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-rw-r--r--ChangeLog6
-rw-r--r--docs/tutorials/015/Client_i.cpp2
-rw-r--r--docs/tutorials/015/Compressor.cpp103
-rw-r--r--docs/tutorials/015/Compressor.h39
-rw-r--r--docs/tutorials/015/Handler.cpp6
-rw-r--r--docs/tutorials/015/Makefile.client4
-rw-r--r--docs/tutorials/015/Makefile.server5
-rw-r--r--docs/tutorials/015/Protocol_Stream.cpp135
-rw-r--r--docs/tutorials/015/Protocol_Stream.h35
-rw-r--r--docs/tutorials/015/Protocol_Task.cpp3
-rw-r--r--docs/tutorials/015/Xmit.cpp7
-rw-r--r--docs/tutorials/015/client.cpp49
-rw-r--r--docs/tutorials/015/page01.html3
13 files changed, 245 insertions, 152 deletions
diff --git a/ChangeLog b/ChangeLog
index 046af287b80..cc14b8e7c23 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Tue Aug 19 10:07:47 2003 Douglas C. Schmidt <schmidt@ace.cs.wustl.edu>
+
+ * doc/tutorials/015: Added support for compression. Thanks
+ to Andrew Marlow <apm35@student.open.ac.uk> for contributing
+ this.
+
Mon Aug 18 21:26:51 UTC 2003 Don Hinton <dhinton@dresystems.com>
* bin/MakeProjectCreator/modules/GNUACEWorkspaceCreator.pm:
diff --git a/docs/tutorials/015/Client_i.cpp b/docs/tutorials/015/Client_i.cpp
index 6415fed1966..5039fde992e 100644
--- a/docs/tutorials/015/Client_i.cpp
+++ b/docs/tutorials/015/Client_i.cpp
@@ -39,7 +39,7 @@ int Client::open( void )
// to ensure that our data is in the correct format when
// received by the server. Thus, we open the stream and
// transfer ownership of the peer.
- return stream().open( peer() );
+ return stream().open( peer(), 0, true);
}
// The remainder of the functions just delegate to the stream.
diff --git a/docs/tutorials/015/Compressor.cpp b/docs/tutorials/015/Compressor.cpp
index bbe76eb1a69..1cb1bf8bbf9 100644
--- a/docs/tutorials/015/Compressor.cpp
+++ b/docs/tutorials/015/Compressor.cpp
@@ -1,101 +1,60 @@
-
// $Id$
+#include "ZlibCompressor.h"
#include "Compressor.h"
#include "ace/SOCK_Stream.h"
-Compressor::Compressor( void )
- : Protocol_Task()
+#include <zlib.h>
+
+Compressor::Compressor(AlgorithmCode algorithm)
{
- ;
+ switch(algorithm)
+ {
+ case COMPRESSION_ZLIB:
+ compressor_ = new ZlibCompressor();
+ break;
+
+ default:
+ compressor_ = 0;
+ break;
+ }
}
Compressor::~Compressor(void)
{
- ;
+ delete compressor_;
}
-/* This is where you insert your compression code. Most compressors
- want to work on a block of data instead of a byte-stream.
- Fortunately the message block has a block that can be compressed.
- Take a look at libz for a quick way to add compression to your
- apps
- */
-int Compressor::send(ACE_Message_Block *message, ACE_Time_Value *timeout)
+int Compressor::send (ACE_Message_Block *message, ACE_Time_Value *timeout)
{
- ACE_UNUSED_ARG(message);
- ACE_UNUSED_ARG(timeout);
-
- ACE_DEBUG ((LM_INFO, "(%P|%t) Compressor::send() compressing (%s)\n", message->rd_ptr() ));
-
- // Create a block to hold the compressed data. I belive libz
- // recommends a buffer about 10-20% larger than the source.
- // Other libraries/algorithms may have their own quirks.
- ACE_Message_Block * compressed = new ACE_Message_Block(
- message->size() +16 );
+ if (compressor_ == 0)
+ return -1;
- // Perform a bogus compression algorithm. 'CD' just tells me
- // that this is compressed data and when we "decompress" we'll
- // look for this signature to validate the data received.
