prepare 5.1.0 release (#210)

Author: LaunchDarklyCI

CHANGELOG.md

@@ -80,6 +80,10 @@ This is a major rewrite that introduces a cleaner API design, adds new features,
 - The Redis integration is no longer built into the main SDK library. See: https://github.com/launchdarkly/java-server-sdk-redis
 - The deprecated New Relic integration has been removed.
 
+## [4.14.3] - 2020-09-03
+### Fixed:
+- Bump SnakeYAML from 1.19 to 1.26 to address CVE-2017-18640. The SDK only parses YAML if the application has configured the SDK with a flag data file, so it's unlikely this CVE would affect SDK usage as it would require configuration and access to a local file.
+
 ## [4.14.2] - 2020-09-01
 ### Fixed:
 - Updated the version of OkHttp contained within the SDK from 3.12.10 to 3.14.9, to address multiple [known issues](https://square.github.io/okhttp/changelog_3x/) including an incompatibility with OpenJDK 8.0.252 under some conditions. ([#204](https://github.com/launchdarkly/java-server-sdk/issues/204))

src/main/java/com/launchdarkly/sdk/server/PollingProcessor.java

@@ -96,9 +96,10 @@ private void poll() {
       } else {
         if (dataSourceUpdates.init(allData.toFullDataSet())) {
           dataSourceUpdates.updateStatus(State.VALID, null);
-          logger.info("Initialized LaunchDarkly client.");
-          initialized.getAndSet(true);
-          initFuture.complete(null);
+          if (!initialized.getAndSet(true)) {
+            logger.info("Initialized LaunchDarkly client."); 
+            initFuture.complete(null);
+          }
         }
       }
     } catch (HttpErrorException e) {

src/main/java/com/launchdarkly/sdk/server/integrations/FileData.java

@@ -6,8 +6,12 @@
  * The file data source allows you to use local files as a source of feature flag state. This would
  * typically be used in a test environment, to operate using a predetermined feature flag state
  * without an actual LaunchDarkly connection. See {@link #dataSource()} for details.
- * 
+ * <p>
+ * This is different from {@link TestData}, which allows you to simulate flag configurations
+ * programmatically rather than using a file.
+ *
  * @since 4.12.0
+ * @see TestData
  */
 public abstract class FileData {
   /**