Proto文件如何生成JavaProto对象?

首先安装好Protocol Buffer的编译器

Protocol Buffer:
version:2.6.1
link: 链接直达

根据电脑环境进行下载，Widnwos 32/64位就选择win32是没问题的，楼主亲测

1.proto文件编写

Person.proto

public class Person  {
    String name;
    int id;
    String email;
}

syntax = "proto2";
option java_outer_classname="PersonPOJO";
message Person {
	required string name = 1;
	required int32 id = 2;
	required string email = 3;
}

2.生成PersonProto文件

接下来我们要根据上面编写好的Person.proto文件生成Java对应的Proto对象

运行指令

.\protoc.exe --java_out=. Person.proto

如果没有报错就是成功了，有的运行指令会报错

再仔细核对下上面的proto文件即可，这里采用的proto2版本进行生成的，一定要注意版本号的区别，我们下载的版本号就是2.6.1，不同的编译文件可能会有略微差异，但是不影响。

3.PersonPOJO.java

上面的JavaProto文件类名我指定成了PersonPOJO(也就是JavaProto对象)，这里可以看到，里面生成了很多代码，而我们Person实体类属性才只有3个

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

public final class PersonPOJO {
  private PersonPOJO() {}
  public static void registerAllExtensions(
      com.google.protobuf.ExtensionRegistry registry) {
  }
  public interface PersonOrBuilder extends
      // @@protoc_insertion_point(interface_extends:Person)
      com.google.protobuf.MessageOrBuilder {

    /**
     * required string name = 1;
     */
    boolean hasName();
    /**
     * required string name = 1;
     */
    java.lang.String getName();
    /**
     * required string name = 1;
     */
    com.google.protobuf.ByteString
        getNameBytes();

    /**
     * required int32 id = 2;
     */
    boolean hasId();
    /**
     * required int32 id = 2;
     */
    int getId();

    /**
     * required string email = 3;
     */
    boolean hasEmail();
    /**
     * required string email = 3;
     */
    java.lang.String getEmail();
    /**
     * required string email = 3;
     */
    com.google.protobuf.ByteString
        getEmailBytes();
  }
  /**
   * Protobuf type {@code Person}
   */
  public static final class Person extends
      com.google.protobuf.GeneratedMessage implements
      // @@protoc_insertion_point(message_implements:Person)
      PersonOrBuilder {
    // Use Person.newBuilder() to construct.
    private Person(com.google.protobuf.GeneratedMessage.Builder<?> builder) {
      super(builder);
      this.unknownFields = builder.getUnknownFields();
    }
    private Person(boolean noInit) { this.unknownFields = com.google.protobuf.UnknownFieldSet.getDefaultInstance(); }

    private static final Person defaultInstance;
    public static Person getDefaultInstance() {
      return defaultInstance;
    }

    public Person getDefaultInstanceForType() {
      return defaultInstance;
    }

    private final com.google.protobuf.UnknownFieldSet unknownFields;
    @java.lang.Override
    public final com.google.protobuf.UnknownFieldSet
        getUnknownFields() {
      return this.unknownFields;
    }
    private Person(
        com.google.protobuf.CodedInputStream input,
        com.google.protobuf.ExtensionRegistryLite extensionRegistry)
        throws com.google.protobuf.InvalidProtocolBufferException {
      initFields();
      int mutable_bitField0_ = 0;
      com.google.protobuf.UnknownFieldSet.Builder unknownFields =
          com.google.protobuf.UnknownFieldSet.newBuilder();
      try {
        boolean done = false;
        while (!done) {
          int tag = input.readTag();
          switch (tag) {
            case 0:
              done = true;
              break;
            default: {
              if (!parseUnknownField(input, unknownFields,
                                     extensionRegistry, tag)) {
                done = true;
              }
              break;
            }
            case 10: {
              com.google.protobuf.ByteString bs = input.readBytes();
              bitField0_ |= 0x00000001;
              name_ = bs;
              break;
            }
            case 16: {
              bitField0_ |= 0x00000002;
              id_ = input.readInt32();
              break;
            }
            case 26: {
              com.google.protobuf.ByteString bs = input.readBytes();
              bitField0_ |= 0x00000004;
              email_ = bs;
              break;
            }
          }
        }
      } catch (com.google.protobuf.InvalidProtocolBufferException e) {
        throw e.setUnfinishedMessage(this);
      } catch (java.io.IOException e) {
        throw new com.google.protobuf.InvalidProtocolBufferException(
            e.getMessage()).setUnfinishedMessage(this);
      } finally {
        this.unknownFields = unknownFields.build();
        makeExtensionsImmutable();
      }
    }
    public static final com.google.protobuf.Descriptors.Descriptor
        getDescriptor() {
      return PersonPOJO.internal_static_Person_descriptor;
    }

