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Posted to fop-commits@xmlgraphics.apache.org by fo...@locus.apache.org on 2000/06/26 23:37:43 UTC
cvs commit: xml-fop/src/org/apache/fop/messaging DefaultMessageListener.java MessageEvent.java MessageHandler.java MessageListener.java
fotis 00/06/26 14:37:42
Added: src/org/apache/fop/messaging DefaultMessageListener.java
MessageEvent.java MessageHandler.java
MessageListener.java
Log:
a simple message handler, which allows logging Fop messages to a file or implementation of a MessageListener
Revision Changes Path
1.1 xml-fop/src/org/apache/fop/messaging/DefaultMessageListener.java
Index: DefaultMessageListener.java
===================================================================
/*
============================================================================
The Apache Software License, Version 1.1
============================================================================
Copyright (C) 1999 The Apache Software Foundation. All rights reserved.
Redistribution and use in source and binary forms, with or without modifica-
tion, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
3. The end-user documentation included with the redistribution, if any, must
include the following acknowledgment: "This product includes software
developed by the Apache Software Foundation (http://www.apache.org/)."
Alternately, this acknowledgment may appear in the software itself, if
and wherever such third-party acknowledgments normally appear.
4. The names "Fop" and "Apache Software Foundation" must not be used to
endorse or promote products derived from this software without prior
written permission. For written permission, please contact
apache@apache.org.
5. Products derived from this software may not be called "Apache", nor may
"Apache" appear in their name, without prior written permission of the
Apache Software Foundation.
THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
APACHE SOFTWARE FOUNDATION OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLU-
DING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
This software consists of voluntary contributions made by many individuals
on behalf of the Apache Software Foundation and was originally created by
James Tauber <jt...@jtauber.com>. For more information on the Apache
Software Foundation, please see <http://www.apache.org/>.
*/
package org.apache.fop.messaging;
/**
* A trivial implementation of a MessageListener
* For further explanation
* @see MessageListener
*/
public class DefaultMessageListener implements MessageListener{
/**
* The method processMessage has to be overwritten to handle the MessageEvents.
* The message type (information or error) is accessible via event.getMessageType().
*/
public void processMessage (MessageEvent event) {
switch (event.getMessageType()) {
case MessageEvent.ERROR:
System.err.print("ERROR: "+event.getMessage());
break;
case MessageEvent.LOG:
System.out.print("LOG: "+event.getMessage());
break;
default:
System.out.print("Unknown message type: "+event.getMessage());
}
}
}
1.1 xml-fop/src/org/apache/fop/messaging/MessageEvent.java
Index: MessageEvent.java
===================================================================
/*
============================================================================
The Apache Software License, Version 1.1
============================================================================
Copyright (C) 1999 The Apache Software Foundation. All rights reserved.
Redistribution and use in source and binary forms, with or without modifica-
tion, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
3. The end-user documentation included with the redistribution, if any, must
include the following acknowledgment: "This product includes software
developed by the Apache Software Foundation (http://www.apache.org/)."
Alternately, this acknowledgment may appear in the software itself, if
and wherever such third-party acknowledgments normally appear.
4. The names "Fop" and "Apache Software Foundation" must not be used to
endorse or promote products derived from this software without prior
written permission. For written permission, please contact
apache@apache.org.
5. Products derived from this software may not be called "Apache", nor may
"Apache" appear in their name, without prior written permission of the
Apache Software Foundation.
THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
APACHE SOFTWARE FOUNDATION OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLU-
DING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
This software consists of voluntary contributions made by many individuals
on behalf of the Apache Software Foundation and was originally created by
James Tauber <jt...@jtauber.com>. For more information on the Apache
Software Foundation, please see <http://www.apache.org/>.
*/
package org.apache.fop.messaging;
import java.util.EventObject;
/**
* a container for the text and the type of a message
* MessageEvents are created by MessageHandler and can be received by any
* MessageListener, which is added to MessageHandler;
* @see org.apache.fop.MessageListener MessageListener
*
*/
public class MessageEvent extends EventObject {
public static final int LOG = 0;
public static final int ERROR = 1;
String message;
int messageType = MessageEvent.LOG;
public MessageEvent (Object source) {
super (source);
message = (String) source; //MessageHandler.getMessage()
}
/**
* retrieves the message
* @return String containing the message
*
*/
public String getMessage () {
return message;
}
/**
* sets the message type
* @param messageType the type of the message as int in the form of MessageEvent.LOG or MessageEvent.ERROR
*
*/
void setMessageType (int messageType) {
this.messageType = messageType;
}
/**
* returns the type of message as int
*
* @return messageType the type of the message as int in the form of MessageEvent.LOG or MessageEvent.ERROR
*/
public int getMessageType () {
return messageType;
}
}
1.1 xml-fop/src/org/apache/fop/messaging/MessageHandler.java
Index: MessageHandler.java
===================================================================
/*
============================================================================
The Apache Software License, Version 1.1
============================================================================
Copyright (C) 1999 The Apache Software Foundation. All rights reserved.
