protobuf-Java使用.md

protobuf 环境配置

1、安装编译器

下载地址

直接解压缩。

2、配置环境变量

环境变量Path 中增加安装目录的路径

3、检查是否配置成功

protoc
Usage: protoc [OPTION] PROTO_FILES
Parse PROTO_FILES and generate output based on the options given:
  -IPATH, --proto_path=PATH   Specify the directory in which to search for
                              imports.  May be specified multiple times;
                              directories will be searched in order.  If not
                              given, the current working directory is used.
                              If not found in any of the these directories,
                              the --descriptor_set_in descriptors will be
                              checked for required proto file.
  --version                   #版本
  -h, --help                  #帮助
  --encode=MESSAGE_TYPE       Read a text-format message of the given type
                              from standard input and write it in binary
                              to standard output.  The message type must
                              be defined in PROTO_FILES or their imports.
  --deterministic_output      When using --encode, ensure map fields are
                              deterministically ordered. Note that this order
                              is not canonical, and changes across builds or
                              releases of protoc.
  --decode=MESSAGE_TYPE       Read a binary message of the given type from
                              standard input and write it in text format
                              to standard output.  The message type must
                              be defined in PROTO_FILES or their imports.
  --decode_raw                Read an arbitrary protocol message from
                              standard input and write the raw tag/value
                              pairs in text format to standard output.  No
                              PROTO_FILES should be given when using this
                              flag.
  --descriptor_set_in=FILES   Specifies a delimited list of FILES
                              each containing a FileDescriptorSet (a
                              protocol buffer defined in descriptor.proto).
                              The FileDescriptor for each of the PROTO_FILES
                              provided will be loaded from these
                              FileDescriptorSets. If a FileDescriptor
                              appears multiple times, the first occurrence
                              will be used.
  -oFILE,                     Writes a FileDescriptorSet (a protocol buffer,
    --descriptor_set_out=FILE defined in descriptor.proto) containing all of
                              the input files to FILE.
  --include_imports           When using --descriptor_set_out, also include
                              all dependencies of the input files in the
                              set, so that the set is self-contained.
  --include_source_info       When using --descriptor_set_out, do not strip
                              SourceCodeInfo from the FileDescriptorProto.
                              This results in vastly larger descriptors that
                              include information about the original
                              location of each decl in the source file as
                              well as surrounding comments.
  --retain_options            When using --descriptor_set_out, do not strip
                              any options from the FileDescriptorProto.
                              This results in potentially larger descriptors
                              that include information about options that were
                              only meant to be useful during compilation.
  --dependency_out=FILE       Write a dependency output file in the format
                              expected by make. This writes the transitive
                              set of input file paths to FILE
  --error_format=FORMAT       Set the format in which to print errors.
                              FORMAT may be 'gcc' (the default) or 'msvs'
                              (Microsoft Visual Studio format).
  --fatal_warnings            Make warnings be fatal (similar to -Werr in
                              gcc). This flag will make protoc return
                              with a non-zero exit code if any warnings
                              are generated.
  --print_free_field_numbers  Print the free field numbers of the messages
                              defined in the given proto files. Extension ranges
                              are counted as occupied fields numbers.
  --enable_codegen_trace      Enables tracing which parts of protoc are
                              responsible for what codegen output. Not supported
                              by all backends or on all platforms.
  --plugin=EXECUTABLE         Specifies a plugin executable to use.
                              Normally, protoc searches the PATH for
                              plugins, but you may specify additional
                              executables not in the path using this flag.
                              Additionally, EXECUTABLE may be of the form
                              NAME=PATH, in which case the given plugin name
                              is mapped to the given executable even if
                              the executable's own name differs.
  --cpp_out=OUT_DIR           Generate C++ header and source.
  --csharp_out=OUT_DIR        Generate C# source file.
  --java_out=OUT_DIR          Generate Java source file.
  --kotlin_out=OUT_DIR        Generate Kotlin file.
  --objc_out=OUT_DIR          Generate Objective-C header and source.
  --php_out=OUT_DIR           Generate PHP source file.
  --pyi_out=OUT_DIR           Generate python pyi stub.
  --python_out=OUT_DIR        Generate Python source file.
  --ruby_out=OUT_DIR          Generate Ruby source file.
  --rust_out=OUT_DIR          Generate Rust sources.
  @<filename>                 Read options and filenames from file. If a
                              relative file path is specified, the file
                              will be searched in the working directory.
                              The --proto_path option will not affect how
                              this argument file is searched. Content of
                              the file will be expanded in the position of
                              @<filename> as in the argument list. Note
                              that shell expansion is not applied to the
                              content of the file (i.e., you cannot use
                              quotes, wildcards, escapes, commands, etc.).
                              Each line corresponds to a single argument,
                              even if it contains spaces.

