From e379c8b8c09de73d1f098664283f8c38da58bc39 Mon Sep 17 00:00:00 2001
From: Eduard Tudenhoefner <etudenhoefner@gmail.com>
Date: Wed, 30 Nov 2022 11:22:28 +0100
Subject: [PATCH] Core: Fix NPE in CloseableIterable.close()

---
 .../java/org/apache/iceberg/io/CloseableIterable.java     | 4 +++-
 .../java/org/apache/iceberg/io/TestCloseableIterable.java | 8 ++++++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/api/src/main/java/org/apache/iceberg/io/CloseableIterable.java b/api/src/main/java/org/apache/iceberg/io/CloseableIterable.java
index 71e99aaeb468..06323612a178 100644
--- a/api/src/main/java/org/apache/iceberg/io/CloseableIterable.java
+++ b/api/src/main/java/org/apache/iceberg/io/CloseableIterable.java
@@ -279,7 +279,9 @@ public boolean hasNext() {
       @Override
       public void close() throws IOException {
         if (!closed) {
-          currentIterable.close();
+          if (null != currentIterable) {
+            currentIterable.close();
+          }
           this.closed = true;
           this.currentIterator = null;
           this.currentIterable = null;
diff --git a/api/src/test/java/org/apache/iceberg/io/TestCloseableIterable.java b/api/src/test/java/org/apache/iceberg/io/TestCloseableIterable.java
index df4edb035861..0c001c53180b 100644
--- a/api/src/test/java/org/apache/iceberg/io/TestCloseableIterable.java
+++ b/api/src/test/java/org/apache/iceberg/io/TestCloseableIterable.java
@@ -201,6 +201,14 @@ public CloseableIterator<Integer> iterator() {
     Assertions.assertThat(counter.get()).isEqualTo(items.size());
   }
 
+  @Test
+  public void concatIterablesWithIterator() throws IOException {
+    CloseableIterable<Object> closeableIterable = CloseableIterable.concat(Collections.emptyList());
+    closeableIterable.iterator();
+    // shouldn't throw a NPE
+    closeableIterable.close();
+  }
+
   @Test
   public void count() {
     Counter counter = new DefaultMetricsContext().counter("x");