Redistribution and use in source and binary forms, with or without modifica-
tion, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
3. The end-user documentation included with the redistribution, if any, must
include the following acknowledgment: "This product includes software
developed by the Apache Software Foundation (http://www.apache.org/)."
Alternately, this acknowledgment may appear in the software itself, if
and wherever such third-party acknowledgments normally appear.
4. The names "Fop" and "Apache Software Foundation" must not be used to
endorse or promote products derived from this software without prior
written permission. For written permission, please contact
apache@apache.org.
5. Products derived from this software may not be called "Apache", nor may
"Apache" appear in their name, without prior written permission of the
Apache Software Foundation.
THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
APACHE SOFTWARE FOUNDATION OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLU-
DING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
This software consists of voluntary contributions made by many individuals
on behalf of the Apache Software Foundation and was originally created by
James Tauber <jt...@jtauber.com>. For more information on the Apache
Software Foundation, please see <http://www.apache.org/>.
*/
package org.apache.fop.messaging;
import java.io.*;
import java.util.*;
import javax.swing.*;
/** The class MessageHandler contains the static methods log and error which
* should be used for any end user information instead of System.out.print() or
* System.err.print(). The class defines several output methods:
* writing to the screen (default), logging to a file, creating message events and repressing all
* output. If you don't want to change the default behaviour, you should be
* happy with MessageHandler.log(message) and MessageHandler.error(message)<br>
* The class MessageHandler also supports the setting of an id. If set every message
* has as a prefix an identifying string. That way Fop probably can also be used in
* environments, where more than one Fop instance are running in same JVM.<br>
* If Fop is embedded in a gui application or for any reasons the existing
* messaging system doesn't meet the programmer's requirements, one can add
* a MessageEvent listener to MessageHandler and handle the incoming messages
* in an appropriate way. See the class DefaultMessageListener, which is a trivial
* implementation of the MessageListener.
* Here is an example how to configure MessageHandler for the DefaultMessageListener (anybody
* can provide his own listener by extending MessageListener<br>
* <code>
* MessageHandler.setOutputMethod(MessageHandler.EVENT);
* MessageHandler.addListener(new DefaultMessageListener());
* </code><br>
* This examples shows, how to redirect the messages to a log file called fop.log.
* All messages are appended to this file.
* <code>
* MessageHandler.setOutputMethod(MessageHandler.FILE);
* MessageHandler.setLogfileName("\\fop.log",true);
* </code>
*/
public class MessageHandler {
public static final int SCREEN = 0;
public static final int FILE = 1;
public static final int EVENT = 2;
public static final int NONE = 3; //this should always be the last method
private static String logfileName = "fop.log";
private static PrintWriter writer;
private static int outputMethod = SCREEN;
private static boolean fileOpened = false;
private static boolean appendToFile = true;
private static String message = "";
private static String prefix ="";
private static Vector listeners = new Vector();
private static boolean IDisSet = false;
/**
* helper class to access the message
* @return a string containing the message
*/
private static String getMessage () {
return message;
}
/**
* helper class which sets the message
* and adds a prefix which can contain
* the id of the thread which uses this messagehandler
*/
private static void setMessage (String m) {
if (IDisSet) {
message = getID() + ":" + m;
} else {
message = m;
}
}
/**
* informs the user of the message
* @param message the message for the user
*/
public static void log (String message) {
setMessage(message);
switch (outputMethod) {
case SCREEN:
System.out.print(getMessage ());
break;
case FILE:
if (fileOpened) {
writer.print(getMessage ());
writer.flush();
} else {
openFile();
writer.print(getMessage ());
writer.flush();
}
break;
case EVENT:
setMessage(message);
Enumeration enum = listeners.elements();
while (enum.hasMoreElements()) {
((MessageListener) enum.nextElement()).processMessage(new MessageEvent(getMessage()));
}
break;
case NONE:
//do nothing
default:
System.out.print(message);
}
}
/**
* convenience method which adds a return to the message
* @param message the message for the user
*/
public static void logln (String message) {
log (message+"\n");
}
/**
* error warning for the user
* @param errorMessage contains the warning string
*/
public static void error (String errorMessage) {
setMessage(errorMessage);
switch (outputMethod) {
case SCREEN:
System.err.print(getMessage());
break;
case FILE:
if (fileOpened) {
writer.print(getMessage());
writer.flush();
} else {
openFile();
writer.print(getMessage());