- ACE_OS::sprintf( compressed->wr_ptr(), "CD:%s", message->rd_ptr() );
- compressed->wr_ptr( strlen(compressed->wr_ptr())+1 );
+ ACE_Message_Block* compressed = 0;
+ int retval = compressor_->send(message, timeout, compressed);
- // Send the compressed data down the stream to the next module
+ // Send the compressed data down the stream to the next module
this->put_next( compressed );
- // We're done here.
+ // We're done here.
message->release();
- return( 0 );
+ return retval;
}
-/* And here's the decompression side. We've written Xmit/Recv so that
- we're guaranteed to get an entire block of compressed data. If
- we'd used recv() in the Recv object then we might have gotten a
- partial block and that may not decompress very nicely.
- */
-int Compressor::recv(ACE_Message_Block *message, ACE_Time_Value *timeout)
+int Compressor::recv (ACE_Message_Block *message, ACE_Time_Value *timeout)
{
- ACE_UNUSED_ARG(message);
- ACE_UNUSED_ARG(timeout);
+ if (compressor_ == 0)
+ return -1;
- ACE_DEBUG ((LM_INFO, "(%P|%t) Compress::recv() decompressing (%s)\n", message->rd_ptr() ));
+ ACE_Message_Block* decompressed = 0;
+ int retval = compressor_->recv(message, timeout, decompressed);
- // Room for the decompressed data. In the real world you
- // would probably want to send the original (uncompressed)
- // data size in the message. You can predict the maximum
- // possible decompression size but it's cheap and easy just to
- // send that along. Look again at how I do exacly that
- // between Xmit and Recv.
- ACE_Message_Block * decompressed = new ACE_Message_Block(
- message->size() + 16 );
-
- // Check for our signature. Even when you use a real
- // compression algorithm you may want to include your own
- // signature so that you can verify the block. It pays to be
- // paranoid!
- if( ACE_OS::strncmp( message->rd_ptr(), "CD:", 3 ) )
- {
- ACE_DEBUG ((LM_INFO, "(%P|%t) Improperly encompressed data.\n" ));
- message->release();
- return(-1);
- }
-
- // Skip past the signature before going any further.
- message->rd_ptr( 3 );
-
- // Perform a bogus decompression algorithm. This is where you
- // would feed to libz or your favorite decompressor. (It's
- // costly but you could invoke popen() on gzip!)
- ACE_OS::sprintf( decompressed->wr_ptr(), "%s", message->rd_ptr() );
- decompressed->wr_ptr( strlen(decompressed->wr_ptr())+1 );
-
- // Recv the decompressed data down the stream to the next module
+ // Recv the decompressed data down the stream to the next module
this->put_next( decompressed );
- // We're done here.
+ // We're done here.
message->release();
- return( 0 );
+ return retval;
}
-
diff --git a/docs/tutorials/015/Compressor.h b/docs/tutorials/015/Compressor.h
index cb4c7248cce..cf86f0caedc 100644
--- a/docs/tutorials/015/Compressor.h
+++ b/docs/tutorials/015/Compressor.h
@@ -1,35 +1,40 @@
// $Id$
#ifndef COMPRESSOR_H
-#define COMPRESSOR_h
+#define COMPRESSOR_H
#include "Protocol_Task.h"
-/* A reallly dumb compression object. (It actually adds 3 bytes to
- every message block.)
-*/
+#include "CompressorBase.h"
+
class Compressor : public Protocol_Task
{
public:
+ enum AlgorithmCode
+ {
+ COMPRESSION_NONE = 0
+ , COMPRESSION_ZLIB = 1
+ , COMPRESSION_RLE = 2 // for future expansion
+ , COMPRESSION_BZIP2 = 3 // for future expansion
+ };
- typedef Protocol_Task inherited;
-
- Compressor (void);
+ Compressor(AlgorithmCode algorithm);
- ~Compressor (void);
+ virtual ~Compressor (void);
protected:
- // This is called when the compressor is on the downstream side.
- // We'll take the message, compress it and move it along to the next
- // module.
- int send (ACE_Message_Block *message,
- ACE_Time_Value *timeout);
+ // This is called when the compressor is on the
+ // downstream side. We'll take the message, compress it
+ // and move it along to the next module.
+ virtual int send (ACE_Message_Block *message, ACE_Time_Value *timeout);
+
+ // This one is called on the upstream side. No surprise: we
+ // decompress the data and send it on up the stream.