    protected com.google.protobuf.GeneratedMessage.FieldAccessorTable
        internalGetFieldAccessorTable() {
      return PersonPOJO.internal_static_Person_fieldAccessorTable
          .ensureFieldAccessorsInitialized(
              PersonPOJO.Person.class, PersonPOJO.Person.Builder.class);
    }

    public static com.google.protobuf.Parser<Person> PARSER =
        new com.google.protobuf.AbstractParser<Person>() {
      public Person parsePartialFrom(
          com.google.protobuf.CodedInputStream input,
          com.google.protobuf.ExtensionRegistryLite extensionRegistry)
          throws com.google.protobuf.InvalidProtocolBufferException {
        return new Person(input, extensionRegistry);
      }
    };

    @java.lang.Override
    public com.google.protobuf.Parser<Person> getParserForType() {
      return PARSER;
    }

    private int bitField0_;
    public static final int NAME_FIELD_NUMBER = 1;
    private java.lang.Object name_;
    /**
     * required string name = 1;
     */
    public boolean hasName() {
      return ((bitField0_ & 0x00000001) == 0x00000001);
    }
    /**
     * required string name = 1;
     */
    public java.lang.String getName() {
      java.lang.Object ref = name_;
      if (ref instanceof java.lang.String) {
        return (java.lang.String) ref;
      } else {
        com.google.protobuf.ByteString bs = 
            (com.google.protobuf.ByteString) ref;
        java.lang.String s = bs.toStringUtf8();
        if (bs.isValidUtf8()) {
          name_ = s;
        }
        return s;
      }
    }
    /**
     * required string name = 1;
     */
    public com.google.protobuf.ByteString
        getNameBytes() {
      java.lang.Object ref = name_;
      if (ref instanceof java.lang.String) {
        com.google.protobuf.ByteString b = 
            com.google.protobuf.ByteString.copyFromUtf8(
                (java.lang.String) ref);
        name_ = b;
        return b;
      } else {
        return (com.google.protobuf.ByteString) ref;
      }
    }

    public static final int ID_FIELD_NUMBER = 2;
    private int id_;
    /**
     * required int32 id = 2;
     */
    public boolean hasId() {
      return ((bitField0_ & 0x00000002) == 0x00000002);
    }
    /**
     * required int32 id = 2;
     */
    public int getId() {
      return id_;
    }

    public static final int EMAIL_FIELD_NUMBER = 3;
    private java.lang.Object email_;
    /**
     * required string email = 3;
     */
    public boolean hasEmail() {
      return ((bitField0_ & 0x00000004) == 0x00000004);
    }
    /**
     * required string email = 3;
     */
    public java.lang.String getEmail() {
      java.lang.Object ref = email_;
      if (ref instanceof java.lang.String) {
        return (java.lang.String) ref;
      } else {
        com.google.protobuf.ByteString bs = 
            (com.google.protobuf.ByteString) ref;
        java.lang.String s = bs.toStringUtf8();
        if (bs.isValidUtf8()) {
          email_ = s;
        }
        return s;
      }
    }
    /**
     * required string email = 3;
     */
    public com.google.protobuf.ByteString
        getEmailBytes() {
      java.lang.Object ref = email_;
      if (ref instanceof java.lang.String) {
        com.google.protobuf.ByteString b = 
            com.google.protobuf.ByteString.copyFromUtf8(
                (java.lang.String) ref);
        email_ = b;
        return b;
      } else {
        return (com.google.protobuf.ByteString) ref;
      }
    }

    private void initFields() {
      name_ = "";
      id_ = 0;
      email_ = "";
    }
    private byte memoizedIsInitialized = -1;
    public final boolean isInitialized() {
      byte isInitialized = memoizedIsInitialized;
      if (isInitialized == 1) return true;
      if (isInitialized == 0) return false;

      if (!hasName()) {
        memoizedIsInitialized = 0;
        return false;
      }
      if (!hasId()) {
        memoizedIsInitialized = 0;
        return false;
      }
      if (!hasEmail()) {
        memoizedIsInitialized = 0;
        return false;
      }
      memoizedIsInitialized = 1;
      return true;
    }

