---
title: "LaunchDarkly"
description: "Learn how to use Sentry with LaunchDarkly in your Java app."
url: https://docs.sentry.io/platforms/java/guides/servlet/integrations/launchdarkly/
---

# LaunchDarkly | Sentry for Servlet

The [LaunchDarkly](https://launchdarkly.com/) integration tracks feature flag evaluations produced by the LaunchDarkly SDK. These evaluations are held in memory and are sent to Sentry on error and transaction events. **At the moment, we only support boolean flag evaluations.**

## [Install](https://docs.sentry.io/platforms/java/guides/servlet/integrations/launchdarkly.md#install)

To install use:

```groovy
implementation 'io.sentry:sentry-launchdarkly-server:8.27.0'
```

For other dependency managers, check out the [central Maven repository](https://search.maven.org/artifact/io.sentry/sentry-launchdarkly-server).

Before using this integration, you need to install and instrument the [LaunchDarkly Java SDK](https://docs.launchdarkly.com/sdk/server-side/java) in your app.

## [Configure](https://docs.sentry.io/platforms/java/guides/servlet/integrations/launchdarkly.md#configure)

Add `SentryLaunchDarklyServerHook` to your LaunchDarkly setup:

```java
import com.launchdarkly.sdk.LDContext;
import com.launchdarkly.sdk.server.Components;
import com.launchdarkly.sdk.server.LDClient;
import com.launchdarkly.sdk.server.LDConfig;

import io.sentry.launchdarkly.server.SentryLaunchDarklyServerHook;


LDConfig config = new LDConfig.Builder()
    .hooks(Components.hooks()

        .setHooks(Arrays.asList(new SentryLaunchDarklyServerHook())))

    .build();
LDClient launchDarklyClient = new LDClient("sdk-key", config);
```

## [Verify](https://docs.sentry.io/platforms/java/guides/servlet/integrations/launchdarkly.md#verify)

The integration is tested by evaluating a feature flag using your LaunchDarkly SDK before capturing an exception.

```java
import io.sentry.Sentry;


boolean flagValue = launchDarklyClient.boolVariation("test-flag", context, false);

Sentry.captureException(new Exception("Something went wrong!"));
```

Visit the Sentry website and confirm that your error event has recorded the feature flag "test-flag" and its value "false".

##### Next Steps

* **Track feature flag evaluations in other parts of your codebase.** If needed, you can set up evaluation tracking for more than one SDK. [Read the docs](https://docs.sentry.io/product/issues/issue-details/feature-flags.md#set-up-evaluation-tracking) to learn more.
* **Set up your change tracking webhook.** In order to take full advantage of the feature flag capabilities Sentry offers there is an additional setup step needed. Your feature flag provider needs to notify Sentry when a feature flag definition has changed. A Sentry webhook URL can be registered with your provider. Learn [how](https://docs.sentry.io/product/issues/issue-details/feature-flags.md#set-up-change-tracking).