Package org.apache.logging.log4j.core.impl

Class MementoMessage

java.lang.Object

org.apache.logging.log4j.core.impl.MementoMessage

All Implemented Interfaces:

java.io.Serializable, Message, StringBuilderFormattable

public final class MementoMessage
extends java.lang.Object
implements Message, StringBuilderFormattable

Consider this class private. MementoMessage is intended to be used when we need to make an immutable copy of a Message without forgetting the original Message.getFormat() and Message.getParameters() values.

Since:

3.0

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
private java.lang.String	format
private java.lang.String	formattedMessage
private java.lang.Object[]	parameters

Constructor Summary

Constructors

Constructor	Description
MementoMessage(java.lang.String formattedMessage, java.lang.String format, java.lang.Object[] parameters)

Method Summary

Modifier and Type	Method	Description
void	formatTo(java.lang.StringBuilder buffer)	Writes a text representation of this object into the specified StringBuilder, ideally without allocating temporary objects.
java.lang.String	getFormat()	Gets the format portion of the Message.
java.lang.String	getFormattedMessage()	Gets the Message formatted as a String.
java.lang.Object[]	getParameters()	Gets parameter values, if any.
java.lang.Throwable	getThrowable()	Always returns null.
java.lang.String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

formattedMessage

private final java.lang.String formattedMessage

format

private final java.lang.String format

parameters

private final java.lang.Object[] parameters

Constructor Detail

MementoMessage

public MementoMessage(java.lang.String formattedMessage,
                      java.lang.String format,
                      java.lang.Object[] parameters)

Method Detail

getFormattedMessage

public java.lang.String getFormattedMessage()

Description copied from interface: Message

Gets the Message formatted as a String. Each Message implementation determines the appropriate way to format the data encapsulated in the Message. Messages that provide more than one way of formatting the Message will implement MultiformatMessage.

When configured to log asynchronously, this method is called before the Message is queued, unless this message implements ReusableMessage or is annotated with AsynchronouslyFormattable. This gives the Message implementation class a chance to create a formatted message String with the current value of any mutable objects. The intention is that the Message implementation caches this formatted message and returns it on subsequent calls. (See LOG4J2-763.)

When logging synchronously, this method will not be called for Messages that implement the StringBuilderFormattable interface: instead, the formatTo(StringBuilder) method will be called so the Message can format its contents without creating intermediate String objects.

Specified by:

getFormattedMessage in interface Message

Returns:

The message String.

getFormat

public java.lang.String getFormat()

Description copied from interface: Message

Gets the format portion of the Message.

Specified by:

getFormat in interface Message

Returns:

The message format. Some implementations, such as ParameterizedMessage, will use this as the message "pattern". Other Messages may simply return an empty String. TODO Do all messages have a format? What syntax? Using a Formatter object could be cleaner. (RG) In SimpleMessage the format is identical to the formatted message. In ParameterizedMessage and StructuredDataMessage it is not. It is up to the Message implementer to determine what this method will return. A Formatter is inappropriate as this is very specific to the Message implementation so it isn't clear to me how having a Formatter separate from the Message would be cleaner.

getParameters

public java.lang.Object[] getParameters()

Description copied from interface: Message

Gets parameter values, if any.

Specified by:

getParameters in interface Message

Returns:

An array of parameter values or null.

getThrowable

public java.lang.Throwable getThrowable()

Always returns null.

Specified by:

getThrowable in interface Message

Returns:

null

formatTo

public void formatTo(java.lang.StringBuilder buffer)

Description copied from interface: StringBuilderFormattable

Writes a text representation of this object into the specified StringBuilder, ideally without allocating temporary objects.

Specified by:

formatTo in interface StringBuilderFormattable

Parameters:

buffer - the StringBuilder to write into

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object