[TS+Java] Ensure we don't try to add a reference from `null`.

[ldk-java] / java_strings.py

diff --git a/java_strings.py b/java_strings.py
index bcfc1f37e4fc8a02e87d9d716020c06fb196a81d..c249c200de73f7c0b3c33a393c922bca21c9785d 100644 (file)
--- a/java_strings.py
+++ b/java_strings.py
@@ -704,7 +704,7 @@ import javax.annotation.Nullable;
         return var + ".ptr" + " = 0;"
 
     def add_ref(self, holder, referent):
-        return holder + ".ptrs_to.add(" + referent + ")"
+        return "if (" + holder + " != null) { " + holder + ".ptrs_to.add(" + referent + "); }"
 
     def fully_qualified_hu_ty_path(self, ty):
         if ty.java_fn_ty_arg.startswith("L") and ty.java_fn_ty_arg.endswith(";"):