---
title: Enable Dynamic Instrumentation for Java
description: >-
  Set up Dynamic Instrumentation for Java applications to add probes and capture
  data without code changes.
breadcrumbs: >-
  Docs > APM > Application Instrumentation > Dynamic Instrumentation > Enabling
  Dynamic Instrumentation > Enable Dynamic Instrumentation for Java
---

# Enable Dynamic Instrumentation for Java

{% callout %}
# Important note for users on the following Datadog sites: app.ddog-gov.com

{% alert level="danger" %}
This product is not supported for your selected [Datadog site](https://docs.datadoghq.com/getting_started/site). ().
{% /alert %}

{% /callout %}

Dynamic Instrumentation is a feature of the Datadog tracing library that lets you add instrumentation to your application at runtime without code changes or redeployments. Follow these instructions to set up Dynamic Instrumentation for Java.

## Prerequisites{% #prerequisites %}

Before you begin, review the [Dynamic Instrumentation prerequisites](https://docs.datadoghq.com/dynamic_instrumentation/#prerequisites). Java applications also require:

- JDK version 8 or higher.
- Tracing library [`dd-java-agent.jar`](https://github.com/DataDog/dd-trace-java) version 1.34.0 or higher. See the [installation instructions](https://docs.datadoghq.com/tracing/trace_collection/dd_libraries/java/) for setup details.

## Installation{% #installation %}

1. If you don't already have APM enabled, in your Agent configuration, set the `DD_APM_ENABLED` environment variable to `true` and listening to the port `8126/TCP`.

1. Download `dd-java-agent.jar`:

   {% tab title="Wget" %}

   ```shell
   wget -O dd-java-agent.jar 'https://dtdg.co/latest-java-tracer'
   ```

   {% /tab %}

   {% tab title="cURL" %}

   ```shell
   curl -Lo dd-java-agent.jar 'https://dtdg.co/latest-java-tracer'
   ```

   {% /tab %}

   {% tab title="Dockerfile" %}

   ```dockerfile
   ADD 'https://dtdg.co/latest-java-tracer' dd-java-agent.jar
   ```

   {% /tab %}



1. Run your service with Dynamic Instrumentation enabled by setting `-Ddd.dynamic.instrumentation.enabled` flag or `DD_DYNAMIC_INSTRUMENTATION_ENABLED` environment variable to `true`. Specify `dd.service`, `dd.env`, and `dd.version` Unified Service Tags so you can filter and group your instrumentations and target active clients across these dimensions.

   {% tab title="Command arguments" %}
Example service startup command:

   ```shell
   java \
       -javaagent:dd-java-agent.jar \
       -Ddd.service=<YOUR_SERVICE> \
       -Ddd.env=<YOUR_ENVIRONMENT> \
       -Ddd.version=<YOUR_VERSION> \
       -Ddd.dynamic.instrumentation.enabled=true \
       -jar <YOUR_SERVICE>.jar <YOUR_SERVICE_FLAGS>
   ```

      {% /tab %}

   {% tab title="Environment variables" %}

   ```shell
   export DD_SERVICE=<YOUR_SERVICE>
   export DD_ENV=<YOUR_ENV>
   export DD_VERSION=<YOUR_VERSION>
   export DD_DYNAMIC_INSTRUMENTATION_ENABLED=true
   java \
       -javaagent:dd-java-agent.jar \
       -jar <YOUR_SERVICE>.jar <YOUR_SERVICE_FLAGS>
   ```

   {% /tab %}



**Note**: The `-javaagent` argument needs to be before `-jar`, adding it as a JVM option rather than an application argument. For more information, see the [Oracle documentation](https://docs.oracle.com/javase/7/docs/technotes/tools/solaris/java.html):

   ```shell
   # Good:
   java -javaagent:dd-java-agent.jar ... -jar my-service.jar -more-flags
   # Bad:
   java -jar my-service.jar -javaagent:dd-java-agent.jar ...
   ```

1. After starting your service with Dynamic Instrumentation enabled, you can start using Dynamic Instrumentation on the [APM > Dynamic Instrumentation page](https://app.datadoghq.com/dynamic-instrumentation).

## Configuration{% #configuration %}

Configure Dynamic Instrumentation using the following environment variables:

| Environment variable                 | Type    | Description                                                                                                                    |
| ------------------------------------ | ------- | ------------------------------------------------------------------------------------------------------------------------------ |
| `DD_DYNAMIC_INSTRUMENTATION_ENABLED` | Boolean | Alternate for `-Ddd.dynamic.instrumentation.enabled` argument. Set to `true` to enable Dynamic Instrumentation.                |
| `DD_SERVICE`                         | String  | The [service](https://docs.datadoghq.com/getting_started/tagging/unified_service_tagging) name, for example, `web-backend`.    |
| `DD_ENV`                             | String  | The [environment](https://docs.datadoghq.com/getting_started/tagging/unified_service_tagging) name, for example, `production`. |
| `DD_VERSION`                         | String  | The [version](https://docs.datadoghq.com/getting_started/tagging/unified_service_tagging) of your service.                     |
| `DD_TAGS`                            | String  | Tags to apply to produced data. Must be a list of `<key>:<value>` separated by commas such as: `layer:api,team:intake`.        |

## What to do next{% #what-to-do-next %}

See [Dynamic Instrumentation](https://docs.datadoghq.com/tracing/dynamic_instrumentation/) for information about adding instrumentations and browsing and indexing the data.

## Limitations{% #limitations %}

- On JDK 18 and below, classes compiled with the `-parameters` flag may fail to instrument with the error message "Method Parameters detected". Spring 6+, Spring Boot 3+, and Scala use this flag by default.

## Further reading{% #further-reading %}

- [Getting Started with Datadog Agent](https://docs.datadoghq.com/agent)