From e55aeef9039b2f28f94ea7cf091647e86f706fac Mon Sep 17 00:00:00 2001
From: Lemongrass3110 <lemongrass@kstp.at>
Date: Sat, 11 Mar 2017 23:24:33 +0100
Subject: [PATCH] Fixes beowulfe/HAP-Java#32

---
 .../beowulfe/hap/characteristics/BaseCharacteristic.java | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/main/java/com/beowulfe/hap/characteristics/BaseCharacteristic.java b/src/main/java/com/beowulfe/hap/characteristics/BaseCharacteristic.java
index a9064a10b..74835796d 100644
--- a/src/main/java/com/beowulfe/hap/characteristics/BaseCharacteristic.java
+++ b/src/main/java/com/beowulfe/hap/characteristics/BaseCharacteristic.java
@@ -68,7 +68,14 @@ public final CompletableFuture<JsonObject> toJson(int iid) {
 	 * @return a future that will complete with the JSON builder for the object.
 	 */
 	protected CompletableFuture<JsonObjectBuilder> makeBuilder(int instanceId) {
-		return getValue().exceptionally(t -> {
+		CompletableFuture<T> futureValue = getValue();
+		
+		if (futureValue == null) {
+			logger.error("Could not retrieve value "+this.getClass().getName());
+			return null;
+		}
+		
+		return futureValue.exceptionally(t -> {
 			logger.error("Could not retrieve value "+this.getClass().getName(), t);
 			return null;
 		}).thenApply(value -> {