    public void writeTo(com.google.protobuf.CodedOutputStream output)
                        throws java.io.IOException {
      getSerializedSize();
      if (((bitField0_ & 0x00000001) == 0x00000001)) {
        output.writeBytes(1, getNameBytes());
      }
      if (((bitField0_ & 0x00000002) == 0x00000002)) {
        output.writeInt32(2, id_);
      }
      if (((bitField0_ & 0x00000004) == 0x00000004)) {
        output.writeBytes(3, getEmailBytes());
      }
      getUnknownFields().writeTo(output);
    }

    private int memoizedSerializedSize = -1;
    public int getSerializedSize() {
      int size = memoizedSerializedSize;
      if (size != -1) return size;

      size = 0;
      if (((bitField0_ & 0x00000001) == 0x00000001)) {
        size += com.google.protobuf.CodedOutputStream
          .computeBytesSize(1, getNameBytes());
      }
      if (((bitField0_ & 0x00000002) == 0x00000002)) {
        size += com.google.protobuf.CodedOutputStream
          .computeInt32Size(2, id_);
      }
      if (((bitField0_ & 0x00000004) == 0x00000004)) {
        size += com.google.protobuf.CodedOutputStream
          .computeBytesSize(3, getEmailBytes());
      }
      size += getUnknownFields().getSerializedSize();
      memoizedSerializedSize = size;
      return size;
    }

    private static final long serialVersionUID = 0L;
    @java.lang.Override
    protected java.lang.Object writeReplace()
        throws java.io.ObjectStreamException {
      return super.writeReplace();
    }

    public static PersonPOJO.Person parseFrom(
        com.google.protobuf.ByteString data)
        throws com.google.protobuf.InvalidProtocolBufferException {
      return PARSER.parseFrom(data);
    }
    public static PersonPOJO.Person parseFrom(
        com.google.protobuf.ByteString data,
        com.google.protobuf.ExtensionRegistryLite extensionRegistry)
        throws com.google.protobuf.InvalidProtocolBufferException {
      return PARSER.parseFrom(data, extensionRegistry);
    }
    public static PersonPOJO.Person parseFrom(byte[] data)
        throws com.google.protobuf.InvalidProtocolBufferException {
      return PARSER.parseFrom(data);
    }
    public static PersonPOJO.Person parseFrom(
        byte[] data,
        com.google.protobuf.ExtensionRegistryLite extensionRegistry)
        throws com.google.protobuf.InvalidProtocolBufferException {
      return PARSER.parseFrom(data, extensionRegistry);
    }
    public static PersonPOJO.Person parseFrom(java.io.InputStream input)
        throws java.io.IOException {
      return PARSER.parseFrom(input);
    }
    public static PersonPOJO.Person parseFrom(
        java.io.InputStream input,
        com.google.protobuf.ExtensionRegistryLite extensionRegistry)
        throws java.io.IOException {
      return PARSER.parseFrom(input, extensionRegistry);
    }
    public static PersonPOJO.Person parseDelimitedFrom(java.io.InputStream input)
        throws java.io.IOException {
      return PARSER.parseDelimitedFrom(input);
    }
    public static PersonPOJO.Person parseDelimitedFrom(
        java.io.InputStream input,
        com.google.protobuf.ExtensionRegistryLite extensionRegistry)
        throws java.io.IOException {
      return PARSER.parseDelimitedFrom(input, extensionRegistry);
    }
    public static PersonPOJO.Person parseFrom(
        com.google.protobuf.CodedInputStream input)
        throws java.io.IOException {
      return PARSER.parseFrom(input);
    }
    public static PersonPOJO.Person parseFrom(
        com.google.protobuf.CodedInputStream input,
        com.google.protobuf.ExtensionRegistryLite extensionRegistry)
        throws java.io.IOException {
      return PARSER.parseFrom(input, extensionRegistry);
    }

    public static Builder newBuilder() { return Builder.create(); }
    public Builder newBuilderForType() { return newBuilder(); }
    public static Builder newBuilder(PersonPOJO.Person prototype) {
      return newBuilder().mergeFrom(prototype);
    }
    public Builder toBuilder() { return newBuilder(this); }

