用Maven實現一個protobuf的Java例子

注：試驗環境在Mac Idea環境下

1. 介紹Protocol Buffers

Protocal Buffers(簡稱protobuf)是谷歌的一項技術，用於結構化的數據序列化、反序列化，常用於RPC 系統（Remote Procedure Call Protocol System）和持續數據存儲系統。

其類似於XML生成和解析，但protobuf的效率高於XML，不過protobuf生成的是字節碼，可讀性比XML差，類似的還有json、Java的Serializable等。

很適合做數據存儲或 RPC 數據交換格式。可用於通訊協議、數據存儲等領域的語言無關、平台無關、可擴展的序列化結構數據格式。

2. Idea 安裝protobuf插件

安裝插件protobuf Support，之后重啟

 

3. 配置依賴

pom.xml添加

<dependencies>
        <dependency>
            <groupId>com.google.protobuf</groupId>
            <artifactId>protobuf-java</artifactId>
            <version>3.4.0</version>
        </dependency>
</dependencies>

<build>
        <extensions>
            <extension>
                <groupId>kr.motd.maven</groupId>
                <artifactId>os-maven-plugin</artifactId>
                <version>1.4.1.Final</version>
            </extension>
        </extensions>
        <plugins>
            <plugin>
                <groupId>org.xolstice.maven.plugins</groupId>
                <artifactId>protobuf-maven-plugin</artifactId>
                <version>0.5.0</version>
                <configuration>
                    <protocArtifact>
                        com.google.protobuf:protoc:3.1.0:exe:${os.detected.classifier}
                    </protocArtifact>
                    <pluginId>grpc-java</pluginId>
                </configuration>
                <executions>
                    <execution>
                        <goals>
                            <goal>compile</goal>
                            <goal>compile-custom</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
</build>

4. 書寫proto文件

syntax = "proto3";
option java_package = "com.jihite";
option java_outer_classname = "PersonModel";

message Person {
     int32 id = 1;
     string name = 2;
     string email = 3;
}

 

5. 轉化成Java文件

6. 測試

把生成的類考的代碼路徑下，用下面測試用例測試

package com.jihite;

import com.google.protobuf.InvalidProtocolBufferException;
import org.junit.Test;
public class protobufTest {
    @Test
    public void testN() throws InvalidProtocolBufferException {
        PersonModel.Person.Builder builder = PersonModel.Person.newBuilder();
        builder.setId(1);
        builder.setName("jihite");
        builder.setEmail("[e-mail]");

        PersonModel.Person person = builder.build();
        System.out.println("before:" + person);

        System.out.println("===Person Byte:");
        for (byte b : person.toByteArray()) {
            System.out.print(b);
        }
        System.out.println("================");

        byte[] byteArray = person.toByteArray();
        PersonModel.Person p2 = PersonModel.Person.parseFrom(byteArray);
        System.out.println("after id:" + p2.getId());
        System.out.println("after name:" + p2.getName());
        System.out.println("after email:" + p2.getEmail());

    }
}

 結果

before:id: 1
name: "jihite"
email: "[e-mail]"

===Person Byte:
811861061051041051161012617106105104105116101641061051041051161014699111109================
after id:1
after name:jihite
after email:[e-mail]