//==============================================================================
// tribble/io/StreamCopier.java
//------------------------------------------------------------------------------

package tribble.io;


// System imports

import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.Reader;
import java.io.Writer;

import java.lang.Exception;
import java.lang.String;


// Local imports

// (None)


/*******************************************************************************
* Simple stream copying methods.
*
* @version	$Revision: 1.1 $ $Date: 2001/01/06 17:37:36 $
* @since	2001-01-06
* @author
*	David R. Tribble,
*	<a href="mailto:david@tribble.com">david@tribble.com</a>
*	<br>
*	<a href="../Copyright.html">Copyright</a> ©2001 by David R. Tribble,
*	all rights reserved.
*	<br>
*	Permission is granted to freely use and distribute this source code
*	provided that the original copyright and authorship notices remain
*	intact.
*/

public class StreamCopier
{
// Identification

    /** Revision information. */
    static final String		REV =
        "@(#)tribble/io/StreamCopier.java $Revision: 1.1 $ $Date: 2001/01/06 17:37:36 $\n";

    /** Embedded copyright notice. */
    static final String		COPYRIGHT =
        "\nCopyright \u00A9 2001 by David R. Tribble, all rights reserved.\n";


// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
// Public static constants

    /** Default data copying buffer size (in bytes). */
    public static final int	DFL_BUFSZ =	32*1024;


// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
// Public static methods

    /***************************************************************************
    * Test driver.
    *
    * @param	args
    * The command line arguments.
    *
    * @since	1.1, 2001-01-06
    */

    public static void main(final String[] args)
    {
        run(args);
        System.exit(0);
    }


    /***************************************************************************
    * Equivalent to: <br>
    * <tt><a href="#copy(java.io.InputStream, java.io.OutputStream, int)"
    * >copy</a>(in, out, {@link #DFL_BUFSZ})</tt>.
    *
    * @see	#copy(InputStream, OutputStream, int)
    *
    * @since	1.1, 2001-01-06
    */

    public static long copy(InputStream in, OutputStream out)
        throws IOException
    {
        return (copy(in, out, DFL_BUFSZ));
    }


    /***************************************************************************
    * Copies the contents of an input stream to an output stream.
    *
    * @param	in
    * The input stream, which is assumed to already be open for reading.
    * This object is synchronized.
    *
    * @param	out
    * The output stream, which is assumed to already be open for writing.
    * This object is synchronized.
    *
    * @param	bufsz
    * The buffer size to use (in bytes).
    *
    * @return
    * The number of bytes copied.
    *
    * @throws	IOException
    * Thrown if a read or write error occurs.
    *
    * @see	#copy(InputStream, OutputStream)
    *
    * @since	1.1, 2001-01-06
    */

    public static long copy(InputStream in, OutputStream out, int bufsz)
        throws IOException
    {
        long	nBytes = 0;
        byte[]	buf;

        // Allocate a data byte buffer
        buf = new byte[bufsz];

        // Copy bytes from the input stream to the output stream
        synchronized (out)
        {
            synchronized (in)
            {
                // Copy blocks of bytes from the input to the output stream
                for (;;)
                {
                    int		len;

                    // Read a block of bytes from the input stream
                    len = in.read(buf);		// May throw IOException

                    // Check for end of file
                    if (len <= 0)
                        break;

                    // Write the block of bytes to the output stream
                    out.write(buf, 0, len);	// May throw IOException
                    nBytes += len;
                }
            }

            // Clean up
            out.flush();
        }

        // Return the total number of bytes copied
        return (nBytes);
    }


    /***************************************************************************
    * Equivalent to: <br>
    * <tt><a href="#copy(java.io.Reader, java.io.Writer, int)"
    * >copy</a>(in, out, {@link #DFL_BUFSZ})</tt>.
    *
    * @see	#copy(Reader, Writer, int)
    *
    * @since	1.1, 2001-01-06
    */

    public static long copy(Reader in, Writer out)
        throws IOException
    {
        return (copy(in, out, DFL_BUFSZ));
    }


    /***************************************************************************
    * Copies the contents of an input stream to an output stream.
    *
    * @param	in
    * The input stream, which is assumed to already be open for reading.
    * This object is synchronized.
    *
    * @param	out
    * The output stream, which is assumed to already be open for writing.
    * This object is synchronized.
    *
    * @param	bufsz
    * The buffer size to use (in bytes).
    *
    * @return
    * The number of characters copied.
    *
    * @throws	IOException
    * Thrown if a read or write error occurs.
    *
    * @since	1.1, 2001-01-06
    */

    public static long copy(Reader in, Writer out, int bufsz)
        throws IOException
    {
        long	nChars = 0;
        char[]	data;

        // Copy chars from the input stream to the output stream
///...
if (nChars < 1)
throw new Error("Method tribble.io.StreamCopier.copy(Reader,Writer) is incomplete");

        // Return the total number of chars copied
        return (nChars);
    }


// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
// Protected static methods

    /***************************************************************************
    * Runs this class as a program.
    * Copies the contents of the standard input to the standard output.
    *
    * @since	1.1, 2001-01-06
    */

    protected static void run(final String[] args)
    {
        boolean		opt_char = false;

        // Parse command line option args
        for (int i = 0;  i < args.length  &&  args[i].charAt(0) == '-';  i++)
        {
            if (args[i].equals("-c"))
                opt_char = true;
            else if (args[i].equals("-b"))
                opt_char = false;
            else
                usage();
        }

        // Copy the contents of the standard input to the standard output
        try
        {
            // Copy the contents of the standard input to the standard output
            if (opt_char)
            {
                // Copy the stream using characters
                copy(new InputStreamReader(System.in),
                    new OutputStreamWriter(System.out));
            }
            else
            {
                // Copy the stream using bytes
                copy(System.in, System.out);
            }

            // Done
            System.exit(0);
        }
        catch (Exception ex)
        {
            // Display the exception
            System.err.println(ex);
            System.exit(1);
        }
    }


    /***************************************************************************
    * Displays a program usage message, then punts.
    *
    * <p>
    * This does not return, but calls {@link System#exit}.
    *
    * @since	1.1, 2001-01-06
    */

    protected static void usage()
    {
        // Display usage message
        System.out.println("[" + REV.substring(0, REV.length()-1) + "]\n");

        System.out.println(
            "Copies the standard input stream to the standard output.\n");

        System.out.println(
            "usage: java tribble.io.StreamCopier [-option...]\n");

        System.out.println(
            "Options:\n"
            + "    -b      Use byte streams.\n"
            + "    -c      Use character streams.");

        // Punt
        System.exit(255);
    }


// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
// Private methods

    /***************************************************************************
    * Constructor.
    * This is private to prevent empty instantiations.
    *
    * @since	1.1, 2001-01-06
    */

    private StreamCopier()
    {
        // Do nothing
    }
}

// End StreamCopier.java