public class

SMTPAppender

extends AppenderSkeleton
implements UnrecognizedElementHandler
java.lang.Object
   ↳ org.apache.log4j.AppenderSkeleton
     ↳ org.apache.log4j.net.SMTPAppender

Class Overview

Send an e-mail when a specific logging event occurs, typically on errors or fatal errors.

The number of logging events delivered in this e-mail depend on the value of BufferSize option. The SMTPAppender keeps only the last BufferSize logging events in its cyclic buffer. This keeps memory requirements at a reasonable level while still delivering useful application context. By default, an email message will be sent when an ERROR or higher severity message is appended. The triggering criteria can be modified by setting the evaluatorClass property with the name of a class implementing TriggeringEventEvaluator, setting the evaluator property with an instance of TriggeringEventEvaluator or nesting a triggeringPolicy element where the specified class implements TriggeringEventEvaluator. This class has implemented UnrecognizedElementHandler since 1.2.15. Since 1.2.16, SMTP over SSL is supported by setting SMTPProtocol to "smpts".

Summary

Fields
protected CyclicBuffer cb
protected TriggeringEventEvaluator evaluator
protected Message msg
[Expand]
Inherited Fields
From class org.apache.log4j.AppenderSkeleton
Public Constructors
SMTPAppender()
The default constructor will instantiate the appender with a TriggeringEventEvaluator that will trigger on events with level ERROR or higher.
SMTPAppender(TriggeringEventEvaluator evaluator)
Use evaluator passed as parameter as the TriggeringEventEvaluator for this SMTPAppender.
Public Methods
void activateOptions()
Activate the specified options, such as the smtp host, the recipient, from, etc.
void append(LoggingEvent event)
Perform SMTPAppender specific appending actions, mainly adding the event to a cyclic buffer and checking if the event triggers an e-mail to be sent.
synchronized void close()
String getBcc()
Get the bcc recipient addresses.
int getBufferSize()
Returns value of the BufferSize option.
String getCc()
Get the cc recipient addresses.
final TriggeringEventEvaluator getEvaluator()
Get triggering evaluator.
String getEvaluatorClass()
Returns value of the EvaluatorClass option.
String getFrom()
Returns value of the From option.
boolean getLocationInfo()
Returns value of the LocationInfo option.
String getReplyTo()
Get the reply addresses.
boolean getSMTPDebug()
Get SMTP debug.
String getSMTPHost()
Returns value of the SMTPHost option.
String getSMTPPassword()
Get SMTP password.
final int getSMTPPort()
Get port.
final String getSMTPProtocol()
Get transport protocol.
String getSMTPUsername()
Get SMTP user name.
final boolean getSendOnClose()
Get sendOnClose.
String getSubject()
Returns value of the Subject option.
String getTo()
Returns value of the To option.
boolean parseUnrecognizedElement(Element element, Properties props)
Called to inform a configured object when an unrecognized child element is encountered.
boolean requiresLayout()
The SMTPAppender requires a layout.
void setBcc(String addresses)
Set the bcc recipient addresses.
void setBufferSize(int bufferSize)
The BufferSize option takes a positive integer representing the maximum number of logging events to collect in a cyclic buffer.
void setCc(String addresses)
Set the cc recipient addresses.
final void setEvaluator(TriggeringEventEvaluator trigger)
Sets triggering evaluator.
void setEvaluatorClass(String value)
The EvaluatorClass option takes a string value representing the name of the class implementing the TriggeringEventEvaluator interface.
void setFrom(String from)
The From option takes a string value which should be a e-mail address of the sender.
void setLocationInfo(boolean locationInfo)
The LocationInfo option takes a boolean value.
void setReplyTo(String addresses)
Set the e-mail addresses to which replies should be directed.
void setSMTPDebug(boolean debug)
Setting the SmtpDebug option to true will cause the mail session to log its server interaction to stdout.
void setSMTPHost(String smtpHost)
The SMTPHost option takes a string value which should be a the host name of the SMTP server that will send the e-mail message.
void setSMTPPassword(String password)
The SmtpPassword option takes a string value which should be the password required to authenticate against the mail server.
final void setSMTPPort(int val)
Set port.
final void setSMTPProtocol(String val)
Set transport protocol.
void setSMTPUsername(String username)
The SmtpUsername option takes a string value which should be the username required to authenticate against the mail server.
final void setSendOnClose(boolean val)
Set sendOnClose.
void setSubject(String subject)
The Subject option takes a string value which should be a the subject of the e-mail message.
void setTo(String to)
The To option takes a string value which should be a comma separated list of e-mail address of the recipients.
Protected Methods
void addressMessage(Message msg)
Address message.
boolean checkEntryConditions()
This method determines if there is a sense in attempting to append.
Session createSession()
Create mail session.
String formatBody()
Layout body of email message.
void sendBuffer()
Send the contents of the cyclic buffer as an e-mail message.
[Expand]
Inherited Methods
From class org.apache.log4j.AppenderSkeleton
From class java.lang.Object
From interface org.apache.log4j.Appender
From interface org.apache.log4j.spi.OptionHandler
From interface org.apache.log4j.xml.UnrecognizedElementHandler

Fields

protected CyclicBuffer cb

protected TriggeringEventEvaluator evaluator

protected Message msg

Public Constructors

public SMTPAppender ()

The default constructor will instantiate the appender with a TriggeringEventEvaluator that will trigger on events with level ERROR or higher.

public SMTPAppender (TriggeringEventEvaluator evaluator)

Use evaluator passed as parameter as the TriggeringEventEvaluator for this SMTPAppender.

