Add msgpack-jackson3 module for Jackson 3.x support

Adds a new msgpack-jackson3 module providing Jackson 3.x (tools.jackson.*)
integration for MessagePack serialization, requiring Java 17+.

New module structure:
- MessagePackFactory / MessagePackMapper / MessagePackFactoryBuilder
- MessagePackGenerator: deferred-flush design (buffers a node tree, emits
  MessagePack headers with correct sizes on flush/close)
- MessagePackParser: streaming MessagePack deserialization
- MessagePackSerializedString: SerializableString for non-string map keys
- MessagePackExtensionType: extension type support
- TimestampExtensionModule: Instant serialization via msgpack-core timestamps
- JMH benchmarks (src/jmh/java) replacing hand-rolled System.nanoTime tests

Key correctness fixes vs. initial draft:
- Generator contract: streamWriteContext() returns live SimpleStreamWriteContext;
  addValueNode calls writeContext.writeValue(); writeName/writePropertyId check
  writeContext.writeName() return; writeStartArray/Object call _verifyValueWrite
- writePropertyId (integer keys): calls writeContext.writeName() to keep Jackson
  context state in sync alongside the internal node state
- writeString(Reader, int): chunked reading (8192-char buffer) for len>=0 path
  to avoid unbounded upfront allocation
- MessagePackSerializedString: asQuotedUTF8 returns unquoted bytes ("quoted"
  means escaped, not surrounded by quotes); all append/write/put methods
  implemented correctly
- TimestampExtensionModule: IOException wrapped as UncheckedIOException
- MessagePackFactory.snapshot(): delegates to copy() instead of returning this
- isClosed(): fixed by delegating close() lifecycle to super.close()
- ByteBuffer serialization: uses bb.arrayOffset() + bb.position() to honour
  non-zero position
- writeString(char[], offset, len) / writeUTF8String(byte[], offset, len):
  offset bugs fixed
- Stale currentState after container close: reset to IN_ROOT in endCurrentContainer

Build/CI:
- msgpack-jackson3 excluded from root aggregate on Java < 17; CI matrix skips
  the module for older JDK entries
- sbt-jmh plugin added for JMH benchmark support
- OSGi manifest cleaned up; dead code removed

Author: komamitsu

.github/workflows/CI.yml

@@ -28,6 +28,7 @@ jobs:
               - 'project/build.properties'
               - 'msgpack-core/**'
               - 'msgpack-jackson/**'
+              - 'msgpack-jackson3/**'
             docs:
               - '**.md'
               - '**.txt'
@@ -65,6 +66,16 @@ jobs:
           key: ${{ runner.os }}-jdk${{ matrix.java }}-${{ hashFiles('**/*.sbt') }}
           restore-keys: ${{ runner.os }}-jdk${{ matrix.java }}-
       - name: Test
-        run: ./sbt test
+        run: |
+          if [[ ${{ matrix.java }} -lt 17 ]]; then
+            ./sbt msgpack-core/test msgpack-jackson/test
+          else
+            ./sbt test
+          fi
       - name: Universal Buffer Test
-        run: ./sbt test -J-Dmsgpack.universal-buffer=true
+        run: |
+          if [[ ${{ matrix.java }} -lt 17 ]]; then
+            ./sbt msgpack-core/test msgpack-jackson/test -J-Dmsgpack.universal-buffer=true
+          else
+            ./sbt test -J-Dmsgpack.universal-buffer=true
+          fi

build.sbt

@@ -96,10 +96,16 @@ val buildSettings = Seq[Setting[?]](
   Test / compile    := ((Test / compile) dependsOn (Test / jcheckStyle)).value
 )
 
-val junitJupiter = "org.junit.jupiter" % "junit-jupiter"        % "5.14.4" % "test"
-val junitVintage = "org.junit.vintage" % "junit-vintage-engine" % "5.14.4" % "test"
+val junitJupiter   = "org.junit.jupiter" % "junit-jupiter"        % "5.14.4" % "test"
+val junitVintage   = "org.junit.vintage" % "junit-vintage-engine" % "5.14.4" % "test"
+val junitInterface = "com.github.sbt"    % "junit-interface"      % "0.13.3" % "test"
 
