Commons IO example source code file (DemuxTestCase.java)

This example Commons IO source code file (DemuxTestCase.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Commons IO tags/keywords

data1, data2, data3, data3, data4, data4, demuxinputstream, demuxoutputstream, exception, exception, io, string, string, t3, thread, util

The Commons IO DemuxTestCase.java source code

/*
 * 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.
 */
package org.apache.commons.io;

import java.io.ByteArrayInputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Random;

import junit.framework.TestCase;

import org.apache.commons.io.input.DemuxInputStream;
import org.apache.commons.io.output.ByteArrayOutputStream;
import org.apache.commons.io.output.DemuxOutputStream;

/**
 * Basic unit tests for the multiplexing streams.
 *
 * @author <a href="mailto:peter@apache.org">Peter Donald
 */
public class DemuxTestCase
    extends TestCase
{
    private static final String T1 = "Thread1";
    private static final String T2 = "Thread2";
    private static final String T3 = "Thread3";
    private static final String T4 = "Thread4";

    private static final String DATA1 = "Data for thread1";
    private static final String DATA2 = "Data for thread2";
    private static final String DATA3 = "Data for thread3";
    private static final String DATA4 = "Data for thread4";

    private static final Random c_random = new Random();
    private HashMap<String, ByteArrayOutputStream> m_outputMap = new HashMap();
    private HashMap<String, Thread> m_threadMap = new HashMap();

    public DemuxTestCase( String name )
    {
        super( name );
    }

    private String getOutput( String threadName )
    {
        ByteArrayOutputStream output =
            m_outputMap.get( threadName );
        assertNotNull( "getOutput()", output );

        return output.toString();
    }

    private String getInput( String threadName )
    {
        ReaderThread thread = (ReaderThread)m_threadMap.get( threadName );
        assertNotNull( "getInput()", thread );

        return thread.getData();
    }

    private void doStart()
        throws Exception
    {
        Iterator<String> iterator = m_threadMap.keySet().iterator();
        while( iterator.hasNext() )
        {
            String name = iterator.next();
            Thread thread = m_threadMap.get( name );
            thread.start();
        }
    }

    private void doJoin()
        throws Exception
    {
        Iterator<String> iterator = m_threadMap.keySet().iterator();
        while( iterator.hasNext() )
        {
            String name = iterator.next();
            Thread thread = m_threadMap.get( name );
            thread.join();
        }
    }

    private void startWriter( String name,
                              String data,
                              DemuxOutputStream demux )
        throws Exception
    {
        ByteArrayOutputStream output = new ByteArrayOutputStream();
        m_outputMap.put( name, output );
        WriterThread thread =
            new WriterThread( name, data, output, demux );
        m_threadMap.put( name, thread );
    }

    private void startReader( String name,
                              String data,
                              DemuxInputStream demux )
        throws Exception
    {
        ByteArrayInputStream input = new ByteArrayInputStream( data.getBytes() );
        ReaderThread thread = new ReaderThread( name, input, demux );
        m_threadMap.put( name, thread );
    }

    public void testOutputStream()
        throws Exception
    {
        DemuxOutputStream output = new DemuxOutputStream();
        startWriter( T1, DATA1, output );
        startWriter( T2, DATA2, output );
        startWriter( T3, DATA3, output );
        startWriter( T4, DATA4, output );

        doStart();
        doJoin();

        assertEquals( "Data1", DATA1, getOutput( T1 ) );
        assertEquals( "Data2", DATA2, getOutput( T2 ) );
        assertEquals( "Data3", DATA3, getOutput( T3 ) );
        assertEquals( "Data4", DATA4, getOutput( T4 ) );
    }

    public void testInputStream()
        throws Exception
    {
        DemuxInputStream input = new DemuxInputStream();
        startReader( T1, DATA1, input );
        startReader( T2, DATA2, input );
        startReader( T3, DATA3, input );
        startReader( T4, DATA4, input );

        doStart();
        doJoin();

        assertEquals( "Data1", DATA1, getInput( T1 ) );
        assertEquals( "Data2", DATA2, getInput( T2 ) );
        assertEquals( "Data3", DATA3, getInput( T3 ) );
        assertEquals( "Data4", DATA4, getInput( T4 ) );
    }

    private static class ReaderThread
        extends Thread
    {
        private StringBuffer m_buffer = new StringBuffer();
        private InputStream m_input;
        private DemuxInputStream m_demux;

        ReaderThread( String name,
                      InputStream input,
                      DemuxInputStream demux )
        {
            super( name );
            m_input = input;
            m_demux = demux;
        }

        public String getData()
        {
            return m_buffer.toString();
        }

        @Override
        public void run()
        {
            m_demux.bindStream( m_input );

            try
            {
                int ch = m_demux.read();
                while( -1 != ch )
                {
                    //System.out.println( "Reading: " + (char)ch );
                    m_buffer.append( (char)ch );

                    int sleepTime = Math.abs( c_random.nextInt() % 10 );
                    Thread.sleep( sleepTime );
                    ch = m_demux.read();
                }
            }
            catch( Exception e )
            {
                e.printStackTrace();
            }
        }
    }

    private static class WriterThread
        extends Thread
    {
        private byte[] m_data;
        private OutputStream m_output;
        private DemuxOutputStream m_demux;

        WriterThread( String name,
                      String data,
                      OutputStream output,
                      DemuxOutputStream demux )
        {
            super( name );
            m_output = output;
            m_demux = demux;
            m_data = data.getBytes();
        }

        @Override
        public void run()
        {
            m_demux.bindStream( m_output );
            for( int i = 0; i < m_data.length; i++ )
            {
                try
                {
                    //System.out.println( "Writing: " + (char)m_data[ i ] );
                    m_demux.write( m_data[ i ] );
                    int sleepTime = Math.abs( c_random.nextInt() % 10 );
                    Thread.sleep( sleepTime );
                }
                catch( Exception e )
                {
                    e.printStackTrace();
                }
            }
        }
    }
}