Reject non zero offset

Signed-off-by: Robert Kruszewski <github@robertk.io>

Author: robert3005

c/src/main/java/org/apache/arrow/c/ArrayImporter.java

@@ -83,6 +83,11 @@ private void importChild(ArrayImporter parent, ArrowArray src) {
   }
 
   private void doImport(ArrowArray.Snapshot snapshot) {
+    checkState(
+        snapshot.offset == 0,
+        "ArrowArray struct has non-zero offset (%s), which is not supported",
+        snapshot.offset);
+
     // First import children (required for reconstituting parent array data)
     long[] children =
         NativeUtil.toJavaArray(snapshot.children, checkedCastToInt(snapshot.n_children));

c/src/main/java/org/apache/arrow/c/Data.java

@@ -35,7 +35,8 @@
 /**
  * Functions for working with the C data interface.
  *
- * <p>This API is EXPERIMENTAL. Note that currently only 64bit systems are supported.
+ * <p>This API is EXPERIMENTAL. Note that currently only 64bit systems are supported. Importing
+ * {@link ArrowArray ArrowArrays} with a non-zero offset is not supported.
  */
 public final class Data {
 

c/src/test/java/org/apache/arrow/c/RoundtripTest.java

@@ -1051,6 +1051,27 @@ public void testImportReleasedArray() {
     }
   }
 
+  @Test
+  public void testImportArrayWithNonZeroOffset() {
+    try (IntVector source = new IntVector("source", allocator);
+        IntVector destination = new IntVector("destination", allocator);
+        ArrowArray array = ArrowArray.allocateNew(allocator)) {
+      setVector(source, 1, 2, 3);
+      Data.exportVector(allocator, source, null, array);
+
+      ArrowArray.Snapshot snapshot = array.snapshot();
+      snapshot.offset = 1;
+      array.save(snapshot);
+
+      Exception e =
+          assertThrows(
+              IllegalStateException.class,
+              () -> Data.importIntoVector(allocator, array, destination, null));
+      assertEquals(
+          "ArrowArray struct has non-zero offset (1), which is not supported", e.getMessage());
+    }
+  }
+
   @Test
   public void testArrayStructReuse() {
     // Consumer allocates empty structures

docs/source/cdata.rst

@@ -22,6 +22,11 @@ C Data Interface
 Arrow supports exchanging data without copying or serialization within the same process
 through :external+arrow:ref:`c-data-interface`, even between different language runtimes.
 
+.. note::
+
+   The Arrow Java C Data Interface implementation does not support importing arrays with
+   a non-zero offset.
+
 Java to Python
 --------------