    @java.lang.Override
    protected Builder newBuilderForType(
        com.google.protobuf.GeneratedMessage.BuilderParent parent) {
      Builder builder = new Builder(parent);
      return builder;
    }
    /**
     * Protobuf type {@code Person}
     */
    public static final class Builder extends
        com.google.protobuf.GeneratedMessage.Builder<Builder> implements
        // @@protoc_insertion_point(builder_implements:Person)
        PersonPOJO.PersonOrBuilder {
      public static final com.google.protobuf.Descriptors.Descriptor
          getDescriptor() {
        return PersonPOJO.internal_static_Person_descriptor;
      }

      protected com.google.protobuf.GeneratedMessage.FieldAccessorTable
          internalGetFieldAccessorTable() {
        return PersonPOJO.internal_static_Person_fieldAccessorTable
            .ensureFieldAccessorsInitialized(
                PersonPOJO.Person.class, PersonPOJO.Person.Builder.class);
      }

      // Construct using PersonPOJO.Person.newBuilder()
      private Builder() {
        maybeForceBuilderInitialization();
      }

      private Builder(
          com.google.protobuf.GeneratedMessage.BuilderParent parent) {
        super(parent);
        maybeForceBuilderInitialization();
      }
      private void maybeForceBuilderInitialization() {
        if (com.google.protobuf.GeneratedMessage.alwaysUseFieldBuilders) {
        }
      }
      private static Builder create() {
        return new Builder();
      }

      public Builder clear() {
        super.clear();
        name_ = "";
        bitField0_ = (bitField0_ & ~0x00000001);
        id_ = 0;
        bitField0_ = (bitField0_ & ~0x00000002);
        email_ = "";
        bitField0_ = (bitField0_ & ~0x00000004);
        return this;
      }

      public Builder clone() {
        return create().mergeFrom(buildPartial());
      }

      public com.google.protobuf.Descriptors.Descriptor
          getDescriptorForType() {
        return PersonPOJO.internal_static_Person_descriptor;
      }

      public PersonPOJO.Person getDefaultInstanceForType() {
        return PersonPOJO.Person.getDefaultInstance();
      }

      public PersonPOJO.Person build() {
        PersonPOJO.Person result = buildPartial();
        if (!result.isInitialized()) {
          throw newUninitializedMessageException(result);
        }
        return result;
      }

      public PersonPOJO.Person buildPartial() {
        PersonPOJO.Person result = new PersonPOJO.Person(this);
        int from_bitField0_ = bitField0_;
        int to_bitField0_ = 0;
        if (((from_bitField0_ & 0x00000001) == 0x00000001)) {
          to_bitField0_ |= 0x00000001;
        }
        result.name_ = name_;
        if (((from_bitField0_ & 0x00000002) == 0x00000002)) {
          to_bitField0_ |= 0x00000002;
        }
        result.id_ = id_;
        if (((from_bitField0_ & 0x00000004) == 0x00000004)) {
          to_bitField0_ |= 0x00000004;
        }
        result.email_ = email_;
        result.bitField0_ = to_bitField0_;
        onBuilt();
        return result;
      }

      public Builder mergeFrom(com.google.protobuf.Message other) {
        if (other instanceof PersonPOJO.Person) {
          return mergeFrom((PersonPOJO.Person)other);
        } else {
          super.mergeFrom(other);
          return this;
        }
      }

      public Builder mergeFrom(PersonPOJO.Person other) {
        if (other == PersonPOJO.Person.getDefaultInstance()) return this;
        if (other.hasName()) {
          bitField0_ |= 0x00000001;
          name_ = other.name_;
          onChanged();
        }
        if (other.hasId()) {
          setId(other.getId());
        }
        if (other.hasEmail()) {
          bitField0_ |= 0x00000004;
          email_ = other.email_;
          onChanged();
        }
        this.mergeUnknownFields(other.getUnknownFields());
        return this;
      }

      public final boolean isInitialized() {
        if (!hasName()) {
          
          return false;
        }
        if (!hasId()) {
          
          return false;
        }
        if (!hasEmail()) {
          
          return false;
        }
        return true;
      }

      public Builder mergeFrom(
          com.google.protobuf.CodedInputStream input,
          com.google.protobuf.ExtensionRegistryLite extensionRegistry)
          throws java.io.IOException {
        PersonPOJO.Person parsedMessage = null;
        try {
          parsedMessage = PARSER.parsePartialFrom(input, extensionRegistry);
        } catch (com.google.protobuf.InvalidProtocolBufferException e) {
          parsedMessage = (PersonPOJO.Person) e.getUnfinishedMessage();
          throw e;
        } finally {
          if (parsedMessage != null) {
            mergeFrom(parsedMessage);
          }
        }
        return this;
      }
      private int bitField0_;

