logger logger = java.util.logging.Logger.getLogger( "net.sourceforge.pmd" );
  
          boolean slf4jBridgeAlreadyAdded = false;
          for ( Handler handler : logger.getHandlers() )
          {
              if ( handler instanceof SLF4JBridgeHandler )
              {
                  slf4jBridgeAlreadyAdded = true;
                  break;
              }
          }
  
          if ( slf4jBridgeAlreadyAdded )
          {
              return;
          }
  
          SLF4JBridgeHandler handler = new SLF4JBridgeHandler();
          SimpleFormatter formatter = new SimpleFormatter();
          handler.setFormatter( formatter );
          logger.setUseParentHandlers( false );
          logger.addHandler( handler );
          handler.setLevel( Level.ALL );
          logger.setLevel( Level.ALL );
          julLogger = logger;
          julLogger.fine( "Configured jul-to-slf4j bridge for " + logger.getName() );
      }
  
      protected void setupLogLevel( String logLevel )
      {
          ILoggerFactory slf4jLoggerFactory = LoggerFactory.getILoggerFactory();
          Slf4jConfiguration slf4jConfiguration = Slf4jConfigurationFactory
                  .getConfiguration( slf4jLoggerFactory );
          if ( "debug".equals( logLevel ) )
          {
              slf4jConfiguration
                      .setRootLoggerLevel( Slf4jConfiguration.Level.DEBUG );
         }
         else if ( "info".equals( logLevel ) )
         {
             slf4jConfiguration
                     .setRootLoggerLevel( Slf4jConfiguration.Level.INFO );
         }
         else
         {
             slf4jConfiguration
                     .setRootLoggerLevel( Slf4jConfiguration.Level.ERROR );
         }
         slf4jConfiguration.activate();
     }
 
     protected static String buildClasspath()
     {
         StringBuilder classpath = new StringBuilder();
 
         // plugin classpath needs to come first
         ClassLoader pluginClassloader = Executor.class.getClassLoader();
         buildClasspath( classpath, pluginClassloader );
 
         ClassLoader coreClassloader = ConsoleLogger.class.getClassLoader();
         buildClasspath( classpath, coreClassloader );
 
         return classpath.toString();
     }
 
     static void buildClasspath( StringBuilder classpath, ClassLoader cl )
     {
         if ( cl instanceof URLClassLoader )
         {
             for ( URL url : ( (URLClassLoader) cl ).getURLs() )
             {
                 if ( "file".equalsIgnoreCase( url.getProtocol() ) )
                 {
                     try
                     {
                         String filename = URLDecoder.decode( url.getPath(), StandardCharsets.UTF_8.name() );
                         classpath.append( new File( filename ).getPath() ).append( File.pathSeparatorChar );
                     }
                     catch ( UnsupportedEncodingException e )
                     {
                         LOG.warn( "Ignoring " + url + " in classpath due to UnsupportedEncodingException", e );
                     }
                 }
             }
         }
     }
 
     protected static class ProcessStreamHandler implements Runnable
     {
         private static final int BUFFER_SIZE = 8192;
 
         private final BufferedInputStream in;
         private final BufferedOutputStream out;
 
         public static void start( InputStream in, OutputStream out )
         {
             Thread t = new Thread( new ProcessStreamHandler( in, out ) );
             t.start();
         }
 
         private ProcessStreamHandler( InputStream in, OutputStream out )
         {
             this.in = new BufferedInputStream( in );
             this.out = new BufferedOutputStream( out );
         }
 
         @Override
         public void run()
         {
             byte[] buffer = new byte[BUFFER_SIZE];
             try
             {
                 int count = in.read( buffer );
                 while ( count != -1 )
                 {
                     out.write( buffer, 0, count );
                     out.flush();
                     count = in.read( buffer );
                 }
                 out.flush();
             }
             catch ( IOException e )
             {
                 LOG.error( e.getMessage(), e );
             }
         }
     }
 }