E:\setups\protoc-25.0-win64\bin\protoc.exe --java_out=E:\projects_study\research\base\target Data2.proto 

idea 中使用 protobuf

1、idea 安装 protobuf 相关插件

安装插件：

• protobuf generator：根据 .proto 文件来生成 proto 对象
• pojo to proto：类文件-右键-PojoProto, 将简单Java类型转成proto message拷贝至剪贴板

2、配置全局 protobuf

人工生成Java文件

1、引入包

        <!--  protobuf 支持 Java 核心包-->
        <dependency>
            <groupId>com.google.protobuf</groupId>
            <artifactId>protobuf-java</artifactId>
            <version>3.21.11</version>
        </dependency>

      <!--  proto 与 Json 互转会用到-->
        <dependency>
            <groupId>com.google.protobuf</groupId>
            <artifactId>protobuf-java-util</artifactId>
            <version>3.15.3</version>
        </dependency>

2、编写.proto文件

//使用 proto3 语法 ,未指定则使用proto2
syntax = "proto3";

//生成 proto 文件所在包路径
package demon.research.proto;

//生成的 proto 文件所在包路径
option java_package = "demon.research.proto";

//生成的 proto 文件名
option java_outer_classname="DataGen";

//message关键字 定义一个消息体。
message DataOriginal{
  int32 id = 1;
  string code = 2;
  string name = 3;
}

3、生成Java 文件

直接在文件上点击右键，quick gen protobuf here，则在此目录根据包生成一个java文件，名字为Data.java.

quick gen protobuf rules 则根据配置的规则，把java文件生成在指定的目录。

然后把生成的Java文件，copy到java类目录下。

4、序列化和反序列化

        //初始化数据
        DataGen.DataOriginal.Builder builder = DataGen.DataOriginal.newBuilder();

        builder.setId(1).setCode("001").setName("张三").build();

        //序列化
        DataGen.DataOriginal build = builder.build();
        //转换成字节数组
        byte[] s = build.toByteArray();
        System.out.println("protobuf数据bytes[]:" + Arrays.toString(s));
        System.out.println("protobuf序列化大小: " + s.length);

        DataGen.DataOriginal data = null;
        String jsonObject = null;
        try {
            //反序列化
            data = DataGen.DataOriginal.parseFrom(s);
            //转 json
            jsonObject = JsonFormat.printer().print(data);
        } catch (Exception e) {
            e.printStackTrace();
        }

        System.out.println("Json格式化结果:\n" + jsonObject);
        System.out.println("Json格式化数据大小: " + jsonObject.getBytes().length);

输出结果：

protobuf数据bytes[]:[8, 1, 18, 3, 48, 48, 49, 26, 6, -27, -68, -96, -28, -72, -119]
protobuf序列化大小: 15
Json格式化结果:
{
  "id": 1,
  "code": "001",
  "name": "张三"
}
Json格式化数据大小: 50

传输的数据，确实比json格式的要小。

maven自动生成

引入插件

        <extensions>
            <extension>
                <groupId>kr.motd.maven</groupId>
                <artifactId>os-maven-plugin</artifactId>
                <version>1.5.0.Final</version>
            </extension>
        </extensions>
        
        <plugin>
                <groupId>org.xolstice.maven.plugins</groupId>
                <artifactId>protobuf-maven-plugin</artifactId>
                <version>0.6.1</version>
                <configuration>
                    <protocArtifact>com.google.protobuf:protoc:3.21.11:exe:${os.detected.classifier}
                    </protocArtifact>
                    <pluginId>grpc-java</pluginId>
                    <pluginArtifact>io.grpc:protoc-gen-grpc-java:3.21.11:exe:${os.detected.classifier}
                    </pluginArtifact>
                </configuration>
                <executions>
                    <execution>
                        <goals>
                            <goal>compile</goal>
                            <goal>compile-custom</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>

默认.proto文件的扫描目录为： ${basedir}/src/main/proto

默认生成的文件路径为：${project.build.directory}/generated-sources/protobuf/java.

