android - 将 protobuff 类转换为模型并使用 Realm 存储其值

Question

我正在使用 Squareup Wire protobuf 生成 protobuf 类库

这是我的原型(prototype)文件

syntax = "proto2";

package squareup.dinosaurs;

option java_package = "com.squareup.dinosaurs";


message Dinosaur {
  // Common name of this dinosaur, like "Stegosaurus".
  optional string name = 1;

  // URLs with images of this dinosaur.
  repeated string picture_urls = 2;

}

这是我自动生成的代码

// Code generated by Wire protocol buffer compiler, do not edit.
// Source file: dinosaur/dinosaur.proto at 8:1
package com.squareup.dinosaurs;

import com.squareup.wire.FieldEncoding;
import com.squareup.wire.Message;
import com.squareup.wire.ProtoAdapter;
import com.squareup.wire.ProtoReader;
import com.squareup.wire.ProtoWriter;
import java.io.IOException;
import java.lang.Object;
import java.lang.Override;
import java.lang.String;
import java.lang.StringBuilder;
import java.util.List;
import okio.ByteString;

public final class Dinosaur extends Message<Dinosaur, Dinosaur.Builder> {
  public static final ProtoAdapter<Dinosaur> ADAPTER = new ProtoAdapter<Dinosaur>(FieldEncoding.LENGTH_DELIMITED, Dinosaur.class) {
    @Override
    public int encodedSize(Dinosaur value) {
      return (value.name != null ? ProtoAdapter.STRING.encodedSizeWithTag(1, value.name) : 0)
          + ProtoAdapter.STRING.asRepeated().encodedSizeWithTag(2, value.picture_urls)
          + value.unknownFields().size();
    }

    @Override
    public void encode(ProtoWriter writer, Dinosaur value) throws IOException {
      if (value.name != null) ProtoAdapter.STRING.encodeWithTag(writer, 1, value.name);
      if (value.picture_urls != null) ProtoAdapter.STRING.asRepeated().encodeWithTag(writer, 2, value.picture_urls);
      writer.writeBytes(value.unknownFields());
    }

    @Override
    public Dinosaur decode(ProtoReader reader) throws IOException {
      Builder builder = new Builder();
      long token = reader.beginMessage();
      for (int tag; (tag = reader.nextTag()) != -1;) {
        switch (tag) {
          case 1: builder.name(ProtoAdapter.STRING.decode(reader)); break;
          case 2: builder.picture_urls.add(ProtoAdapter.STRING.decode(reader)); break;
          default: {
            FieldEncoding fieldEncoding = reader.peekFieldEncoding();
            Object value = fieldEncoding.rawProtoAdapter().decode(reader);
            builder.addUnknownField(tag, fieldEncoding, value);
          }
        }
      }
      reader.endMessage(token);
      return builder.build();
    }

    @Override
    public Dinosaur redact(Dinosaur value) {
      Builder builder = value.newBuilder();
      builder.clearUnknownFields();
      return builder.build();
    }
  };

  private static final long serialVersionUID = 0L;

  public static final String DEFAULT_NAME = "";

  /**
   * Common name of this dinosaur, like "Stegosaurus".
   */
  public final String name;

  /**
   * URLs with images of this dinosaur.
   */
  public final List<String> picture_urls;

  public Dinosaur(String name, List<String> picture_urls) {
    this(name, picture_urls, ByteString.EMPTY);
  }

  public Dinosaur(String name, List<String> picture_urls, ByteString unknownFields) {
    super(unknownFields);
    this.name = name;
    this.picture_urls = immutableCopyOf("picture_urls", picture_urls);
  }

  @Override
  public Builder newBuilder() {
    Builder builder = new Builder();
    builder.name = name;
    builder.picture_urls = copyOf("picture_urls", picture_urls);
    builder.addUnknownFields(unknownFields());
    return builder;
  }

  @Override
  public boolean equals(Object other) {
    if (other == this) return true;
    if (!(other instanceof Dinosaur)) return false;
    Dinosaur o = (Dinosaur) other;
    return equals(unknownFields(), o.unknownFields())
        && equals(name, o.name)
        && equals(picture_urls, o.picture_urls);
  }

  @Override
  public int hashCode() {
    int result = super.hashCode;
    if (result == 0) {
      result = unknownFields().hashCode();
      result = result * 37 + (name != null ? name.hashCode() : 0);
      result = result * 37 + (picture_urls != null ? picture_urls.hashCode() : 1);
      super.hashCode = result;
    }
    return result;
  }

  @Override
  public String toString() {
    StringBuilder builder = new StringBuilder();
    if (name != null) builder.append(", name=").append(name);
    if (picture_urls != null) builder.append(", picture_urls=").append(picture_urls);
    return builder.replace(0, 2, "Dinosaur{").append('}').toString();
  }

  public static final class Builder extends com.squareup.wire.Message.Builder<Dinosaur, Builder> {
    public String name;

    public List<String> picture_urls;

    public Builder() {
      picture_urls = newMutableList();
    }

    /**
     * Common name of this dinosaur, like "Stegosaurus".
     */
    public Builder name(String name) {
      this.name = name;
      return this;
    }

    /**
     * URLs with images of this dinosaur.
     */
    public Builder picture_urls(List<String> picture_urls) {
      checkElementsNotNull(picture_urls);
      this.picture_urls = picture_urls;
      return this;
    }

    @Override
    public Dinosaur build() {
      return new Dinosaur(name, picture_urls, buildUnknownFields());
    }
  }
}

现在的问题是我想使用 Realm in android 将 Dinosaur 的值直接存储到数据库中。我想要 Dinosaur 类作为模型。 但问题是 Dinosaur 类被声明为最终类，所以我什至无法派生它。

那么是否存在任何设计模式或方法可以重用Dinosaur类或将其转换为模型？

Answer 1

您不能将 Wire Dinosaur 与 Realm 一起使用，因为 Wire 还要求您扩展 Message 类，而 Realm 则要求您扩展 RealmObject .

如果您想将两者结合起来，您可以创建一个接受电线 Dinosaur 的 RealmDinosaur 类。像这样的事情:

public class RealmDinosaur extends RealmObject {

  private String name;
  private RealmList<RealmString> pictureUrls;

  public RealmDinosaur(Dinosaur dino) {
    // Fill Realm fields. Note that Realm doesn't support Lists 
    // with primitive strings yet.
    // See https://realm.io/docs/java/latest/#primitive-lists
  }

  // getter and setters

}

realm.beginTransaction();
realm.copyToRealm(new RealmDinosaur(wireDinosaur));
realm.commitTransaction();