Remove old API.

src/main/java/org/opentripplanner/framework/application/ApplicationShutdownSupport.java

@@ -13,26 +13,6 @@ public final class ApplicationShutdownSupport {
 
   private ApplicationShutdownSupport() {}
 
-  /**
-   * Attempt to add a shutdown hook. If the application is already shutting down, the shutdown hook
-   * will not be added.
-   *
-   * @return true if the shutdown hook is successfully added, false otherwise.
-   */
-  public static boolean addShutdownHook(Thread shutdownHook, String shutdownHookName) {
-    try {
-      LOG.info("Adding shutdown hook {}", shutdownHookName);
-      Runtime.getRuntime().addShutdownHook(shutdownHook);
-      return true;
-    } catch (IllegalStateException ignore) {
-      LOG.info(
-        "OTP is already shutting down, the shutdown hook {} will not be added",
-        shutdownHookName
-      );
-      return false;
-    }
-  }
-
   /**
    * Attempt to add a shutdown hook. If the application is already shutting down, the shutdown hook
    * will be executed immediately.