需要人工把代码放到指定目录。如果需要自动生成到指定目录，则修改指定目录。

注意：默认会把指定的目录数据都给删除掉。，可以设置clearOutputDirectory为false。

附录

参考

下载地址

生成代码

// Generated by the protocol buffer compiler.  DO NOT EDIT!
// source: DataOriginal.proto

// Protobuf Java Version: 3.25.0

// java_package  设置的包名
package demon.research.proto;

//java_outer_classname 指定的类名
public final class DataGen {
    //避免修改
  private DataGen() {}
  public static void registerAllExtensions(
      com.google.protobuf.ExtensionRegistryLite registry) {
  }

  public static void registerAllExtensions(
      com.google.protobuf.ExtensionRegistry registry) {
    registerAllExtensions(
        (com.google.protobuf.ExtensionRegistryLite) registry);
  }
    
    //构造器模式。
  public interface DataOriginalOrBuilder extends
      // @@protoc_insertion_point(interface_extends:demon.research.proto.DataOriginal)
      com.google.protobuf.MessageOrBuilder {

    /**
     * <code>int32 id = 1;</code>
     * @return The id.
     */
    int getId();

     
     //******************* 会为字符串类型 生成序列化 方法。
    /**
     * <code>string code = 2;</code>
     * @return The code.
     */
    String getCode();
    /**
     * <code>string code = 2;</code>
     * @return The bytes for code.
     */
    com.google.protobuf.ByteString
        getCodeBytes();

    /**
     * <code>string name = 3;</code>
     * @return The name.
     */
    String getName();
    /**
     * <code>string name = 3;</code>
     * @return The bytes for name.
     */
    com.google.protobuf.ByteString
        getNameBytes();
  }
  /**
   * <pre>
   *message关键字 定义一个消息体。
   * </pre>
   *
   * Protobuf type {@code demon.research.proto.DataOriginal}
   */
  public static final class DataOriginal extends
      com.google.protobuf.GeneratedMessageV3 implements
      // @@protoc_insertion_point(message_implements:demon.research.proto.DataOriginal)
      DataOriginalOrBuilder {
  private static final long serialVersionUID = 0L;
    // Use DataOriginal.newBuilder() to construct.
    private DataOriginal(com.google.protobuf.GeneratedMessageV3.Builder<?> builder) {
      super(builder);
    }
    private DataOriginal() {
      code_ = "";
      name_ = "";
    }

    @Override
    @SuppressWarnings({"unused"})
    protected Object newInstance(
        UnusedPrivateParameter unused) {
      return new DataOriginal();
    }

    public static final com.google.protobuf.Descriptors.Descriptor
        getDescriptor() {
      return DataGen.internal_static_demon_research_proto_DataOriginal_descriptor;
    }

    @Override
    protected FieldAccessorTable
        internalGetFieldAccessorTable() {
      return DataGen.internal_static_demon_research_proto_DataOriginal_fieldAccessorTable
          .ensureFieldAccessorsInitialized(
              DataOriginal.class, Builder.class);
    }

    public static final int ID_FIELD_NUMBER = 1;
    private int id_ = 0;
    /**
     * <code>int32 id = 1;</code>
     * @return The id.
     */
    @Override
    public int getId() {
      return id_;
    }

    public static final int CODE_FIELD_NUMBER = 2;
    @SuppressWarnings("serial")
    private volatile Object code_ = "";
    /**
     * <code>string code = 2;</code>
     * @return The code.
     */
    @Override
    public String getCode() {
      Object ref = code_;
      if (ref instanceof String) {
        return (String) ref;
      } else {
        com.google.protobuf.ByteString bs = 
            (com.google.protobuf.ByteString) ref;
        String s = bs.toStringUtf8();
        code_ = s;
        return s;
      }
    }
    /**
     * <code>string code = 2;</code>
     * @return The bytes for code.
     */
    @Override
    public com.google.protobuf.ByteString
        getCodeBytes() {
      Object ref = code_;
      if (ref instanceof String) {
        com.google.protobuf.ByteString b = 
            com.google.protobuf.ByteString.copyFromUtf8(
                (String) ref);
        code_ = b;
        return b;
      } else {
        return (com.google.protobuf.ByteString) ref;
      }
    }