 // Project settings
+val isJava17Plus: Boolean = {
+  val v = sys.props.getOrElse("java.specification.version", "1.8")
+  if (v.startsWith("1.")) false else scala.util.Try(v.toInt >= 17).getOrElse(false)
+}
+
 lazy val root = Project(id = "msgpack-java", base = file("."))
   .settings(
     buildSettings,
@@ -108,7 +114,10 @@ lazy val root = Project(id = "msgpack-java", base = file("."))
     publish         := {},
     publishLocal    := {}
   )
-  .aggregate(msgpackCore, msgpackJackson)
+  .aggregate(
+    Seq[ProjectReference](msgpackCore, msgpackJackson) ++
+      (if (isJava17Plus) Seq[ProjectReference](msgpackJackson3) else Nil): _*
+  )
 
 lazy val msgpackCore = Project(id = "msgpack-core", base = file("msgpack-core"))
   .enablePlugins(SbtOsgi)
@@ -170,3 +179,28 @@ lazy val msgpackJackson = Project(id = "msgpack-jackson", base = file("msgpack-j
     testOptions += Tests.Argument(TestFrameworks.JUnit, "-v")
   )
   .dependsOn(msgpackCore)
+
+lazy val msgpackJackson3 = Project(id = "msgpack-jackson3", base = file("msgpack-jackson3"))
+  .enablePlugins(SbtOsgi, JmhPlugin)
+  .settings(
+    buildSettings,
+    name                        := "jackson-dataformat-msgpack3",
+    description                 := "Jackson 3.x extension that adds support for MessagePack",
+    OsgiKeys.bundleSymbolicName := "org.msgpack.msgpack-jackson3",
+    OsgiKeys.exportPackage      := Seq("org.msgpack.jackson", "org.msgpack.jackson.dataformat"),
+    OsgiKeys.importPackage      := Seq("!android.os", "!sun.*"),
+    Test / fork    := true,
+    javacOptions   := Seq("--release", "17"),
+    doc / javacOptions := Seq("--release", "17", "-Xdoclint:none"),
+    libraryDependencies ++=
+      Seq(
+        "tools.jackson.core" % "jackson-databind" % "3.1.2",
+        junitInterface
+      ),
+    testOptions += Tests.Argument(TestFrameworks.JUnit, "-v"),
+    Jmh / javaOptions ++= Seq(
+      "--add-opens=java.base/java.nio=ALL-UNNAMED",
+      "--add-opens=java.base/sun.nio.ch=ALL-UNNAMED"
+    )
+  )
+  .dependsOn(msgpackCore)

msgpack-jackson3/src/jmh/java/org/msgpack/jackson/dataformat/benchmark/BenchmarkState.java

@@ -0,0 +1,32 @@
+package org.msgpack.jackson.dataformat.benchmark;
+
+import org.msgpack.jackson.dataformat.MessagePackFactory;
+import org.msgpack.jackson.dataformat.MessagePackMapper;
+import org.msgpack.jackson.dataformat.benchmark.model.MediaItem;
+import org.msgpack.jackson.dataformat.benchmark.model.MediaItems;
+import org.openjdk.jmh.annotations.Scope;
+import org.openjdk.jmh.annotations.State;
+import tools.jackson.databind.ObjectMapper;
+import tools.jackson.databind.json.JsonMapper;
+
+@State(Scope.Thread)
+public class BenchmarkState
+{
+    public final ObjectMapper msgpackMapper = MessagePackMapper.builder(new MessagePackFactory()).build();
+    public final ObjectMapper jsonMapper = JsonMapper.builder().build();
+
+    public final byte[] msgpackBytes;
+    public final byte[] jsonBytes;
+
+    public BenchmarkState()
+    {
+        try {
+            MediaItem item = MediaItems.stdMediaItem();
+            msgpackBytes = msgpackMapper.writeValueAsBytes(item);
+            jsonBytes = jsonMapper.writeValueAsBytes(item);
+        }
+        catch (Exception e) {
+            throw new RuntimeException(e);
+        }
+    }
+}

msgpack-jackson3/src/jmh/java/org/msgpack/jackson/dataformat/benchmark/MsgpackReadBenchmark.java

