static MemoryBuffer encodeClassDef()

in java/fury-core/src/main/java/org/apache/fury/meta/ClassDefEncoder.java [126:207]
79 lines of code
10 McCabe index (conditional complexity)

  static MemoryBuffer encodeClassDef(
      ClassResolver classResolver,
      Class<?> type,
      Map<String, List<FieldInfo>> classLayers,
      boolean isObjectType) {
    MemoryBuffer classDefBuf = MemoryBuffer.newHeapBuffer(128);
    for (Map.Entry<String, List<FieldInfo>> entry : classLayers.entrySet()) {
      String className = entry.getKey();
      List<FieldInfo> fields = entry.getValue();
      // | num fields + register flag | header + package name | header + class name
      // | header + type id + field name | next field info | ... |
      int currentClassHeader = (fields.size() << 1);
      if (classResolver.isRegisteredById(type)) {
        currentClassHeader |= 1;
        classDefBuf.writeVarUint32Small7(currentClassHeader);
        classDefBuf.writeVarUint32Small7(classResolver.getRegisteredClassId(type));
      } else {
        classDefBuf.writeVarUint32Small7(currentClassHeader);
        Class<?> currentType = getType(type, className);
        String ns, typename;
        if (classResolver.isRegisteredByName(type)) {
          Tuple2<String, String> nameTuple = classResolver.getRegisteredNameTuple(type);
          ns = nameTuple.f0;
          typename = nameTuple.f1;
        } else {
          Tuple2<String, String> encoded = Encoders.encodePkgAndClass(currentType);
          ns = encoded.f0;
          typename = encoded.f1;
        }
        writePkgName(classDefBuf, ns);
        writeTypeName(classDefBuf, typename);
      }
      writeFieldsInfo(classDefBuf, fields);
    }
    byte[] compressed =
        classResolver
            .getFury()
            .getConfig()
            .getMetaCompressor()
            .compress(classDefBuf.getHeapMemory(), 0, classDefBuf.writerIndex());
    boolean isCompressed = false;
    if (compressed.length < classDefBuf.writerIndex()) {
      isCompressed = true;
      classDefBuf = MemoryBuffer.fromByteArray(compressed);
      classDefBuf.writerIndex(compressed.length);
    }
    long hash =
        MurmurHash3.murmurhash3_x64_128(
            classDefBuf.getHeapMemory(), 0, classDefBuf.writerIndex(), 47)[0];
    long header;
    int numClasses = classLayers.size() - 1; // num class must be greater than 0
    if (numClasses > 0b1110) {
      header = 0b1111;
    } else {
      header = numClasses;
    }
    header |= SCHEMA_COMPATIBLE_FLAG;
    if (isObjectType) {
      header |= OBJECT_TYPE_FLAG;
    }
    if (isCompressed) {
      header |= COMPRESSION_FLAG;
    }
    // this id will be part of generated codec, a negative number won't be allowed in class name.
    hash <<= 8;
    header |= Math.abs(hash);
    MemoryBuffer buffer = MemoryUtils.buffer(classDefBuf.writerIndex() + 10);
    int len = classDefBuf.writerIndex() + toInt(numClasses > 0b1110);
    if (len > 255) {
      header |= SIZE_TWO_BYTES_FLAG;
      buffer.writeInt64(header);
      buffer.writeInt16((short) len);
    } else {
      buffer.writeInt64(header);
      buffer.writeByte(len);
    }
    if (numClasses > 0b1110) {
      buffer.writeVarUint32Small7(numClasses - 0b1110);
    }
    buffer.writeBytes(classDefBuf.getHeapMemory(), 0, classDefBuf.writerIndex());
    return buffer;
  }