    public static final int NAME_FIELD_NUMBER = 3;
    @SuppressWarnings("serial")
    private volatile Object name_ = "";
    /**
     * <code>string name = 3;</code>
     * @return The name.
     */
    @Override
    public String getName() {
      Object ref = name_;
      if (ref instanceof String) {
        return (String) ref;
      } else {
        com.google.protobuf.ByteString bs = 
            (com.google.protobuf.ByteString) ref;
        String s = bs.toStringUtf8();
        name_ = s;
        return s;
      }
    }
    /**
     * <code>string name = 3;</code>
     * @return The bytes for name.
     */
    @Override
    public com.google.protobuf.ByteString
        getNameBytes() {
      Object ref = name_;
      if (ref instanceof String) {
        com.google.protobuf.ByteString b = 
            com.google.protobuf.ByteString.copyFromUtf8(
                (String) ref);
        name_ = b;
        return b;
      } else {
        return (com.google.protobuf.ByteString) ref;
      }
    }

    private byte memoizedIsInitialized = -1;
    @Override
    public final boolean isInitialized() {
      byte isInitialized = memoizedIsInitialized;
      if (isInitialized == 1) return true;
      if (isInitialized == 0) return false;

      memoizedIsInitialized = 1;
      return true;
    }

    @Override
    public void writeTo(com.google.protobuf.CodedOutputStream output)
                        throws java.io.IOException {
      if (id_ != 0) {
        output.writeInt32(1, id_);
      }
      if (!com.google.protobuf.GeneratedMessageV3.isStringEmpty(code_)) {
        com.google.protobuf.GeneratedMessageV3.writeString(output, 2, code_);
      }
      if (!com.google.protobuf.GeneratedMessageV3.isStringEmpty(name_)) {
        com.google.protobuf.GeneratedMessageV3.writeString(output, 3, name_);
      }
      getUnknownFields().writeTo(output);
    }

    @Override
    public int getSerializedSize() {
      int size = memoizedSize;
      if (size != -1) return size;

      size = 0;
      if (id_ != 0) {
        size += com.google.protobuf.CodedOutputStream
          .computeInt32Size(1, id_);
      }
      if (!com.google.protobuf.GeneratedMessageV3.isStringEmpty(code_)) {
        size += com.google.protobuf.GeneratedMessageV3.computeStringSize(2, code_);
      }
      if (!com.google.protobuf.GeneratedMessageV3.isStringEmpty(name_)) {
        size += com.google.protobuf.GeneratedMessageV3.computeStringSize(3, name_);
      }
      size += getUnknownFields().getSerializedSize();
      memoizedSize = size;
      return size;
    }

    @Override
    public boolean equals(final Object obj) {
      if (obj == this) {
       return true;
      }
      if (!(obj instanceof DataOriginal)) {
        return super.equals(obj);
      }
      DataOriginal other = (DataOriginal) obj;

      if (getId()
          != other.getId()) return false;
      if (!getCode()
          .equals(other.getCode())) return false;
      if (!getName()
          .equals(other.getName())) return false;
      if (!getUnknownFields().equals(other.getUnknownFields())) return false;
      return true;
    }

    @Override
    public int hashCode() {
      if (memoizedHashCode != 0) {
        return memoizedHashCode;
      }
      int hash = 41;
      hash = (19 * hash) + getDescriptor().hashCode();
      hash = (37 * hash) + ID_FIELD_NUMBER;
      hash = (53 * hash) + getId();
      hash = (37 * hash) + CODE_FIELD_NUMBER;
      hash = (53 * hash) + getCode().hashCode();
      hash = (37 * hash) + NAME_FIELD_NUMBER;
      hash = (53 * hash) + getName().hashCode();
      hash = (29 * hash) + getUnknownFields().hashCode();
      memoizedHashCode = hash;
      return hash;
    }

