Enforce at least one value or defaultValue to always be non-null when IgnoreAbove is initialized

Author: Kubik42

server/src/main/java/org/elasticsearch/index/IgnoreAbove.java

@@ -11,8 +11,6 @@
 
 import org.elasticsearch.xcontent.XContentString;
 
-import java.util.Objects;
-
 import static org.elasticsearch.index.IndexSettings.IGNORE_ABOVE_DEFAULT_LOGSDB_INDICES;
 import static org.elasticsearch.index.IndexSettings.IGNORE_ABOVE_DEFAULT_STANDARD_INDICES;
 
@@ -33,8 +31,13 @@ public class IgnoreAbove {
     private final Integer defaultValue;
 
     public IgnoreAbove(Integer value, Integer defaultValue) {
+        if (value == null && defaultValue == null) {
+            throw new IllegalArgumentException(
+                "IgnoreAbove must be initialized with at least one non-null argument: either 'value' or 'defaultValue'"
+            );
+        }
         this.value = value;
-        this.defaultValue = Objects.requireNonNull(defaultValue);
+        this.defaultValue = defaultValue;
     }
 
     public int get() {

server/src/test/java/org/elasticsearch/index/IgnoreAboveTests.java

@@ -23,7 +23,16 @@ public void test_ignore_above_with_value_and_default() {
         assertTrue(ignoreAbove.isSet());
     }
 
-    public void test_ignore_above_with_default_only_is_valid() {
+    public void test_ignore_above_with_value_only() {
+        // given
+        IgnoreAbove ignoreAbove = IgnoreAbove.builder().value(123).build();
+
+        // when/then
+        assertEquals(123, ignoreAbove.get());
+        assertTrue(ignoreAbove.isSet());
+    }
+
+    public void test_ignore_above_with_default_only() {
         // given
         IgnoreAbove ignoreAbove = IgnoreAbove.builder().defaultValue(456).build();
 
@@ -41,14 +50,9 @@ public void test_ignore_above_with_same_value_and_default() {
         assertFalse(ignoreAbove.isSet());
     }
 
-    public void test_ignore_above_with_value_only_should_throw() {
-        // given/when/then
-        assertThrows(NullPointerException.class, () -> IgnoreAbove.builder().value(123).build());
-    }
-
     public void test_ignore_above_with_nothing_should_throw() {
         // given/when/then
-        assertThrows(NullPointerException.class, () -> IgnoreAbove.builder().build());
+        assertThrows(IllegalArgumentException.class, () -> IgnoreAbove.builder().build());
     }
 
     public void test_string_isIgnored() {