+ virtual int recv (ACE_Message_Block *message, ACE_Time_Value *timeout);
- // This one is called on the upstream side. No surprise: we
- // decompress the data and send it on up the stream.
- int recv (ACE_Message_Block *message,
- ACE_Time_Value *timeout);
+private:
+ CompressorBase* compressor_;
};
#endif /* COMPRESSOR_H */
diff --git a/docs/tutorials/015/Handler.cpp b/docs/tutorials/015/Handler.cpp
index e940a8a8ce7..201d3605c41 100644
--- a/docs/tutorials/015/Handler.cpp
+++ b/docs/tutorials/015/Handler.cpp
@@ -9,7 +9,7 @@
more when we talk about the stream in detail. For now it's enough
to know that Handler_Task::recv() will be invoked by the stream
after data from the client has been received and processed (eg --
- decrypted, uncompressed, and whatever else the protocol requires.)
+ uncompressed and whatever else the protocol requires.)
*/
class Handler_Task : public Protocol_Task
{
@@ -66,7 +66,7 @@ int Handler::open (void *)
// read client requests and send our responses. We also
// provide a Handler_Task instance that will ultimately be
// responsible for processing any client data we receive.
- int rval = stream().open( this->peer(), new Handler_Task() );
+ int rval = stream().open( this->peer(), new Handler_Task(), false );
// Of course, we have to account for the chance that the
// stream's open() may fail.
@@ -161,7 +161,7 @@ int Handler_Task::recv(ACE_Message_Block * message,
ACE_DEBUG ((LM_INFO, "(%P|%t) Handler_Task::recv() got (%s)\n", message->rd_ptr() ));
// Create a response message to send to the client
- ACE_Message_Block * response = new ACE_Message_Block( 128 );
+ ACE_Message_Block * response = new ACE_Message_Block( 1024 );
// Nothing very original about this I'm afraid...
ACE_OS::sprintf( response->wr_ptr(), "You Said: (%s)", message->rd_ptr() );
diff --git a/docs/tutorials/015/Makefile.client b/docs/tutorials/015/Makefile.client
index 20680aea15b..440b813cfb3 100644
--- a/docs/tutorials/015/Makefile.client
+++ b/docs/tutorials/015/Makefile.client
@@ -11,8 +11,10 @@ FILES += Protocol_Stream
FILES += Protocol_Task
FILES += Xmit
FILES += Recv
+FILES += CompressionSocket
FILES += Compressor
-FILES += Crypt
+FILES += CompressorBase
+FILES += ZlibCompressor
FILES += Client_i
BUILD = $(VBIN)
diff --git a/docs/tutorials/015/Makefile.server b/docs/tutorials/015/Makefile.server
index 109cecc8e90..bc44c1d3867 100644
--- a/docs/tutorials/015/Makefile.server
+++ b/docs/tutorials/015/Makefile.server
@@ -11,9 +11,10 @@ FILES += Protocol_Stream
FILES += Protocol_Task
FILES += Xmit
FILES += Recv
+FILES += CompressionSocket
FILES += Compressor
-FILES += Crypt
-
+FILES += CompressorBase
+FILES += ZlibCompressor
FILES += Handler
FILES += Server_i
diff --git a/docs/tutorials/015/Protocol_Stream.cpp b/docs/tutorials/015/Protocol_Stream.cpp
index e1c210ec119..6b7fd05c3cc 100644
--- a/docs/tutorials/015/Protocol_Stream.cpp
+++ b/docs/tutorials/015/Protocol_Stream.cpp
@@ -7,15 +7,12 @@
#include "Recv.h"
#include "Compressor.h"
-#include "Crypt.h"
#include "ace/Stream_Modules.h"
/* You can choose at compile time to include/exclude the protocol
pieces.
*/
-#define ENABLE_COMPRESSION
-#define ENABLE_ENCRYPTION
// The usual typedefs to make things easier to type.
typedef ACE_Module<ACE_MT_SYNCH> Module;
@@ -49,7 +46,8 @@ Protocol_Stream::~Protocol_Stream (void)
*/
int
Protocol_Stream::open (ACE_SOCK_Stream &peer,
- Protocol_Task *reader)
+ Protocol_Task *reader,
+ bool isOriginator)
{
// Initialize our peer() to read/write the socket we're given
peer_.set_handle (peer.get_handle ());
@@ -73,7 +71,7 @@ Protocol_Stream::open (ACE_SOCK_Stream &peer,
// Add any other protocol tasks to the stream. Each one is added at
// the head. The net result is that Xmit/Recv are at the tail.