@@ -0,0 +1,37 @@
+package org.msgpack.jackson.dataformat.benchmark;
+
+import org.msgpack.jackson.dataformat.benchmark.model.MediaItem;
+import org.openjdk.jmh.annotations.Benchmark;
+import org.openjdk.jmh.annotations.BenchmarkMode;
+import org.openjdk.jmh.annotations.Fork;
+import org.openjdk.jmh.annotations.Measurement;
+import org.openjdk.jmh.annotations.Mode;
+import org.openjdk.jmh.annotations.OutputTimeUnit;
+import org.openjdk.jmh.annotations.Scope;
+import org.openjdk.jmh.annotations.State;
+import org.openjdk.jmh.annotations.Warmup;
+
+import java.util.concurrent.TimeUnit;
+
+@BenchmarkMode(Mode.Throughput)
+@OutputTimeUnit(TimeUnit.SECONDS)
+@State(Scope.Thread)
+@Fork(2)
+@Warmup(iterations = 5, time = 1)
+@Measurement(iterations = 5, time = 1)
+public class MsgpackReadBenchmark
+{
+    private final BenchmarkState state = new BenchmarkState();
+
+    @Benchmark
+    public Object readPojoMsgpack() throws Exception
+    {
+        return state.msgpackMapper.readValue(state.msgpackBytes, MediaItem.class);
+    }
+
+    @Benchmark
+    public Object readPojoJson() throws Exception
+    {
+        return state.jsonMapper.readValue(state.jsonBytes, MediaItem.class);
+    }
+}

msgpack-jackson3/src/jmh/java/org/msgpack/jackson/dataformat/benchmark/MsgpackWriteBenchmark.java

@@ -0,0 +1,43 @@
+package org.msgpack.jackson.dataformat.benchmark;
+
+import org.msgpack.jackson.dataformat.benchmark.model.MediaItem;
+import org.msgpack.jackson.dataformat.benchmark.model.MediaItems;
+import org.openjdk.jmh.annotations.Benchmark;
+import org.openjdk.jmh.annotations.BenchmarkMode;
+import org.openjdk.jmh.annotations.Fork;
+import org.openjdk.jmh.annotations.Measurement;
+import org.openjdk.jmh.annotations.Mode;
+import org.openjdk.jmh.annotations.OutputTimeUnit;
+import org.openjdk.jmh.annotations.Scope;
+import org.openjdk.jmh.annotations.State;
+import org.openjdk.jmh.annotations.Warmup;
+
+import java.util.concurrent.TimeUnit;
+
+@BenchmarkMode(Mode.Throughput)
+@OutputTimeUnit(TimeUnit.SECONDS)
+@State(Scope.Thread)
+@Fork(2)
+@Warmup(iterations = 5, time = 1)
+@Measurement(iterations = 5, time = 1)
+public class MsgpackWriteBenchmark
+{
+    private final BenchmarkState state = new BenchmarkState();
+    private final MediaItem item = MediaItems.stdMediaItem();
+
+    @Benchmark
+    public int writePojoMsgpack() throws Exception
+    {
+        NopOutputStream out = new NopOutputStream();
+        state.msgpackMapper.writeValue(out, item);
+        return out.size();
+    }
+
+    @Benchmark
+    public int writePojoJson() throws Exception
+    {
+        NopOutputStream out = new NopOutputStream();
+        state.jsonMapper.writeValue(out, item);
+        return out.size();
+    }
+}

msgpack-jackson3/src/jmh/java/org/msgpack/jackson/dataformat/benchmark/NopOutputStream.java