      private java.lang.Object name_ = "";
      /**
       * required string name = 1;
       */
      public boolean hasName() {
        return ((bitField0_ & 0x00000001) == 0x00000001);
      }
      /**
       * required string name = 1;
       */
      public java.lang.String getName() {
        java.lang.Object ref = name_;
        if (!(ref instanceof java.lang.String)) {
          com.google.protobuf.ByteString bs =
              (com.google.protobuf.ByteString) ref;
          java.lang.String s = bs.toStringUtf8();
          if (bs.isValidUtf8()) {
            name_ = s;
          }
          return s;
        } else {
          return (java.lang.String) ref;
        }
      }
      /**
       * required string name = 1;
       */
      public com.google.protobuf.ByteString
          getNameBytes() {
        java.lang.Object ref = name_;
        if (ref instanceof String) {
          com.google.protobuf.ByteString b = 
              com.google.protobuf.ByteString.copyFromUtf8(
                  (java.lang.String) ref);
          name_ = b;
          return b;
        } else {
          return (com.google.protobuf.ByteString) ref;
        }
      }
      /**
       * required string name = 1;
       */
      public Builder setName(
          java.lang.String value) {
        if (value == null) {
    throw new NullPointerException();
  }
  bitField0_ |= 0x00000001;
        name_ = value;
        onChanged();
        return this;
      }
      /**
       * required string name = 1;
       */
      public Builder clearName() {
        bitField0_ = (bitField0_ & ~0x00000001);
        name_ = getDefaultInstance().getName();
        onChanged();
        return this;
      }
      /**
       * required string name = 1;
       */
      public Builder setNameBytes(
          com.google.protobuf.ByteString value) {
        if (value == null) {
    throw new NullPointerException();
  }
  bitField0_ |= 0x00000001;
        name_ = value;
        onChanged();
        return this;
      }

      private int id_ ;
      /**
       * required int32 id = 2;
       */
      public boolean hasId() {
        return ((bitField0_ & 0x00000002) == 0x00000002);
      }
      /**
       * required int32 id = 2;
       */
      public int getId() {
        return id_;
      }
      /**
       * required int32 id = 2;
       */
      public Builder setId(int value) {
        bitField0_ |= 0x00000002;
        id_ = value;
        onChanged();
        return this;
      }
      /**
       * required int32 id = 2;
       */
      public Builder clearId() {
        bitField0_ = (bitField0_ & ~0x00000002);
        id_ = 0;
        onChanged();
        return this;
      }

      private java.lang.Object email_ = "";
      /**
       * required string email = 3;
       */
      public boolean hasEmail() {
        return ((bitField0_ & 0x00000004) == 0x00000004);
      }
      /**
       * required string email = 3;
       */
      public java.lang.String getEmail() {
        java.lang.Object ref = email_;
        if (!(ref instanceof java.lang.String)) {
          com.google.protobuf.ByteString bs =
              (com.google.protobuf.ByteString) ref;
          java.lang.String s = bs.toStringUtf8();
          if (bs.isValidUtf8()) {
            email_ = s;
          }
          return s;
        } else {
          return (java.lang.String) ref;
        }
      }
      /**
       * required string email = 3;
       */
      public com.google.protobuf.ByteString
          getEmailBytes() {
        java.lang.Object ref = email_;
        if (ref instanceof String) {
          com.google.protobuf.ByteString b = 
              com.google.protobuf.ByteString.copyFromUtf8(
                  (java.lang.String) ref);
          email_ = b;
          return b;
        } else {
          return (com.google.protobuf.ByteString) ref;
        }
      }
      /**
       * required string email = 3;
       */
      public Builder setEmail(
          java.lang.String value) {
        if (value == null) {
    throw new NullPointerException();
  }
  bitField0_ |= 0x00000004;
        email_ = value;
        onChanged();
        return this;
      }
      /**
       * required string email = 3;
       */
      public Builder clearEmail() {
        bitField0_ = (bitField0_ & ~0x00000004);
        email_ = getDefaultInstance().getEmail();
        onChanged();
        return this;
      }
      /**
       * required string email = 3;
       */
      public Builder setEmailBytes(
          com.google.protobuf.ByteString value) {
        if (value == null) {
    throw new NullPointerException();
  }
  bitField0_ |= 0x00000004;
        email_ = value;
        onChanged();
        return this;
      }