    public static DataOriginal parseFrom(
        java.nio.ByteBuffer data)
        throws com.google.protobuf.InvalidProtocolBufferException {
      return PARSER.parseFrom(data);
    }
    public static DataOriginal parseFrom(
        java.nio.ByteBuffer data,
        com.google.protobuf.ExtensionRegistryLite extensionRegistry)
        throws com.google.protobuf.InvalidProtocolBufferException {
      return PARSER.parseFrom(data, extensionRegistry);
    }
    public static DataOriginal parseFrom(
        com.google.protobuf.ByteString data)
        throws com.google.protobuf.InvalidProtocolBufferException {
      return PARSER.parseFrom(data);
    }
    public static DataOriginal parseFrom(
        com.google.protobuf.ByteString data,
        com.google.protobuf.ExtensionRegistryLite extensionRegistry)
        throws com.google.protobuf.InvalidProtocolBufferException {
      return PARSER.parseFrom(data, extensionRegistry);
    }
    public static DataOriginal parseFrom(byte[] data)
        throws com.google.protobuf.InvalidProtocolBufferException {
      return PARSER.parseFrom(data);
    }
    public static DataOriginal parseFrom(
        byte[] data,
        com.google.protobuf.ExtensionRegistryLite extensionRegistry)
        throws com.google.protobuf.InvalidProtocolBufferException {
      return PARSER.parseFrom(data, extensionRegistry);
    }
    public static DataOriginal parseFrom(java.io.InputStream input)
        throws java.io.IOException {
      return com.google.protobuf.GeneratedMessageV3
          .parseWithIOException(PARSER, input);
    }
    public static DataOriginal parseFrom(
        java.io.InputStream input,
        com.google.protobuf.ExtensionRegistryLite extensionRegistry)
        throws java.io.IOException {
      return com.google.protobuf.GeneratedMessageV3
          .parseWithIOException(PARSER, input, extensionRegistry);
    }

    public static DataOriginal parseDelimitedFrom(java.io.InputStream input)
        throws java.io.IOException {
      return com.google.protobuf.GeneratedMessageV3
          .parseDelimitedWithIOException(PARSER, input);
    }

    public static DataOriginal parseDelimitedFrom(
        java.io.InputStream input,
        com.google.protobuf.ExtensionRegistryLite extensionRegistry)
        throws java.io.IOException {
      return com.google.protobuf.GeneratedMessageV3
          .parseDelimitedWithIOException(PARSER, input, extensionRegistry);
    }
    public static DataOriginal parseFrom(
        com.google.protobuf.CodedInputStream input)
        throws java.io.IOException {
      return com.google.protobuf.GeneratedMessageV3
          .parseWithIOException(PARSER, input);
    }
    public static DataOriginal parseFrom(
        com.google.protobuf.CodedInputStream input,
        com.google.protobuf.ExtensionRegistryLite extensionRegistry)
        throws java.io.IOException {
      return com.google.protobuf.GeneratedMessageV3
          .parseWithIOException(PARSER, input, extensionRegistry);
    }

    @Override
    public Builder newBuilderForType() { return newBuilder(); }
    public static Builder newBuilder() {
      return DEFAULT_INSTANCE.toBuilder();
    }
    public static Builder newBuilder(DataOriginal prototype) {
      return DEFAULT_INSTANCE.toBuilder().mergeFrom(prototype);
    }
    @Override
    public Builder toBuilder() {
      return this == DEFAULT_INSTANCE
          ? new Builder() : new Builder().mergeFrom(this);
    }

    @Override
    protected Builder newBuilderForType(
        BuilderParent parent) {
      Builder builder = new Builder(parent);
      return builder;
    }
    /**
     * <pre>
     *message关键字 定义一个消息体。
     * </pre>
     *
     * Protobuf type {@code demon.research.proto.DataOriginal}
     */
    public static final class Builder extends
        com.google.protobuf.GeneratedMessageV3.Builder<Builder> implements
        // @@protoc_insertion_point(builder_implements:demon.research.proto.DataOriginal)
        DataOriginalOrBuilder {
      public static final com.google.protobuf.Descriptors.Descriptor
          getDescriptor() {
        return DataGen.internal_static_demon_research_proto_DataOriginal_descriptor;
      }

      @Override
      protected FieldAccessorTable
          internalGetFieldAccessorTable() {
        return DataGen.internal_static_demon_research_proto_DataOriginal_fieldAccessorTable
            .ensureFieldAccessorsInitialized(
                DataOriginal.class, Builder.class);
      }

      // Construct using demon.research.proto.DataGen.DataOriginal.newBuilder()
      private Builder() {

      }

      private Builder(
          BuilderParent parent) {
        super(parent);

      }
      @Override
      public Builder clear() {
        super.clear();
        bitField0_ = 0;
        id_ = 0;
        code_ = "";
        name_ = "";
        return this;
      }

