net.logstash.logback.argument

Class DeferredStructuredArgument

java.lang.Object

net.logstash.logback.argument.DeferredStructuredArgument

All Implemented Interfaces:

StructuredArgument

public class DeferredStructuredArgument
extends Object
implements StructuredArgument

A StructuredArgument that defers the creation of another StructuredArgument until the first time its value is needed.

The value is needed in the following conditions:

• When LoggingEvent.getFormattedMessage() is called
• When LoggingEvent.prepareForDeferredProcessing() ()} is called (async appenders call this prior to dispatching the event to another thread)
• When the LoggingEvent is encoded

The deferred value will always be created in the thread calling the Logger (even if an async appender is used) since the values of structured arguments are needed when LoggingEvent.prepareForDeferredProcessing() is called (by async appenders prior to dispatching the event to another thread).

The deferred value will only be calculated once. The single value supplied by the supplier will be reused every time the structured argument is written. For example, if multiple appenders use a logstash encoder, the supplier will be invoked when the first appender encodes the marker. That same supplied value will be used when the next appender encodes the marker.

Constructor Summary

Constructors

Constructor and Description
DeferredStructuredArgument(Supplier<? extends StructuredArgument> structureArgumentSupplier)

Method Summary

Modifier and Type	Method and Description
void	writeTo(JsonGenerator generator) Writes the data associated with this argument to the given JsonGenerator.

Methods inherited from class java.lang.Object

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

Methods inherited from interface net.logstash.logback.argument.StructuredArgument

toString

Constructor Detail

DeferredStructuredArgument

public DeferredStructuredArgument(Supplier<? extends StructuredArgument> structureArgumentSupplier)

Method Detail

writeTo

public void writeTo(JsonGenerator generator)
             throws IOException

Description copied from interface: StructuredArgument

Writes the data associated with this argument to the given JsonGenerator.

Specified by:

writeTo in interface StructuredArgument

Parameters:

generator - the JsonGenerator to produce JSON content

Throws:

IOException - if an I/O error occurs