错误原因

当我们使用maven-publish插件上传Java Library的时候，配置一般使用from components.java。如下所示

publishing {
    publications {
        maven(MavenPublication) {
            groupId = pluginGroupId
            artifactId = pluginArtifactId
            version = pluginVersion

            from components.java
        }
    }
}

当在Android Library中这样配置会报错如下

A problem occurred evaluating project ':library'.
> Could not get unknown property 'java' for SoftwareComponentInternal set of type org.gradle.api.internal.component.DefaultSoftwareComponentContainer.

修复方案

publishing {
    publications {
        maven(MavenPublication) {
            groupId = pluginGroupId
            artifactId = pluginArtifactId
            version = pluginVersion

            artifact("$buildDir/outputs/aar/${project.name}-release.aar")
        }
    }
}