- if (this->open () == -1)
+ if (this->open (isOriginator) == -1)
return -1;
// If a reader task was provided then push that in as the upstream
@@ -96,32 +94,115 @@ Protocol_Stream::open (ACE_SOCK_Stream &peer,
return 0;
}
-/* Add the necessary protocol objects to the stream. The way we're
- pushing things on we will compress the data before encrypting it.
+/* Add the necessary protocol objects to the stream.
*/
+
int
-Protocol_Stream::open (void)
+Protocol_Stream::open (bool isOriginator)
{
-#if defined (ENABLE_ENCRYPTION)
- if (stream ().push (new Module ("crypt",
- new Crypt (),
- new Crypt ())) == -1)
- ACE_ERROR_RETURN ((LM_ERROR,
- "%p\n",
- "stream().push(crypt)"),
- -1);
-#endif /* ENABLE_ENCRYPTION */
+ // We are protocol version 1, we only support ZLIB compression currently.
-#if defined (ENABLE_COMPRESSION)
- if (stream ().push (new Module ("compress",
- new Compressor (),
- new Compressor ())) == -1)
- ACE_ERROR_RETURN ((LM_ERROR,
- "%p\n",
- "stream().push(comprssor)"),
- -1);
-#endif /* ENABLE_COMPRESSION */
- return 0;
+ ProtocolVersion pversion = PROTOCOL_VERSION_1;
+ Compressor::AlgorithmCode acode = Compressor::COMPRESSION_ZLIB;
+
+ // If we are the originator, we put a message asking for
+ // what compression is to be used.
+
+ if (isOriginator)
+ {
+ ACE_Message_Block * message = new ACE_Message_Block( 1024 );
+
+ CompressionNegotiation neg;
+ neg.protocolVersion = pversion;
+ neg.algorithmCount = 1;
+ neg.algorithm[0] = acode;
+
+ memcpy(message->wr_ptr(), &neg, sizeof(neg));
+ message->wr_ptr(sizeof(neg));
+
+ if (put(message, 0) < 0)
+ {
+ return -1;
+ }
+
+ ACE_Message_Block * response;
+ if (get(response, 0) < 0)
+ {
+ return -1;
+ }
+
+ CompressionNegotiationReply negResponse;
+ memcpy(&negResponse, response->rd_ptr(), sizeof(negResponse));
+
+ response->release();
+ if (negResponse.errorCode != NEGOTIATE_OK)
+ {
+ return -1;
+ }
+ }
+ else
+ {
+ // Read the message to see what algorithm the originator speaks.
+
+ ACE_Message_Block* message;
+ if (get(message, 0) < 0)
+ {
+ return -1;
+ }
+
+ CompressionNegotiation neg;
+ memcpy(&neg, message->rd_ptr(), sizeof(neg));
+ message->release();
+
+ // Reply to handshake message.
+
+ CompressionNegotiationReply negResponse;
+ negResponse.errorCode = NEGOTIATE_OK;
+ negResponse.protocolVersion = PROTOCOL_VERSION_1;
+
+ if (neg.protocolVersion == PROTOCOL_VERSION_1)
+ {
+ // Ensure that incoming algorithms include the one we support.
+
+ negResponse.algorithm = Compressor::COMPRESSION_NONE;
+ for (int i = 0; i < neg.algorithmCount; i++)
+ {
+ if (neg.algorithm[i] == acode)
+ {
+ negResponse.algorithm = acode;
+ break;
+ }
+ }
+ if (negResponse.algorithm == Compressor::COMPRESSION_NONE)
+ {
+ negResponse.errorCode = NEGOTIATE_UNSUPPORTED_ALGORITHM;
+ }
+ }
+ else
+ {
+ negResponse.errorCode = NEGOTIATE_UNSUPPORTED_VERSION;
+ }
+
+ ACE_Message_Block* reply = new ACE_Message_Block( 1024 );
+ memcpy(reply->wr_ptr(), &negResponse, sizeof(negResponse));
+ reply->wr_ptr(sizeof(neg));
+
+ if (put(reply, 0) < 0)
+ {
+ return -1;
+ }
+ }
+
+ // Add the compression component to the pipeline.
