From 5cd203d3668d8e720244686433cbd44d614f0343 Mon Sep 17 00:00:00 2001
From: Craig Raw <craigraw@gmail.com>
Date: Thu, 23 Jul 2020 14:13:57 +0200
Subject: [PATCH] fix for clear witness

---
 .../com/sparrowwallet/drongo/protocol/TransactionInput.java    | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/main/java/com/sparrowwallet/drongo/protocol/TransactionInput.java b/src/main/java/com/sparrowwallet/drongo/protocol/TransactionInput.java
index 92f12ba..3cef84e 100644
--- a/src/main/java/com/sparrowwallet/drongo/protocol/TransactionInput.java
+++ b/src/main/java/com/sparrowwallet/drongo/protocol/TransactionInput.java
@@ -101,9 +101,10 @@ public class TransactionInput extends ChildMessage {
     }
 
     public void setWitness(TransactionWitness witness) {
+        int newLength = witness != null ? witness.getLength() : 0;
         int existingLength = getWitness() != null ? getWitness().getLength() : 0;
         if(getParent() != null) {
-            getParent().adjustLength(witness.getLength() - existingLength);
+            getParent().adjustLength(newLength - existingLength);
         }
 
         this.witness = witness;