      // @@protoc_insertion_point(builder_scope:Person)
    }

    static {
      defaultInstance = new Person(true);
      defaultInstance.initFields();
    }

    // @@protoc_insertion_point(class_scope:Person)
  }

  private static final com.google.protobuf.Descriptors.Descriptor
    internal_static_Person_descriptor;
  private static
    com.google.protobuf.GeneratedMessage.FieldAccessorTable
      internal_static_Person_fieldAccessorTable;

  public static com.google.protobuf.Descriptors.FileDescriptor
      getDescriptor() {
    return descriptor;
  }
  private static com.google.protobuf.Descriptors.FileDescriptor
      descriptor;
  static {
    java.lang.String[] descriptorData = {
      "\n\014Person.proto\"1\n\006Person\022\014\n\004name\030\001 \002(\t\022\n" +
      "\n\002id\030\002 \002(\005\022\r\n\005email\030\003 \002(\tB\014B\nPersonPOJO"
    };
    com.google.protobuf.Descriptors.FileDescriptor.InternalDescriptorAssigner assigner =
        new com.google.protobuf.Descriptors.FileDescriptor.    InternalDescriptorAssigner() {
          public com.google.protobuf.ExtensionRegistry assignDescriptors(
              com.google.protobuf.Descriptors.FileDescriptor root) {
            descriptor = root;
            return null;
          }
        };
    com.google.protobuf.Descriptors.FileDescriptor
      .internalBuildGeneratedFileFrom(descriptorData,
        new com.google.protobuf.Descriptors.FileDescriptor[] {
        }, assigner);
    internal_static_Person_descriptor =
      getDescriptor().getMessageTypes().get(0);
    internal_static_Person_fieldAccessorTable = new
      com.google.protobuf.GeneratedMessage.FieldAccessorTable(
        internal_static_Person_descriptor,
        new java.lang.String[] { "Name", "Id", "Email", });
  }

  // @@protoc_insertion_point(outer_class_scope)
}

4.性能比较

再验证之前pom.xml文件需要导入和我们上面protoc.exe一样的版本号，否则可能会出错，上面的protoc.exe使用的是2.6.1，pom文件也用2.6.1

        <dependency>
            <groupId>com.google.protobufgroupId>
            <artifactId>protobuf-javaartifactId>
            <version>2.6.1version>
        dependency>
        <dependency>
            <groupId>com.alibabagroupId>
            <artifactId>fastjsonartifactId>
            <version>1.2.66version>
        dependency>

这里我们再加上FASTJSON，进行三者之间的对比

package cn.tuling.nettybasic.serializable.protobuf;

import com.alibaba.fastjson.JSON;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectOutputStream;

public class PerformTest {

    public static void main(String[] args) throws IOException {
        long start1 = System.currentTimeMillis();
        PersonOuterClass.Person person = PersonOuterClass.Person.newBuilder()
                .setId(1).setName("Cover").setEmail("[email protected]").build();

        byte[] result = person.toByteArray();
        long end1 = System.currentTimeMillis();
        System.out.println("Proto serialize length:" + result.length + ", time :" + (end1 - start1));
        
        // FAST JSON
        long start3 = System.currentTimeMillis();
        Person person2 = new Person();
        person2.id = 2;
        person2.name = "Cover";
        person2.email = "[email protected]";
        byte[] bytes = JSON.toJSONString(person2).getBytes();
        long end3 = System.currentTimeMillis();
        System.out.println("FASTJSON serialize length: " + bytes.length + ", time :" + (end3 - start3));
        
        // JDK
        long start2 = System.currentTimeMillis();
        Person person1 = new Person();
        person1.id = 2;
        person1.name = "Cover";
        person1.email = "[email protected]";

        ByteArrayOutputStream arrayOutputStream = new ByteArrayOutputStream();
        ObjectOutputStream out = new ObjectOutputStream(arrayOutputStream);
        out.writeObject(person1);
        long end2 = System.currentTimeMillis();
        System.out.println("JDK serialize length:" + arrayOutputStream.toByteArray().length + ", time :" + (end2 - start2));

    }
}

5.序列化结果展示

可以看到，Proto性能在空间复杂度和时间复杂度上总体要比FASTJSON和JDK要有优势，其实还有很多框架序列化和反序列化的性能也不错，下期我们再介绍其他几种框架，Proto的方式相比其他框架要麻烦一点，需要下载特定的编译器才行。它这样做的目的是为了方便地支持跨语言。