Serialization optimization for DDB enhanced Client

services-custom/dynamodb-enhanced/src/main/java/software/amazon/awssdk/enhanced/dynamodb/internal/document/DefaultEnhancedDocument.java

@@ -17,8 +17,6 @@
 
 import static java.util.Collections.unmodifiableList;
 import static java.util.Collections.unmodifiableMap;
-import static software.amazon.awssdk.enhanced.dynamodb.internal.document.JsonStringFormatHelper.addEscapeCharacters;
-import static software.amazon.awssdk.enhanced.dynamodb.internal.document.JsonStringFormatHelper.stringValue;
 
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -193,7 +191,7 @@ public String getJson(String attributeName) {
         if (attributeValue == null) {
             return null;
         }
-        return stringValue(JSON_ATTRIBUTE_CONVERTER.transformTo(attributeValue));
+        return DocumentJsonSerializer.serializeSingleAttributeValue(attributeValue);
     }
 
     @Override
@@ -230,12 +228,7 @@ public String toJson() {
         if (nonAttributeValueMap.isEmpty()) {
             return "{}";
         }
-        return attributeValueMap.getValue().entrySet().stream()
-                                .map(entry -> "\""
-                                              + addEscapeCharacters(entry.getKey())
-                                              + "\":"
-                                              + stringValue(JSON_ATTRIBUTE_CONVERTER.transformTo(entry.getValue())))
-                                .collect(Collectors.joining(",", "{", "}"));
+        return DocumentJsonSerializer.serializeAttributeValueMap(attributeValueMap.getValue());
     }
 
     @Override

services-custom/dynamodb-enhanced/src/main/java/software/amazon/awssdk/enhanced/dynamodb/internal/document/DocumentJsonSerializer.java

@@ -0,0 +1,121 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License").
+ * You may not use this file except in compliance with the License.
+ * A copy of the License is located at
+ *
+ *  http://aws.amazon.com/apache2.0
+ *
+ * or in the "license" file accompanying this file. This file 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 software.amazon.awssdk.enhanced.dynamodb.internal.document;
+
+import java.io.IOException;
+import java.io.OutputStream;
+import java.nio.charset.StandardCharsets;
+import java.util.Map;
+import software.amazon.awssdk.annotations.SdkInternalApi;
+import software.amazon.awssdk.core.SdkBytes;
+import software.amazon.awssdk.protocols.json.SdkJsonGenerator;
+import software.amazon.awssdk.services.dynamodb.model.AttributeValue;
+import software.amazon.awssdk.thirdparty.jackson.core.JsonFactory;
+import software.amazon.awssdk.thirdparty.jackson.core.JsonGenerator;
+
+/**
+ * JSON serializer for DynamoDB Enhanced Client document operations.
+ */
+@SdkInternalApi
+final class DocumentJsonSerializer {
+    private static final JsonFactory JSON_FACTORY = new JsonFactory() {
+        @Override
+        public JsonGenerator createGenerator(OutputStream out) throws IOException {
+            return super.createGenerator(out).enable(JsonGenerator.Feature.COMBINE_UNICODE_SURROGATES_IN_UTF8);
+        }
+    };
+
+    private DocumentJsonSerializer() {
+    }
+
+    public static String serializeAttributeValueMap(Map<String, AttributeValue> map) {
+        SdkJsonGenerator jsonGen = new SdkJsonGenerator(JSON_FACTORY, "application/json");
+
+        jsonGen.writeStartObject();
+        map.forEach((key, value) -> {
+            jsonGen.writeFieldName(key);
+            serializeAttributeValue(jsonGen, value);
+        });
+        jsonGen.writeEndObject();
+
+        return new String(jsonGen.getBytes(), StandardCharsets.UTF_8);
+    }
+
+    public static String serializeSingleAttributeValue(AttributeValue av) {
+        SdkJsonGenerator jsonGen = new SdkJsonGenerator(JSON_FACTORY, "application/json");
+        serializeAttributeValue(jsonGen, av);
+        return new String(jsonGen.getBytes(), StandardCharsets.UTF_8);
+    }
+
+    public static void serializeAttributeValue(SdkJsonGenerator generator, AttributeValue av) {
+        switch (av.type()) {
+            case NUL:
+                generator.writeNull();
+                break;
+            case S:
+                generator.writeValue(av.s());
+                break;
+            case N:
+                generator.writeNumber(av.n());
+                break;
+            case BOOL:
+                generator.writeValue(av.bool());
+                break;
+            case B:
+                generator.writeValue(av.b().asByteBuffer());
+                break;
+            case L:
+                generator.writeStartArray();
+                for (AttributeValue item : av.l()) {
+                    serializeAttributeValue(generator, item);
+                }
+                generator.writeEndArray();
+                break;
+            case M:
+                generator.writeStartObject();
+                for (Map.Entry<String, AttributeValue> entry : av.m().entrySet()) {
+                    generator.writeFieldName(entry.getKey());
+                    serializeAttributeValue(generator, entry.getValue());
+                }
+                generator.writeEndObject();
+                break;
+            case SS:
+                generator.writeStartArray();
+                for (String s : av.ss()) {
+                    generator.writeValue(s);
+                }
+                generator.writeEndArray();
+                break;
+            case NS:
+                generator.writeStartArray();
+                for (String n : av.ns()) {
+                    generator.writeNumber(n);
+                }
+                generator.writeEndArray();
+                break;
+            case BS:
+                generator.writeStartArray();
+                for (SdkBytes b : av.bs()) {
+                    generator.writeValue(b.asByteBuffer());
+                }
+                generator.writeEndArray();
+                break;
+            default:
+                throw new IllegalArgumentException("Unsupported AttributeValue type: " + av.type());
+        }
+    }
+
+}