writer.flush();
}
break;
case EVENT:
setMessage(message);
Enumeration enum = listeners.elements();
while (enum.hasMoreElements()) {
MessageEvent messEv = new MessageEvent(getMessage());
messEv.setMessageType(MessageEvent.ERROR);
((MessageListener) enum.nextElement()).processMessage(messEv);
}
break;
case NONE:
//do nothing
default:
System.err.print(errorMessage);
}
}
/**
* convenience method which adds a return to the error message
* @param errorMessage the message for the user
*/
public static void errorln (String errorMessage) {
error (errorMessage+"\n");
}
/**
* adds a MessageListener which listens for MessageEvents
* @param MessageListener the listener to add
*/
public static void addListener(MessageListener listener) {
listeners.addElement(listener);
}
/**
* removes a MessageListener
* @param MessageListener the listener to remove
*/
public static void removeListener(MessageListener listener) {
listeners.removeElement(listener);
}
/**
* sets the output method
* @param method the output method to use, allowed values are<br>
* MessageHandler.SCREEN, MessageHandler.FILE, MessageHandler.EVENT
* MessageHandler.NONE
*/
public static void setOutputMethod (int method) {
if (method > NONE) {
MessageHandler.error("Error: Unknown output method");
} else {
outputMethod = method;
}
}
/**
* informs what output method is set
* @return the output method
*/
public static int getOutputMethod () {
return outputMethod;
}
/**
* sets the logfile name
* @param filename name of the logfile
* @param append if true, the logfile is appended
*/
public static void setLogfileName (String filename, boolean append) {
logfileName = filename;
appendToFile = append;
}
/**
* returns the logfile name
* @return String containing the logfile name
*/
public static String getLogfileName () {
return logfileName;
}
/**
* helper file which opens the file for output method FILE
*/
private static void openFile () {
try {
writer = new PrintWriter (new FileWriter (logfileName,appendToFile),true);
writer.println("\n==============================================");
fileOpened = true;
} catch (IOException ioe) {
System.err.println("Error: " + ioe);
}
}
/**
* if set to true an id string is prefixed to every message
* uses the thread info as an id for the message producer. Should be used if
* more than one instance of Fop is running in the same JVM
* this id becomes a prefix to every message
*/
private static String getID () {
return Thread.currentThread().toString() ;
}
/**
* if set to true an id string is prefixed to every message
* uses the thread info as an id for the message producer. Should be used if
* more than one instance of Fop is running in the same JVM
* this id becomes a prefix to every message
*
* @param id boolean (default is false)
*/
public static void setID (boolean id) {
IDisSet = id;
}
}
1.1 xml-fop/src/org/apache/fop/messaging/MessageListener.java
Index: MessageListener.java
===================================================================
/*
============================================================================
The Apache Software License, Version 1.1
============================================================================
Copyright (C) 1999 The Apache Software Foundation. All rights reserved.
Redistribution and use in source and binary forms, with or without modifica-
tion, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
3. The end-user documentation included with the redistribution, if any, must
include the following acknowledgment: "This product includes software
developed by the Apache Software Foundation (http://www.apache.org/)."
Alternately, this acknowledgment may appear in the software itself, if
and wherever such third-party acknowledgments normally appear.
4. The names "Fop" and "Apache Software Foundation" must not be used to
endorse or promote products derived from this software without prior
written permission. For written permission, please contact
apache@apache.org.
5. Products derived from this software may not be called "Apache", nor may
"Apache" appear in their name, without prior written permission of the
Apache Software Foundation.
THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
APACHE SOFTWARE FOUNDATION OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLU-
DING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
This software consists of voluntary contributions made by many individuals
on behalf of the Apache Software Foundation and was originally created by
James Tauber <jt...@jtauber.com>. For more information on the Apache
Software Foundation, please see <http://www.apache.org/>.
*/
package org.apache.fop.messaging;
/**
* For situations, where the messages Fop directs to the user have to be handled in some
* special way, the interface MessageListener and the class MessageEvent are provided.
* Embedding Fop into a graphical user interface could be such a scenario.<br>
* Any MessageListener listens for MessageEvents, which contain the user message and
* also the message type information (progress information or error warning).
* The class DefaultMessageListener shows an trivial implementation of MessageListener.
*/
public interface MessageListener {
void processMessage (MessageEvent event);
}