Public Methods

public void activateOptions ()

Activate the specified options, such as the smtp host, the recipient, from, etc.

public void append (LoggingEvent event)

Perform SMTPAppender specific appending actions, mainly adding the event to a cyclic buffer and checking if the event triggers an e-mail to be sent.

public synchronized void close ()

public String getBcc ()

Get the bcc recipient addresses.

Returns
  • recipient addresses as comma separated string, may be null.

public int getBufferSize ()

Returns value of the BufferSize option.

public String getCc ()

Get the cc recipient addresses.

Returns
  • recipient addresses as comma separated string, may be null.

public final TriggeringEventEvaluator getEvaluator ()

Get triggering evaluator.

Returns
  • triggering event evaluator.

public String getEvaluatorClass ()

Returns value of the EvaluatorClass option.

public String getFrom ()

Returns value of the From option.

public boolean getLocationInfo ()

Returns value of the LocationInfo option.

public String getReplyTo ()

Get the reply addresses.

Returns
  • reply addresses as comma separated string, may be null.

public boolean getSMTPDebug ()

Get SMTP debug.

Returns
  • SMTP debug flag.

public String getSMTPHost ()

Returns value of the SMTPHost option.

public String getSMTPPassword ()

Get SMTP password.

Returns
  • SMTP password, may be null.

public final int getSMTPPort ()

Get port.

Returns
  • port, negative values indicate use of default ports for protocol.

public final String getSMTPProtocol ()

Get transport protocol. Typically null or "smtps".

Returns
  • transport protocol, may be null.

public String getSMTPUsername ()

Get SMTP user name.

Returns
  • SMTP user name, may be null.

public final boolean getSendOnClose ()

Get sendOnClose.

Returns
  • if true all buffered logging events will be sent when the appender is closed.

public String getSubject ()

Returns value of the Subject option.

public String getTo ()

Returns value of the To option.

public boolean parseUnrecognizedElement (Element element, Properties props)

Called to inform a configured object when an unrecognized child element is encountered.

Parameters
element element, may not be null.
props properties in force, may be null.
Returns
  • true if configured object recognized the element
Throws
Exception

public boolean requiresLayout ()

The SMTPAppender requires a layout.

public void setBcc (String addresses)

Set the bcc recipient addresses.

Parameters
addresses recipient addresses as comma separated string, may be null.

public void setBufferSize (int bufferSize)

The BufferSize option takes a positive integer representing the maximum number of logging events to collect in a cyclic buffer. When the BufferSize is reached, oldest events are deleted as new events are added to the buffer. By default the size of the cyclic buffer is 512 events.

public void setCc (String addresses)

Set the cc recipient addresses.

Parameters
addresses recipient addresses as comma separated string, may be null.

public final void setEvaluator (TriggeringEventEvaluator trigger)

Sets triggering evaluator.

Parameters
trigger triggering event evaluator.

public void setEvaluatorClass (String value)

The EvaluatorClass option takes a string value representing the name of the class implementing the TriggeringEventEvaluator interface. A corresponding object will be instantiated and assigned as the triggering event evaluator for the SMTPAppender.

public void setFrom (String from)

The From option takes a string value which should be a e-mail address of the sender.

public void setLocationInfo (boolean locationInfo)

The LocationInfo option takes a boolean value. By default, it is set to false which means there will be no effort to extract the location information related to the event. As a result, the layout that formats the events as they are sent out in an e-mail is likely to place the wrong location information (if present in the format).

Location information extraction is comparatively very slow and should be avoided unless performance is not a concern.

public void setReplyTo (String addresses)

Set the e-mail addresses to which replies should be directed.

Parameters
addresses reply addresses as comma separated string, may be null.

public void setSMTPDebug (boolean debug)

Setting the SmtpDebug option to true will cause the mail session to log its server interaction to stdout. This can be useful when debuging the appender but should not be used during production because username and password information is included in the output.

Parameters
debug debug flag.

public void setSMTPHost (String smtpHost)

The SMTPHost option takes a string value which should be a the host name of the SMTP server that will send the e-mail message.

public void setSMTPPassword (String password)

The SmtpPassword option takes a string value which should be the password required to authenticate against the mail server.

Parameters
password password, may be null.

public final void setSMTPPort (int val)

Set port.

Parameters
val port, negative values indicate use of default ports for protocol.

public final void setSMTPProtocol (String val)

Set transport protocol. Typically null or "smtps".

Parameters
val transport protocol, may be null.

public void setSMTPUsername (String username)

The SmtpUsername option takes a string value which should be the username required to authenticate against the mail server.

Parameters
username user name, may be null.

public final void setSendOnClose (boolean val)

Set sendOnClose.

Parameters
val if true all buffered logging events will be sent when appender is closed.

public void setSubject (String subject)

The Subject option takes a string value which should be a the subject of the e-mail message.

public void setTo (String to)

The To option takes a string value which should be a comma separated list of e-mail address of the recipients.

Protected Methods

protected void addressMessage (Message msg)

Address message.

Parameters
msg message, may not be null.
Throws
MessagingException thrown if error addressing message.

protected boolean checkEntryConditions ()

This method determines if there is a sense in attempting to append.

It checks whether there is a set output target and also if there is a set layout. If these checks fail, then the boolean value false is returned.

protected Session createSession ()

Create mail session.

Returns
  • mail session, may not be null.

protected String formatBody ()

Layout body of email message.

protected void sendBuffer ()

Send the contents of the cyclic buffer as an e-mail message.