services-custom/dynamodb-enhanced/src/test/java/software/amazon/awssdk/enhanced/dynamodb/document/DocumentTableSchemaTest.java

@@ -31,6 +31,7 @@
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.ArgumentsSource;
 import software.amazon.awssdk.enhanced.dynamodb.AttributeValueType;
+import software.amazon.awssdk.enhanced.dynamodb.DefaultAttributeConverterProvider;
 import software.amazon.awssdk.enhanced.dynamodb.EnhancedType;
 import software.amazon.awssdk.enhanced.dynamodb.TableMetadata;
 import software.amazon.awssdk.enhanced.dynamodb.converters.document.CustomAttributeForDocumentConverterProvider;

services-custom/dynamodb-enhanced/src/test/java/software/amazon/awssdk/enhanced/dynamodb/document/EnhancedDocumentTest.java

@@ -24,6 +24,7 @@
 import static software.amazon.awssdk.enhanced.dynamodb.document.EnhancedDocumentTestData.testDataInstance;
 
 import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import java.math.BigDecimal;
 import java.time.LocalDate;
@@ -52,6 +53,8 @@
 
 class EnhancedDocumentTest {
 
+    ObjectMapper mapper = new ObjectMapper();
+
     private static Stream<Arguments> escapeDocumentStrings() {
         char c = 0x0a;
         return Stream.of(
@@ -496,4 +499,184 @@ void error_when_usingClassGetPut_for_CollectionValues(){
                                                 () -> EnhancedDocument.builder().build().get("listKey" , List.class))
                                             .withMessage("Values of type List are not supported by this API, please use the getList API instead");
     }
+
+    @Test
+    void toJson_numberFormatting_veryLargeNumbers() throws JsonProcessingException {
+        EnhancedDocument doc = EnhancedDocument.builder()
+            .attributeConverterProviders(defaultProvider())
+            .putNumber("longMax", Long.MAX_VALUE)
+            .putNumber("longMin", Long.MIN_VALUE)
+            .putNumber("doubleMax", Double.MAX_VALUE)
+            .putNumber("scientific", 1.23e+100)
+            .putNumber("manyDecimals", 1.123456789012345)
+            .build();
+
+        String json = doc.toJson();
+        JsonNode actual = mapper.readTree(json);
+        JsonNode expected = mapper.readTree("{\"longMax\":9223372036854775807,\"longMin\":-9223372036854775808,"
+                                            + "\"doubleMax\":1.7976931348623157E308,\"scientific\":1.23E100,"
+                                            + "\"manyDecimals\":1.123456789012345}");
+        assertThat(expected).isEqualTo(actual);
+    }
+
+    @Test
+    void toJson_numberFormatting_trailingZeros() throws JsonProcessingException {
+        EnhancedDocument doc = EnhancedDocument.builder()
+            .attributeConverterProviders(defaultProvider())
+            .putNumber("twoPointZero", 2.0)
+            .putNumber("tenPointZeroZero", 10.00)
+            .build();
+
+        String json = doc.toJson();
+        JsonNode actual = mapper.readTree(json);
+        JsonNode expected = mapper.readTree("{\"twoPointZero\":2.0,\"tenPointZeroZero\":10.0}");
+        assertThat(expected).isEqualTo(actual);
+    }
+
+    @Test
+    void toJson_stringEscaping_allControlCharacters() throws JsonProcessingException {
+        EnhancedDocument doc = EnhancedDocument.builder()
+            .attributeConverterProviders(defaultProvider())
+            .putString("allEscapes", "line1\nline2\ttab\"quote\\backslash\r\f")
+            .build();
+
+        String json = doc.toJson();
+        JsonNode actual = mapper.readTree(json);
+        JsonNode expected = mapper.readTree("{\"allEscapes\":\"line1\\nline2\\ttab\\\"quote\\\\backslash\\r\\f\"}");
+        assertThat(expected).isEqualTo(actual);
+    }
+
+    @Test
+    void toJson_stringEscaping_forwardSlash() throws JsonProcessingException {
+        EnhancedDocument doc = EnhancedDocument.builder()
+            .attributeConverterProviders(defaultProvider())
+            .putString("slash", "path/to/resource")
+            .build();
+
+        String json = doc.toJson();
+        JsonNode actual = mapper.readTree(json);
+        JsonNode expected = mapper.readTree("{\"slash\":\"path/to/resource\"}");
+        assertThat(expected).isEqualTo(actual);
+    }
+
+    @Test
+    void toJson_emptyString() throws JsonProcessingException {
+        EnhancedDocument doc = EnhancedDocument.builder()