+
+ if (stream ().push (new Module ("compress",
+ new Compressor (acode),
+ new Compressor (acode))) == -1)
+ ACE_ERROR_RETURN ((LM_ERROR,
+ "%p\n",
+ "stream().push(compressor)"),
+ -1);
+ return 0;
}
// Closing the Protocol_Stream is as simple as closing the ACE_Stream.
diff --git a/docs/tutorials/015/Protocol_Stream.h b/docs/tutorials/015/Protocol_Stream.h
index 5209ed68907..f846f9efb54 100644
--- a/docs/tutorials/015/Protocol_Stream.h
+++ b/docs/tutorials/015/Protocol_Stream.h
@@ -33,7 +33,8 @@ public:
// reader task just below the stream head so that it can process
// data read from the peer.
int open (ACE_SOCK_Stream &peer,
- Protocol_Task *reader = 0);
+ Protocol_Task *reader,
+ bool isOriginator);
// Close the stream. All of the tasks & modules will also be
// closed.
@@ -64,6 +65,32 @@ public:
}
private:
+ enum ProtocolVersion
+ {
+ PROTOCOL_VERSION_1 = 1
+ };
+
+ enum CompressionNegotiationErrorCode
+ {
+ NEGOTIATE_OK = 0
+ , NEGOTIATE_UNSUPPORTED_VERSION = -1
+ , NEGOTIATE_UNSUPPORTED_ALGORITHM = -2
+ };
+
+ struct CompressionNegotiation
+ {
+ unsigned char protocolVersion;
+ unsigned char algorithmCount;
+ unsigned char algorithm[5]; // as of protocol version 1.
+ };
+
+ struct CompressionNegotiationReply
+ {
+ signed char errorCode;
+ unsigned char protocolVersion;
+ unsigned char algorithm;
+ };
+
// Our peer connection
ACE_SOCK_Stream peer_;
@@ -71,16 +98,18 @@ private:
Stream stream_;
// A task which is capable of receiving data on a socket.
- // Note that this is only useful by server-side applications.
+ // Note that this is only useful by client-side applications.
Recv *recv_;
+ bool isHandshakeComplete_;
+
Stream &stream (void)
{
return this->stream_;
}
// Install the protocol tasks into the stream.
- int open (void);
+ int open (bool isOriginator);
};
#endif /* PROTOCOL_STREAM_H */
diff --git a/docs/tutorials/015/Protocol_Task.cpp b/docs/tutorials/015/Protocol_Task.cpp
index 6060fb1ddfa..da202a50b46 100644
--- a/docs/tutorials/015/Protocol_Task.cpp
+++ b/docs/tutorials/015/Protocol_Task.cpp
@@ -46,7 +46,8 @@ int Protocol_Task::svc(void)
we're moving data upstream or downstream and invoke the appropriate
virtual function to handle it.
*/
-int Protocol_Task::process(ACE_Message_Block * message, ACE_Time_Value *timeout)
+int Protocol_Task::process(ACE_Message_Block * message,
+ ACE_Time_Value *timeout)
{
if( this->is_writer() )
{
diff --git a/docs/tutorials/015/Xmit.cpp b/docs/tutorials/015/Xmit.cpp
index 28be01b1d25..4f2ed4f274f 100644
--- a/docs/tutorials/015/Xmit.cpp
+++ b/docs/tutorials/015/Xmit.cpp
@@ -47,10 +47,10 @@ int Xmit::send(ACE_Message_Block *message, ACE_Time_Value *timeout)
{
int rval;
- ACE_DEBUG ((LM_INFO, "(%P|%t) Xmit::send() sending (%s)(%d)\n", message->rd_ptr(), message->length() ));
+ ACE_DEBUG ((LM_INFO, "(%P|%t) Xmit::send() sending buff of len %d\n", message->length() ));
/* Since we're going to be sending data that may have been
- compressed and encrypted it's probably important for the
+ compressed it's probably important for the
receiver to get an entire "block" instead of having a
partial read.
