# Log4j2 Autoconfigure Integration
This module provides a Log4j2 `ContextDataProvider` that injects trace context from active spans
into log context.
To use it, add the module to your application's runtime classpath.
Replace `OPENTELEMETRY_VERSION` with the latest
stable [release](https://search.maven.org/search?q=g:io.opentelemetry.instrumentation).
**Maven**
```xml
io.opentelemetry.instrumentation
opentelemetry-log4j-2.16-autoconfigure
OPENTELEMETRY_VERSION
```
**Gradle**
```kotlin
dependencies {
runtimeOnly("io.opentelemetry.instrumentation:opentelemetry-log4j-2.16-autoconfigure:OPENTELEMETRY_VERSION")
}
```
`OpenTelemetryContextDataProvider` implements the Log4j2 `ContextDataProvider` SPI, and injects the
trace ID and span ID from an active span into
Log4j's [context data](https://logging.apache.org/log4j/2.x/manual/thread-context.html).
Log4j will automatically pick up the integration when you include this module. The following keys
will be added to the context when a log statement is made when a span is active:
- `trace_id`
- `span_id`
- `trace_flags`
You can use these keys when defining an appender in your `log4j.xml` configuration, for example:
```xml
```