From 216031848e5d58da8149a24e6b6f44a7e9bbc55f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=B6rg=20Prante?= <joergprante@gmail.com>
Date: Wed, 23 Nov 2022 17:57:36 +0100
Subject: [PATCH] add convenience method

---
 gradle.properties                          |  2 +-
 src/main/java/org/xbib/marc/MarcField.java | 14 ++++++++++++++
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/gradle.properties b/gradle.properties
index 62d65f7..c813568 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -1,5 +1,5 @@
 group = org.xbib
 name = marc
-version = 2.9.7
+version = 2.9.8
 
 org.gradle.warning.mode = ALL
diff --git a/src/main/java/org/xbib/marc/MarcField.java b/src/main/java/org/xbib/marc/MarcField.java
index e108333..f496e28 100644
--- a/src/main/java/org/xbib/marc/MarcField.java
+++ b/src/main/java/org/xbib/marc/MarcField.java
@@ -451,6 +451,20 @@ public class MarcField implements Comparable<MarcField> {
             return this;
         }
 
+        /**
+         * Convenience method to add a subfield only if the value is not null.
+         * @param subfieldId the dubfield ID
+         * @param value the subfield value
+         * @return this builder
+         */
+        public Builder subfieldIfNotNull(String subfieldId, String value) {
+            if (value != null) {
+                String id = validator.validateSubfieldId(subfieldId);
+                subfields.add(new Subfield(id, value));
+            }
+            return this;
+        }
+
         /**
          * Add subfield ID without a value.
          * @param subfieldId the subfield ID