@@ -75,7 +75,8 @@ int Xmit::send(ACE_Message_Block *message, ACE_Time_Value *timeout)
containing msize and the message data and send it all at
once.
*/
- rval = this->peer().send_n( message->rd_ptr(), message->length(), 0, timeout );
+ rval = this->peer().send_n(message->rd_ptr(),
+ message->length(), 0, timeout);
// Release the message block since we're done with it.
message->release();
diff --git a/docs/tutorials/015/client.cpp b/docs/tutorials/015/client.cpp
index 93041dcdfdd..af4433d4a23 100644
--- a/docs/tutorials/015/client.cpp
+++ b/docs/tutorials/015/client.cpp
@@ -8,42 +8,51 @@
int main(int argc, char *argv[])
{
- // How many messages will we send?
+ // How many messages will we send?
int mcount = argc > 1 ? ACE_OS::atoi(argv[1]) : 3;
- // Construct a Client with our desired endpoint.
+ // Construct a Client with our desired endpoint.
Client client(ACE_DEFAULT_SERVER_PORT,ACE_DEFAULT_SERVER_HOST);
- // Attempt to open the connection to the server.
+ // Attempt to open the connection to the server.
if( client.open() == -1 )
{
ACE_ERROR_RETURN ((LM_ERROR, "%p\n", "Client::open()"), -1);
}
- // Send a few messages to the server and get some responses...
+ // Send a few messages to the server and get some responses...
for( int i = 0 ; i < mcount ; ++i )
{
- // Since we'll be using a Protocol Stream (even though we
- // don't know that at this level) we require the use of
- // ACE_Message_Block objects to send/receive data.
- ACE_Message_Block * message = new ACE_Message_Block( 128 );
-
- // Construct a silly message to send to the server.
- // Notice that we're careful to add one to the strlen() so
- // that we also send the end-of-string NULL character.
- ACE_OS::sprintf (message->wr_ptr (), "This is message %d.", i);
+ // Since we'll be using a Protocol Stream (even though we
+ // don't know that at this level) we require the use of
+ // ACE_Message_Block objects to send/receive data.
+ ACE_Message_Block * message = new ACE_Message_Block( 1024 );
+
+ // Construct a silly message to send to the server.
+ // Notice that we're careful to add one to the strlen() so
+ // that we also send the end-of-string NULL character.
+ ACE_OS::sprintf (message->wr_ptr (),
+ "This is message %d. It is a bit verbose because "
+ "we want there to be an opportunity for some compression to occur. "
+ "That's why it has a whofflly style and goes on and on and on.",
+ i);
message->wr_ptr (strlen (message->rd_ptr ())+1);
- // client will take ownership of the message block so that
- // we don't have to remember to release(). We *do* have
- // to remember not to use it after put() since it may be
- // released almost immediately.
- client.put( message );
+ // client will take ownership of the message block so that
+ // we don't have to remember to release(). We *do* have
+ // to remember not to use it after put() since it may be
+ // released almost immediately.
+ if (client.put( message ) < 0)
+ {
+ fprintf(stderr, "%s:%d: client put failed.\n", __FILE__, __LINE__);
+ return -1;
+ }
ACE_Message_Block * response;
- // get() takes an ACE_Message_Block pointer reference. We then
- // assume ownership of it and must release() when we're done.
+ // get() takes an ACE_Message_Block pointer reference. We then
+ // assume ownership of it and must release() when we're done.
+
if( client.get( response ) == -1 )
{
ACE_DEBUG ((LM_INFO, "(%P|%t) Failed to get response from server\n" ));
diff --git a/docs/tutorials/015/page01.html b/docs/tutorials/015/page01.html
index 0709a089c19..7d66f966e77 100644
--- a/docs/tutorials/015/page01.html
+++ b/docs/tutorials/015/page01.html
@@ -98,8 +98,7 @@ now from the previous tutorials.
etc.)
</UL>
<P>
-<font size=-1>* Ok, I didn't really implement encryption and
- compression objects. I'll leave that as a thought
+<font size=-1>* Ok, I didn't really implement encryption objects. I'll leave that as a thought
exercise!</font>
<P><HR WIDTH="100%">
<CENTER>[<A HREF="../online-tutorials.html">Tutorial Index</A>] [<A HREF="page02.html">Continue This Tutorial</A>]</CENTER>