+            .attributeConverterProviders(defaultProvider())
+            .putString("empty", "")
+            .build();
+
+        String json = doc.toJson();
+        JsonNode actual = mapper.readTree(json);
+        JsonNode expected = mapper.readTree("{\"empty\":\"\"}");
+        assertThat(expected).isEqualTo(actual);
+    }
+
+    @Test
+    void toJson_bytesEncoding_emptyBytes() throws JsonProcessingException {
+        EnhancedDocument doc = EnhancedDocument.builder()
+            .attributeConverterProviders(defaultProvider())
+            .putBytes("empty", SdkBytes.fromByteArray(new byte[0]))
+            .build();
+
+        String json = doc.toJson();
+        JsonNode actual = mapper.readTree(json);
+        JsonNode expected = mapper.readTree("{\"empty\":\"\"}");
+        assertThat(expected).isEqualTo(actual);
+    }
+
+    @Test
+    void toJson_listWithAllNulls() throws JsonProcessingException {
+        EnhancedDocument doc = EnhancedDocument.builder()
+            .attributeConverterProviders(defaultProvider())
+            .putJson("nullList", "[null,null,null]")
+            .build();
+
+        String json = doc.toJson();
+        JsonNode actual = mapper.readTree(json);
+        JsonNode expected = mapper.readTree("{\"nullList\":[null,null,null]}");
+        assertThat(expected).isEqualTo(actual);
+    }
+
+    @Test
+    void toJson_mapWithNullValues() throws JsonProcessingException {
+        EnhancedDocument doc = EnhancedDocument.builder()
+            .attributeConverterProviders(defaultProvider())
+            .putJson("nullValues", "{\"key1\":null,\"key2\":\"value\",\"key3\":null}")
+            .build();
+
+        String json = doc.toJson();
+        JsonNode actual = mapper.readTree(json);
+        JsonNode expected = mapper.readTree("{\"nullValues\":{\"key1\":null,\"key2\":\"value\",\"key3\":null}}");
+        assertThat(expected).isEqualTo(actual);
+    }
+
+    @Test
+    void toJson_deeplyNestedStructure() throws JsonProcessingException {
+        String deepJson = "{\"level1\":{\"level2\":{\"level3\":{\"level4\":"
+                          + "{\"level5\":{\"level6\":{\"level7\":{\"value\":\"deep\"}}}}}}}}";
+
+        EnhancedDocument doc = EnhancedDocument.builder()
+            .attributeConverterProviders(defaultProvider())
+            .putJson("nested", deepJson)
+            .build();
+
+        String json = doc.toJson();
+
+        JsonNode actual = mapper.readTree(json);
+        JsonNode expected = mapper.readTree("{\"nested\":" + deepJson + "}");
+        assertThat(expected).isEqualTo(actual);
+    }
+
+    @Test
+    void toJson_deeplyNestedArrays() throws JsonProcessingException {
+        String deepArrayJson = "[[[[[[\"innermost\"]]]]]]";
+
+        EnhancedDocument doc = EnhancedDocument.builder()
+            .attributeConverterProviders(defaultProvider())
+            .putJson("nestedArrays", deepArrayJson)
+            .build();
+
+        String json = doc.toJson();
+        JsonNode actual = mapper.readTree(json);
+        JsonNode expected = mapper.readTree("{\"nestedArrays\":" + deepArrayJson + "}");
+        assertThat(expected).isEqualTo(actual);
+    }
+
+    @Test
+    void toJson_emoji() {
+
+    String emoji = "{\"smile\":\"Hello 😀 World\"}";
+
+    EnhancedDocument doc = EnhancedDocument.builder()
+                                           .attributeConverterProviders(defaultProvider())
+                                           .putJson("emoji", emoji)
+                                           .build();
+
+    String json = doc.toJson();
+    assertThat(json).isEqualTo("{\"emoji\":" + emoji + "}");
+    }
+
+    @Test
+    void getJson_returnsRawValue() {
+        EnhancedDocument doc = EnhancedDocument.builder()
+            .attributeConverterProviders(defaultProvider())
+            .putString("key", "value")
+            .build();
+
+        String result = doc.getJson("key");
+        assertThat(result).isEqualTo("\"value\"");
+    }
+
+    @Test
+    void getJson_nonExistentAttribute() {
+        EnhancedDocument doc = EnhancedDocument.builder()
+            .attributeConverterProviders(defaultProvider())
+            .putString("exists", "value")
+            .build();
+
+        String result = doc.getJson("doesNotExist");
+        assertThat(result).isNull();
+    }
+
 }