      @Override
      public com.google.protobuf.Descriptors.Descriptor
          getDescriptorForType() {
        return DataGen.internal_static_demon_research_proto_DataOriginal_descriptor;
      }

      @Override
      public DataOriginal getDefaultInstanceForType() {
        return DataOriginal.getDefaultInstance();
      }

      @Override
      public DataOriginal build() {
        DataOriginal result = buildPartial();
        if (!result.isInitialized()) {
          throw newUninitializedMessageException(result);
        }
        return result;
      }

      @Override
      public DataOriginal buildPartial() {
        DataOriginal result = new DataOriginal(this);
        if (bitField0_ != 0) { buildPartial0(result); }
        onBuilt();
        return result;
      }

      private void buildPartial0(DataOriginal result) {
        int from_bitField0_ = bitField0_;
        if (((from_bitField0_ & 0x00000001) != 0)) {
          result.id_ = id_;
        }
        if (((from_bitField0_ & 0x00000002) != 0)) {
          result.code_ = code_;
        }
        if (((from_bitField0_ & 0x00000004) != 0)) {
          result.name_ = name_;
        }
      }

      @Override
      public Builder clone() {
        return super.clone();
      }
      @Override
      public Builder setField(
          com.google.protobuf.Descriptors.FieldDescriptor field,
          Object value) {
        return super.setField(field, value);
      }
      @Override
      public Builder clearField(
          com.google.protobuf.Descriptors.FieldDescriptor field) {
        return super.clearField(field);
      }
      @Override
      public Builder clearOneof(
          com.google.protobuf.Descriptors.OneofDescriptor oneof) {
        return super.clearOneof(oneof);
      }
      @Override
      public Builder setRepeatedField(
          com.google.protobuf.Descriptors.FieldDescriptor field,
          int index, Object value) {
        return super.setRepeatedField(field, index, value);
      }
      @Override
      public Builder addRepeatedField(
          com.google.protobuf.Descriptors.FieldDescriptor field,
          Object value) {
        return super.addRepeatedField(field, value);
      }
      @Override
      public Builder mergeFrom(com.google.protobuf.Message other) {
        if (other instanceof DataOriginal) {
          return mergeFrom((DataOriginal)other);
        } else {
          super.mergeFrom(other);
          return this;
        }
      }

      public Builder mergeFrom(DataOriginal other) {
        if (other == DataOriginal.getDefaultInstance()) return this;
        if (other.getId() != 0) {
          setId(other.getId());
        }
        if (!other.getCode().isEmpty()) {
          code_ = other.code_;
          bitField0_ |= 0x00000002;
          onChanged();
        }
        if (!other.getName().isEmpty()) {
          name_ = other.name_;
          bitField0_ |= 0x00000004;
          onChanged();
        }
        this.mergeUnknownFields(other.getUnknownFields());
        onChanged();
        return this;
      }

      @Override
      public final boolean isInitialized() {
        return true;
      }

      @Override
      public Builder mergeFrom(
          com.google.protobuf.CodedInputStream input,
          com.google.protobuf.ExtensionRegistryLite extensionRegistry)
          throws java.io.IOException {
        if (extensionRegistry == null) {
          throw new NullPointerException();
        }
        try {
          boolean done = false;
          while (!done) {
            int tag = input.readTag();
            switch (tag) {
              case 0:
                done = true;
                break;
              case 8: {
                id_ = input.readInt32();
                bitField0_ |= 0x00000001;
                break;
              } // case 8
              case 18: {
                code_ = input.readStringRequireUtf8();
                bitField0_ |= 0x00000002;
                break;
              } // case 18
              case 26: {
                name_ = input.readStringRequireUtf8();
                bitField0_ |= 0x00000004;
                break;
              } // case 26
              default: {
                if (!super.parseUnknownField(input, extensionRegistry, tag)) {
                  done = true; // was an endgroup tag
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                break;
              } // default:
            } // switch (tag)
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1、DataGen 类只提供框架方法。

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int getId();
String getCode();
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String getName();
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3、类DataOriginal 继承类 com.google.protobuf.GeneratedMessageV3 ，实现接口 DataOriginalOrBuilder提供了get方法，并保存了数据。同时提供了序列化与反序列化能力

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4、类Builder 继承类 com.google.protobuf.GeneratedMessageV3.Builder<Builder> ，实现接口 DataOriginalOrBuilder提供了get/set方法，