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 org.apache.maven.surefire.testset.TestSetFailedException;
  import org.junit.After;
  import org.junit.Before;
  import org.junit.Test;
  import org.junit.runner.RunWith;
  
  import java.io.ByteArrayOutputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.PrintStream;
  import java.nio.ByteBuffer;
  import java.util.Iterator;
  import java.util.NoSuchElementException;
  import java.util.concurrent.BlockingQueue;
  import java.util.concurrent.CountDownLatch;
  import java.util.concurrent.ExecutionException;
  import java.util.concurrent.FutureTask;
  import java.util.concurrent.LinkedBlockingQueue;
  import java.util.concurrent.TimeUnit;
  
  import static java.nio.charset.StandardCharsets.ISO_8859_1;
  
  import static org.junit.Assert.assertFalse;
  import static org.junit.Assert.assertTrue;
  import static org.junit.Assert.fail;
  import static org.hamcrest.MatcherAssert.assertThat;
  import static org.hamcrest.Matchers.is;
  import static org.fest.assertions.Assertions.assertThat;
  
  /**
   * Testing singleton {@code MasterProcessReader} in multiple class loaders.
   *
   * @author <a href="mailto:tibordigana@apache.org">Tibor Digana (tibor17)</a>
   * @since 2.19
   */
  @RunWith( NewClassLoaderRunner.class )
  public class CommandReaderTest
  {
      private final BlockingQueue<Byte> blockingStream = new LinkedBlockingQueue<>();
      private InputStream realInputStream;
      private CommandReader reader;
  
      static class A {
      }
  
      static class B {
      }
  
      static class C {
      }
  
      static class D {
      }
  
      @Before
      public void init()
      {
          Thread.interrupted();
          realInputStream = System.in;
          addTestToPipeline( getClass().getName() );
          System.setIn( new SystemInputStream() );
          reader = CommandReader.getReader();
      }
  
      @After
      public void deinit()
      {
          reader.stop();
          System.setIn( realInputStream );
      }
  
      @Test
      public void readJustOneClass()
      {
          Iterator<String> it = reader.getIterableClasses( nul() ).iterator();
          assertTrue( it.hasNext() );
          assertThat( it.next(), is( getClass().getName() ) );
          reader.stop();
         assertFalse( it.hasNext() );
         try
         {
             it.next();
             fail();
         }
         catch ( NoSuchElementException e )
         {
             // expected
         }
     }
 
     @Test
     public void manyClasses()
     {
         Iterator<String> it1 = reader.getIterableClasses( nul() ).iterator();
         assertThat( it1.next(), is( getClass().getName() ) );
         addTestToPipeline( A.class.getName() );
         assertThat( it1.next(), is( A.class.getName() ) );
         addTestToPipeline( B.class.getName() );
         assertThat( it1.next(), is( B.class.getName() ) );
         addTestToPipeline( C.class.getName() );
         assertThat( it1.next(), is( C.class.getName() ) );
         addEndOfPipeline();
         addTestToPipeline( D.class.getName() );
         assertFalse( it1.hasNext() );
     }
 
     @Test
     public void twoIterators() throws Exception
     {
         Iterator<String> it1 = reader.getIterableClasses( nul() ).iterator();
 
         assertThat( it1.next(), is( getClass().getName() ) );
         addTestToPipeline( A.class.getName() );
         assertThat( it1.next(), is( A.class.getName() ) );
         addTestToPipeline( B.class.getName() );
 
         TimeUnit.MILLISECONDS.sleep( 200 ); // give the test chance to fail
 
         Iterator<String> it2 = reader.iterated();
 
         assertThat( it1.next(), is( B.class.getName() ) );
         addTestToPipeline( C.class.getName() );
 
         assertThat( it2.hasNext(), is( true ) );
         assertThat( it2.next(), is( getClass().getName() ) );
         assertThat( it2.hasNext(), is( true ) );
         assertThat( it2.next(), is( A.class.getName() ) );
         assertThat( it2 ).isEmpty();
 
         assertThat( it1.next(), is( C.class.getName() ) );
         addEndOfPipeline();
         assertThat( it1 ).isEmpty();
     }
 
     @Test( expected = NoSuchElementException.class )
     public void stopBeforeReadInThread()
         throws Throwable
     {
         Runnable runnable = new Runnable()
         {
             @Override
             public void run()
             {
                 Iterator<String> it = reader.getIterableClasses( nul() ).iterator();
                 assertThat( it.next(), is( CommandReaderTest.class.getName() ) );
             }
         };
         FutureTask<Object> futureTask = new FutureTask<>( runnable, null );
         Thread t = new Thread( futureTask );
         reader.stop();
         t.start();
         try
         {
             futureTask.get();
         }
         catch ( ExecutionException e )
         {
             throw e.getCause();
         }
     }
 
     @Test
     public void readTwoClassesInThread()
         throws Throwable
     {
         final CountDownLatch counter = new CountDownLatch( 1 );
         Runnable runnable = new Runnable()
         {
             @Override
             public void run()
             {
                 Iterator<String> it = reader.getIterableClasses( nul() ).iterator();
                 assertThat( it.next(), is( CommandReaderTest.class.getName() ) );
                 counter.countDown();
                 assertThat( it.next(), is( PropertiesWrapperTest.class.getName() ) );
             }
         };
         FutureTask<Object> futureTask = new FutureTask<>( runnable, null );
         Thread t = new Thread( futureTask );
         t.start();
         counter.await();
         addTestToPipeline( PropertiesWrapperTest.class.getName() );
         try
         {
             futureTask.get();
         }
         catch ( ExecutionException e )
         {
             throw e.getCause();
         }
     }
 
     @Test( timeout = 15000 )
     public void shouldAwaitReaderUp()
         throws TestSetFailedException
     {
         assertTrue( reader.awaitStarted() );
         reader.stop();
         assertFalse( reader.awaitStarted() );
     }
 
     private class SystemInputStream
         extends InputStream
     {
         @Override
         public int read()
             throws IOException
         {
             try
             {
                 return CommandReaderTest.this.blockingStream.take();
             }
             catch ( InterruptedException e )
             {
                 throw new IOException( e );
             }
         }
     }
 
     private void addTestToPipeline( String cls )
     {
         byte[] clazz = cls.getBytes( ISO_8859_1 );
         ByteBuffer buffer = ByteBuffer.allocate( 8 + clazz.length )
             .putInt( MasterProcessCommand.RUN_CLASS.getId() )
             .putInt( clazz.length )
             .put( clazz );
         buffer.rewind();
         for ( ; buffer.hasRemaining(); )
         {
             blockingStream.add( buffer.get() );
         }
     }
 
     private void addEndOfPipeline()
     {
         ByteBuffer buffer = ByteBuffer.allocate( 8 )
                 .putInt( MasterProcessCommand.TEST_SET_FINISHED.getId() )
                 .putInt( 0 );
         buffer.rewind();
         for ( ; buffer.hasRemaining(); )
         {
             blockingStream.add( buffer.get() );
         }
     }
 
     private static PrintStream nul()
     {
         return new PrintStream( new ByteArrayOutputStream() );
     }
 }