android - protobuf lite和protobuf java中的重复类

Question

我在android实现中使用带有protobuf lite的grpc。但是 protobuf lite 没有 google 时间戳，我的 protos 已经导入“google/protobuf/timestamp.proto”。所以我将实现 'com.google.protobuf:protobuf-java:3.7.1' 添加到包含谷歌时间戳的 gradle 中。但在那之后代码编译有错误。例如:在模块 protobuf-java-3.7.1.jar (com.google.protobuf:protobuf-java:3.7.1) 和 protobuf-lite-3.0.1.jar ( com.google.protobuf:protobuf-lite:3.0.1)。
任何解决此问题的想法将不胜感激。

apply plugin: 'com.android.application'
apply plugin: 'com.google.protobuf'

android {
    compileSdkVersion 28
    buildToolsVersion "29.0.0"
    defaultConfig {
        minSdkVersion 21
        targetSdkVersion 28
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        debug {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }

    sourceSets {
        main {
            proto {
                srcDir 'src/main'
            }
            java {
                srcDir 'src/main'
            }
        }
    }
}

protobuf {
    protoc { artifact = 'com.google.protobuf:protoc:3.7.1' }
    plugins {
        javalite { artifact = "com.google.protobuf:protoc-gen-javalite:3.0.0" }
        grpc {
            artifact = 'io.grpc:protoc-gen-grpc-java:1.20.0' // CURRENT_GRPC_VERSION
        }
    }

    generateProtoTasks {
        all().each { task ->
            task.plugins {
                javalite {}
                grpc { // Options added to --grpc_out
                    option 'lite'
                }
            }
        }
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'androidx.appcompat:appcompat:1.0.2'
    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
    implementation 'androidx.legacy:legacy-support-v4:1.0.0'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test:runner:1.2.0'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
    implementation 'com.google.android.material:material:1.0.0'

    // You need to build grpc-java to obtain these libraries below.
    implementation 'io.grpc:grpc-okhttp:1.20.0'
    implementation 'io.grpc:grpc-protobuf-lite:1.22.1'
    implementation 'io.grpc:grpc-stub:1.20.0'
    implementation 'javax.annotation:javax.annotation-api:1.3.2'
    implementation 'com.google.protobuf:protobuf-java:3.7.1'
}

给定的错误是:

Duplicate class com.google.protobuf.AbstractMessageLite found in modules      protobuf-java-3.7.1.jar (com.google.protobuf:protobuf-java:3.7.1) and protobuf-lite-3.0.1.jar (com.google.protobuf:protobuf-lite:3.0.1)
Duplicate class com.google.protobuf.AbstractMessageLite$Builder found in modules protobuf-java-3.7.1.jar (com.google.protobuf:protobuf-java:3.7.1) and protobuf-lite-3.0.1.jar (com.google.protobuf:protobuf-lite:3.0.1)
Duplicate class com.google.protobuf.AbstractMessageLite$Builder$LimitedInputStream found in modules protobuf-java-3.7.1.jar (com.google.protobuf:protobuf-java:3.7.1) and protobuf-lite-3.0.1.jar (com.google.protobuf:protobuf-lite:3.0.1)
Duplicate class com.google.protobuf.AbstractParser found in modules protobuf-java-3.7.1.jar (com.google.protobuf:protobuf-java:3.7.1) and protobuf-lite-3.0.1.jar (com.google.protobuf:protobuf-lite:3.0.1)
Duplicate class com.google.protobuf.AbstractProtobufList found in modules protobuf-java-3.7.1.jar (com.google.protobuf:protobuf-java:3.7.1) and protobuf-lite-3.0.1.jar (com.google.protobuf:protobuf-lite:3.0.1)
Duplicate class com.google.protobuf.BooleanArrayList found in modules protobuf-java-3.7.1.jar (com.google.protobuf:protobuf-java:3.7.1) and protobuf-lite-3.0.1.jar (com.google.protobuf:protobuf-lite:3.0.1)
Duplicate class com.google.protobuf.ByteBufferWriter found in modules protobuf-java-3.7.1.jar (com.google.protobuf:protobuf-java:3.7.1) and protobuf-lite-3.0.1.jar (com.google.protobuf:protobuf-lite:3.0.1)
Duplicate class com.google.protobuf.ByteOutput found in modules protobuf-java-3.7.1.jar (com.google.protobuf:protobuf-java:3.7.1) and protobuf-lite-3.0.1.jar (com.google.protobuf:protobuf-lite:3.0.1)
Duplicate class com.google.protobuf.ByteString found in modules protobuf-java-3.7.1.jar (com.google.protobuf:protobuf-java:3.7.1) and protobuf-lite-3.0.1.jar (com.google.protobuf:protobuf-lite:3.0.1)
Duplicate class com.google.protobuf.ByteString$1 found in modules protobuf-java-3.7.1.jar (com.google.protobuf:protobuf-java:3.7.1) and protobuf-lite-3.0.1.jar (com.google.protobuf:protobuf-lite:3.0.1)

Answer 1

缺少的类是 known issue . full proto 和 lite proto 不能混用；他们使用不同的生成代码。不要依赖 protobuf-java 作为 implementation依赖，但作为 protobuf将导致 gradle-protobuf-plugin 为 .protos 生成代码的依赖项.

dependencies {
  ...
  protobuf 'com.google.protobuf:protobuf-java:3.7.1'
}

请注意，此解决方案仅适用于应用程序。如果你是一个库，这是很危险的，因为你的库的用户可能会看到为众所周知的 protos 生成的代码的多个副本。