@@ -0,0 +1,26 @@
+package org.msgpack.jackson.dataformat.benchmark;
+
+import java.io.OutputStream;
+
+public class NopOutputStream
+        extends OutputStream
+{
+    private int size;
+
+    @Override
+    public void write(int b)
+    {
+        size++;
+    }
+
+    @Override
+    public void write(byte[] b, int off, int len)
+    {
+        size += len;
+    }
+
+    public int size()
+    {
+        return size;
+    }
+}

msgpack-jackson3/src/jmh/java/org/msgpack/jackson/dataformat/benchmark/model/Image.java

@@ -0,0 +1,21 @@
+package org.msgpack.jackson.dataformat.benchmark.model;
+
+public class Image
+{
+    public String uri;
+    public String title;
+    public int width;
+    public int height;
+    public Size size;
+
+    public Image() {}
+
+    public Image(String uri, String title, int width, int height, Size size)
+    {
+        this.uri = uri;
+        this.title = title;
+        this.width = width;
+        this.height = height;
+        this.size = size;
+    }
+}

msgpack-jackson3/src/jmh/java/org/msgpack/jackson/dataformat/benchmark/model/MediaContent.java

@@ -0,0 +1,29 @@
+package org.msgpack.jackson.dataformat.benchmark.model;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class MediaContent
+{
+    public String uri;
+    public String title;
+    public int width;
+    public int height;
+    public String format;
+    public long duration;
+    public long size;
+    public int bitrate;
+    public List<String> persons;
+    public Player player;
+    public String copyright;
+
+    public MediaContent() {}
+
+    public void addPerson(String person)
+    {
+        if (persons == null) {
+            persons = new ArrayList<>();
+        }
+        persons.add(person);
+    }
+}

msgpack-jackson3/src/jmh/java/org/msgpack/jackson/dataformat/benchmark/model/MediaItem.java

@@ -0,0 +1,28 @@
+package org.msgpack.jackson.dataformat.benchmark.model;
+
+import com.fasterxml.jackson.annotation.JsonPropertyOrder;
+
+import java.util.ArrayList;
+import java.util.List;
+
+@JsonPropertyOrder({"content", "images"})
+public class MediaItem
+{
+    public MediaContent content;
+    public List<Image> images;
+
+    public MediaItem() {}
+
+    public MediaItem(MediaContent content)
+    {
+        this.content = content;
+    }
+
+    public void addImage(Image image)
+    {
+        if (images == null) {
+            images = new ArrayList<>();
+        }
+        images.add(image);
+    }
+}

msgpack-jackson3/src/jmh/java/org/msgpack/jackson/dataformat/benchmark/model/MediaItems.java

@@ -0,0 +1,33 @@
+package org.msgpack.jackson.dataformat.benchmark.model;
+
+public class MediaItems
+{
+    private static final MediaItem STD_MEDIA_ITEM;
+
+    static {
+        MediaContent content = new MediaContent();
+        content.uri = "http://javaone.com/keynote.mpg";
+        content.title = "Javaone Keynote";
+        content.width = 640;
+        content.height = 480;
+        content.format = "video/mpg4";
+        content.duration = 18000000L;
+        content.size = 58982400L;
+        content.bitrate = 262144;
+        content.player = Player.JAVA;
+        content.copyright = "None";
+        content.addPerson("Bill Gates");
+        content.addPerson("Steve Jobs");
+
+        MediaItem item = new MediaItem(content);
+        item.addImage(new Image("http://javaone.com/keynote_large.jpg", "Javaone Keynote", 1024, 768, Size.LARGE));
+        item.addImage(new Image("http://javaone.com/keynote_small.jpg", "Javaone Keynote", 320, 240, Size.SMALL));
+
+        STD_MEDIA_ITEM = item;
+    }
+
+    public static MediaItem stdMediaItem()
+    {
+        return STD_MEDIA_ITEM;
+    }
+}