This is used as a safety net when {@link co.elastic.clients.util.ApiTypeHelper#DANGEROUS_disableRequiredPropertiesCheck(boolean)} + * is active: with the workaround enabled, deserialization can leave required reference fields as {@code null}, + * and the generated {@code serializeInternal} methods would otherwise call e.g. {@code generator.write((String) null)}, + * which throws {@link NullPointerException} in JSON-P providers such as Parsson. + * + *
See #557.
+ */
+class NullSafeJsonGenerator extends DelegatingJsonGenerator {
+
+ NullSafeJsonGenerator(JsonGenerator delegate) {
+ super(delegate);
+ }
+
+ @Override
+ public JsonGenerator write(String value) {
+ if (value == null) {
+ generator.writeNull();
+ return this;
+ }
+ return super.write(value);
+ }
+
+ @Override
+ public JsonGenerator write(BigDecimal value) {
+ if (value == null) {
+ generator.writeNull();
+ return this;
+ }
+ return super.write(value);
+ }
+
+ @Override
+ public JsonGenerator write(BigInteger value) {
+ if (value == null) {
+ generator.writeNull();
+ return this;
+ }
+ return super.write(value);
+ }
+
+ @Override
+ public JsonGenerator write(JsonValue value) {
+ if (value == null) {
+ generator.writeNull();
+ return this;
+ }
+ return super.write(value);
+ }
+}
diff --git a/java-client/src/test/java/co/elastic/clients/elasticsearch/model/BehaviorsTest.java b/java-client/src/test/java/co/elastic/clients/elasticsearch/model/BehaviorsTest.java
index dbba3a7141..1b519240cf 100644
--- a/java-client/src/test/java/co/elastic/clients/elasticsearch/model/BehaviorsTest.java
+++ b/java-client/src/test/java/co/elastic/clients/elasticsearch/model/BehaviorsTest.java
@@ -468,4 +468,38 @@ public void testDangerousDisablePropertyCheckPrimitive(){
assertTrue(healthResponse.toString()!=null);
}
}
+
+ @Test
+ public void testDangerousDisablePropertyCheckReferenceSerialization() {
+ // Repro for #557: with the workaround enabled, a null required reference
+ // field (here: clusterName, a required String) causes an NPE during
+ // re-serialization because HealthResponseBody#serializeInternal calls
+ // generator.write((String) null).
+ try (ApiTypeHelper.DisabledChecksHandle h =
+ ApiTypeHelper.DANGEROUS_disableRequiredPropertiesCheck(true)) {
+ HealthResponse healthResponse = HealthResponse.of(hr -> hr.withJson(new StringReader("{\n" +
+ // cluster_name (required) intentionally omitted
+ " \"status\" : \"green\",\n" +
+ " \"timed_out\" : false,\n" +
+ " \"number_of_nodes\" : 3,\n" +
+ " \"number_of_data_nodes\" : 2,\n" +
+ " \"active_primary_shards\" : 88,\n" +
+ " \"active_shards\" : 176,\n" +
+ " \"relocating_shards\" : 0,\n" +
+ " \"initializing_shards\" : 0,\n" +
+ " \"unassigned_shards\" : 0,\n" +
+ " \"delayed_unassigned_shards\" : 0,\n" +
+ " \"number_of_pending_tasks\" : 0,\n" +
+ " \"number_of_in_flight_fetch\" : 0,\n" +
+ " \"task_max_waiting_in_queue_millis\" : 0,\n" +
+ " \"active_shards_percent_as_number\" : 100.0\n" +
+ "}")));
+
+ // deserialization succeeds — clusterName is null because the workaround is active
+ assertTrue(healthResponse.clusterName() == null);
+
+ // round-trip currently fails with NullPointerException — this is bug #557
+ assertTrue(healthResponse.toString() != null);
+ }
+ }
}
diff --git a/java-client/src/test/java/co/elastic/clients/json/NullSafeJsonGeneratorTest.java b/java-client/src/test/java/co/elastic/clients/json/NullSafeJsonGeneratorTest.java
new file mode 100644
index 0000000000..20e56fb79a
--- /dev/null
+++ b/java-client/src/test/java/co/elastic/clients/json/NullSafeJsonGeneratorTest.java
@@ -0,0 +1,140 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package co.elastic.clients.json;
+
+import co.elastic.clients.testkit.ModelTestCase;
+import co.elastic.clients.util.ApiTypeHelper;
+import jakarta.json.JsonValue;
+import jakarta.json.stream.JsonGenerator;
+import org.junit.jupiter.api.Assumptions;
+import org.junit.jupiter.api.Test;
+
+import java.io.StringWriter;
+import java.math.BigDecimal;
+import java.math.BigInteger;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+public class NullSafeJsonGeneratorTest extends ModelTestCase {
+
+ @Test
+ public void testNullReferencesAreWrittenAsJsonNull() {
+ StringWriter writer = new StringWriter();
+ try (JsonGenerator generator = new NullSafeJsonGenerator(mapper.jsonProvider().createGenerator(writer))) {
+ generator.writeStartObject();
+
+ // writeKey + write(value) overloads with null reference values
+ generator.writeKey("string_field");
+ generator.write((String) null);
+ generator.writeKey("decimal_field");
+ generator.write((BigDecimal) null);
+ generator.writeKey("integer_field");
+ generator.write((BigInteger) null);
+ generator.writeKey("json_value_field");
+ generator.write((JsonValue) null);
+
+ // name+value overloads with null reference values — DelegatingJsonGenerator splits these into
+ // writeKey(name) + write(value), so they reach the overrides above via virtual dispatch.
+ generator.write("named_string", (String) null);
+ generator.write("named_decimal", (BigDecimal) null);
+ generator.write("named_integer", (BigInteger) null);
+ generator.write("named_json_value", (JsonValue) null);
+
+ generator.writeEnd();
+ }
+
+ assertEquals(
+ "{" +
+ "\"string_field\":null," +
+ "\"decimal_field\":null," +
+ "\"integer_field\":null," +
+ "\"json_value_field\":null," +
+ "\"named_string\":null," +
+ "\"named_decimal\":null," +
+ "\"named_integer\":null," +
+ "\"named_json_value\":null" +
+ "}",
+ writer.toString()
+ );
+ }
+
+ @Test
+ public void testNonNullValuesPassThrough() {
+ StringWriter writer = new StringWriter();
+ try (JsonGenerator generator = new NullSafeJsonGenerator(mapper.jsonProvider().createGenerator(writer))) {
+ generator.writeStartObject();
+ generator.write("string_field", "hello");
+ generator.write("int_field", 42);
+ generator.write("long_field", 10000000000L);
+ generator.write("double_field", 1.5);
+ generator.write("bool_field", true);
+ generator.write("decimal_field", new BigDecimal("3.14"));
+ generator.write("integer_field", new BigInteger("12345"));
+ generator.writeEnd();
+ }
+
+ assertEquals(
+ "{" +
+ "\"string_field\":\"hello\"," +
+ "\"int_field\":42," +
+ "\"long_field\":10000000000," +
+ "\"double_field\":1.5," +
+ "\"bool_field\":true," +
+ "\"decimal_field\":3.14," +
+ "\"integer_field\":12345" +
+ "}",
+ writer.toString()
+ );
+ }
+
+ @Test
+ public void testToJsonStringWithMapWhileWorkaroundActive() {
+ // SimpleJsonpMapper only serializes types registered in the Java client and doesn't support arbitrary Maps.
+ Assumptions.assumeFalse(jsonImpl == JsonImpl.Simple, "SimpleJsonpMapper does not support arbitrary Map serialization");
+ Map