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* to you under the Apache License, Version 2.0 (the *
* "License"); you may not use this file except in compliance *
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* *
* http://www.apache.org/licenses/LICENSE-2.0 *
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* Unless required by applicable law or agreed to in writing, *
* software distributed under the License is distributed on an *
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package org.apache.mailet;
import javax.mail.MessagingException;
import java.util.Collection;
/**
* <p>GenericMatcher implements the Matcher and MatcherConfig interfaces.</p>
* <p>GenericMatcher makes writing matchers easier. It provides simple versions of
* the lifecycle methods init and destroy and of the methods in the MatcherConfig
* interface. GenericMatcher also implements the log method, declared in the
* MatcherContext interface.</p>
*
* <p>To write a generic matcher, you need only override the abstract match method.</p>
*
* @version 1.0.0, 24/04/1999
*/
public abstract class GenericMatcher implements Matcher, MatcherConfig {
MatcherConfig config = null;
/**
* Called by the mailet container to indicate to a matcher that the
* matcher is being taken out of service.
*/
public void destroy() {
//Do nothing
}
/**
* <p>Returns a String containing the value of the named initialization
* parameter, or null if the parameter does not exist.</p>
*
* <p>This method is supplied for convenience. It gets the value of the
* named parameter from the matcher's MatcherConfig object.</p>
*
* @return String a String containing the value of the initalization parameter
*/
public String getCondition() {
return config.getCondition();
}
/**
* Returns this matcher's MatcherConfig object.
*
* @return MatcherConfig the MatcherConfig object that initialized this matcher
*/
public MatcherConfig getMatcherConfig() {
return config;
}
/**
* Returns a reference to the MailetContext in which this matcher is
* running.
*
* @return MailetContext the MailetContext object passed to this matcher by the init method
*/
public MailetContext getMailetContext() {
return getMatcherConfig().getMailetContext();
}
/**
* Returns information about the matcher, such as author, version, and
* copyright. By default, this method returns an empty string. Override
* this method to have it return a meaningful value.
*
* @return String information about this matcher, by default an empty string
*/
public String getMatcherInfo() {
return "";
}
/**
* Returns the name of this matcher instance.
*
* @return the name of this matcher instance
*/
public String getMatcherName() {
return config.getMatcherName();
}
/**
* <p>Called by the matcher container to indicate to a matcher that the
* matcher is being placed into service.</p>
*
* <p>This implementation stores the MatcherConfig object it receives from
* the matcher container for alter use. When overriding this form of the
* method, call super.init(config).</p>
*
* @param MatcherConfig config - the MatcherConfig object that contains
* configutation information for this matcher
* @throws MessagingException
* if an exception occurs that interrupts the matcher's normal operation
*/
public void init(MatcherConfig newConfig) throws MessagingException {
config = newConfig;
init();
}
/**
* <p>A convenience method which can be overridden so that there's no
* need to call super.init(config).</p>
*
* <p>Instead of overriding init(MatcherConfig), simply override this
* method and it will be called by GenericMatcher.init(MatcherConfig config).
* The MatcherConfig object can still be retrieved via getMatcherConfig().</p>
*
* @throws MatcherException
* if an exception occurs that interrupts the matcher's normal operation
*/
public void init() throws MessagingException {
//Do nothing... can be overridden
}
/**
* Writes the specified message to a matcher log file, prepended by
* the matcher's name.
*
* @param msg - a String specifying the message to be written to the log file
*/
public void log(String message) {
StringBuffer logBuffer =
new StringBuffer(256)
.append(getMatcherName())
.append(": ")
.append(message);
getMailetContext().log(logBuffer.toString());
}
/**
* Writes an explanatory message and a stack trace for a given Throwable
* exception to the matcher log file, prepended by the matcher's name.
*
* @param message - a String that describes the error or exception
* @param t - the java.lang.Throwable error or exception
*/
public void log(String message, Throwable t) {
StringBuffer logBuffer =
new StringBuffer(256)
.append(getMatcherName())
.append(": ")
.append(message);
getMailetContext().log(logBuffer.toString(), t);
}
/**
* <p>Called by the matcher container to allow the matcher to process a
* message.</p>
*
* <p>This method is declared abstract so subclasses must override it.</p>
*
* @param mail - the Mail object that contains the MimeMessage and
* routing information
* @return java.util.Collection - the recipients that the mailet container should have the
* mailet affect.
* @throws javax.mail.MessagingException - if an exception occurs that interferes with the mailet's normal operation
* occurred
*/
public abstract Collection match(Mail mail) throws MessagingException;
}
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