1 line fix + benchmark: stop resetting class cache for each document

build.gradle

@@ -71,7 +71,7 @@ java {
 
 ext {
     junitVersion = '5.12.0'
-    jsoniterScalaVersion = '2.33.2'
+    jsoniterScalaVersion = '2.38.9'
 }
 
 dependencies {

src/jmh/java/org/simdjson/SchemaBasedParseBenchmark.java

@@ -0,0 +1,202 @@
+package org.simdjson;
+
+import com.fasterxml.jackson.databind.DeserializationFeature;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.openjdk.jmh.annotations.*;
+import org.openjdk.jmh.infra.Blackhole;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.List;
+import java.util.concurrent.TimeUnit;
+
+@State(Scope.Benchmark)
+@BenchmarkMode(Mode.SingleShotTime)
+@OutputTimeUnit(TimeUnit.MILLISECONDS)
+public class SchemaBasedParseBenchmark {
+    private final SimdJsonParser simdJsonParser = new SimdJsonParser();
+    private final ObjectMapper objectMapper = new ObjectMapper()
+        .configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
+
+    private byte[][] buffers;
+
+    @Setup(Level.Trial)
+    public void setup() throws IOException {
+        try (InputStream is = ParseBenchmark.class.getResourceAsStream("/twitter.json")) {
+            byte[] allBytes = is.readAllBytes();
+            // Reserialize into individual JSON byte arrays to simulate the use case of
+            // deserializing a large number of small (1-2 KB) JSON messages.
+            JsonNode statusesWrapper = objectMapper.readTree(allBytes);
+            JsonNode statusesArray = statusesWrapper.get("statuses");
+
+            buffers = new byte[statusesArray.size()][];
+
+            for (int i = 0; i < statusesArray.size(); i++) {
+                JsonNode status = statusesArray.get(i);
+                byte[] buffer = objectMapper.writeValueAsBytes(status);
+                buffers[i] = buffer;
+            }
+        }
+        System.out.println("VectorSpecies = " + VectorUtils.BYTE_SPECIES);
+        System.out.println("Number of messages = " + buffers.length);
+    }
+
+    @Benchmark
+    public void simdjson(Blackhole blackhole) {
+        for (byte[] buffer : buffers) {
+            blackhole.consume(simdJsonParser.parse(buffer, buffer.length, Status.class));
+        }
+    }
+
+    @Benchmark
+    public void jackson(Blackhole blackhole) throws IOException {
+        for (byte[] buffer : buffers) {
+            blackhole.consume(objectMapper.readValue(buffer, Status.class));
+        }
+    }
+
+    // objects in twitter.json
+    public record Status(
+        Metadata metadata,
+        String created_at,
+        long id,
+        String id_str,
+        String text,
+        String source,
+        boolean truncated,
+        Long in_reply_to_status_id,
+        String in_reply_to_status_id_str,
+        Long in_reply_to_user_id,
+        String in_reply_to_user_id_str,
+        String in_reply_to_screen_name,
+        User user,
+        Object geo,
+        Object coordinates,
+        Object place,
+        Object contributors,
+        // cannot handle recursion
+        // Status retweeted_status,
+        long retweet_count,
+        long favorite_count,
+        Entities entities,
+        boolean favorited,
+        boolean retweeted,
+        Boolean possibly_sensitive,
+        String lang
+    ) {
+        public record Metadata(
+            String result_type,
+            String iso_language_code
+        ) {}
+
+        public record User(
+            long id,
+            String id_str,
+            String name,
+            String screen_name,
+            String location,
+            String description,
+            String url,
+            UserEntities entities,
+            // cannot parse Java keyword
+            // boolean protected,
+            long followers_count,
+            long friends_count,
+            long listed_count,
+            String created_at,
+            long favourites_count,
+            Integer utc_offset,
+            String time_zone,
+            boolean geo_enabled,
+            boolean verified,
+            long statuses_count,
+            String lang,
+            boolean contributors_enabled,
+            boolean is_translator,
+            boolean is_translation_enabled,
+            String profile_background_color,
+            String profile_background_image_url,
+            String profile_background_image_url_https,
+            boolean profile_background_tile,
+            String profile_image_url,
+            String profile_image_url_https,
+            String profile_banner_url,
+            String profile_link_color,
+            String profile_sidebar_border_color,
+            String profile_sidebar_fill_color,
+            String profile_text_color,
+            boolean profile_use_background_image,
+            boolean default_profile,
+            boolean default_profile_image,
+            boolean following,
+            boolean follow_request_sent,
+            boolean notifications
+        ) {}
+
+        public record UserEntities(
+            UrlList url,
+            UrlList description
+        ) {}
+
+        public record Entities(
+            List<Hashtag> hashtags,
+            List<Object> symbols,
+            List<UrlEntity> urls,
+            List<UserMention> user_mentions,
+            List<MediaEntity> media
+        ) {}
+
+        public record UrlList(
+            List<UrlEntity> urls
+        ) {}
+
+        public record Hashtag(
+            String text,
+            List<Integer> indices
+        ) {}
+
+        public record UrlEntity(
+            String url,
+            String expanded_url,
+            String display_url,
+            List<Integer> indices
+        ) {}
+
+        public record UserMention(
+            String screen_name,
+            String name,
+            long id,
+            String id_str,
+            List<Integer> indices
+        ) {}
+
+        public record MediaEntity(
+            long id,
+            String id_str,
+            List<Integer> indices,
+            String media_url,
+            String media_url_https,
+            String url,
+            String display_url,
+            String expanded_url,
+            String type,
+            MediaSizes sizes,
+            Long source_status_id,
+            String source_status_id_str
+        ) {}
+
+        public record MediaSizes(
+            MediaSize medium,
+            MediaSize small,
+            MediaSize thumb,
+            MediaSize large
+        ) {}
+
+        public record MediaSize(
+            int w,
+            int h,
+            String resize
+        ) {}
+    }
+}

src/main/java/org/simdjson/SchemaBasedJsonIterator.java

@@ -28,7 +28,6 @@ class SchemaBasedJsonIterator {
     @SuppressWarnings("unchecked")
     <T> T walkDocument(byte[] padded, int len, Class<T> expectedType) {
         jsonIterator.init(padded, len);
-        classResolver.reset();
 
         ResolvedClass resolvedExpectedClass = classResolver.resolveClass(expectedType);
         return switch (resolvedExpectedClass.getClassCategory()) {