AndroidR 修改framework後如何快速模塊編譯

AndroidR 修改framework後如何快速模塊編譯

最近工作安排android大版本升級，需要將androidQ上的framework修改移植到androidR上。

移植後，整個工程全部make編譯太耗費時間了，於是經驗性的使用模塊編譯命令make framework進行模塊單編。然而，雖然提示編譯成功，但在out目錄下並沒有相應的framework.jar包生成。看來android11在此處進行了改動。

對比androidQ和androidR的frameworks/base/Android.bp文件，發現Android.bp文件做了不小的修改。

擷取其中一段對我們編譯有幫助的配置及註釋，如下：

java_library {
   
   
    name: "framework-minus-apex",
    defaults: ["framework-defaults"],
    srcs: [":framework-non-updatable-sources"],
    installable: true,
    javac_shard_size: 150,
    required: [
        "framework-platform-compat-config",
        "libcore-platform-compat-config",
        "services-platform-compat-config",
        "documents-ui-compat-config",
    ],
    libs: ["framework-updatable-stubs-module_libs_api"],
    static_libs: [
        // If MimeMap ever becomes its own APEX, then this dependency would need to be removed
        // in favor of an API stubs dependency in java_library "framework" below.
        "mimemap",
    ],
    // For backwards compatibility.
    stem: "framework",
    apex_available: ["//apex_available:platform"],
    visibility: [
        "//frameworks/base",
        // TODO(b/147128803) remove the below lines
        "//frameworks/base/apex/blobstore/framework",
        "//frameworks/base/apex/jobscheduler/framework",
        "//frameworks/base/packages/Tethering/tests/unit",
    ],
}

// This "framework" module is NOT installed to the device. It's
// "framework-minus-apex" that gets installed to the device. Note that
// the filename is still framework.jar (via the stem property) for
// compatibility reason. The purpose of this module is to provide
// framework APIs (both public and private) for bundled apps.
// "framework-minus-apex" can't be used for the purpose because 1)
// many apps have already hardcoded the name "framework" and
// 2) it lacks API symbols from updatable modules - as it's clear from
// its suffix "-minus-apex".
java_library {
   
   
    name: "framework",
    defaults: ["framework-aidl-export-defaults"],
    installable: false, // this lib is a build-only library
    static_libs: [
        "app-compat-annotations",
        "framework-minus-apex",
        "framework-updatable-stubs-module_libs_api",
    ],
    sdk_version: "core_platform",
    apex_available: ["//apex_available:platform"],
}

通過反覆理解此bp文件，對谷歌工程師的想法似乎可以揣摩一二了。

於是嘗試採用下面的模塊編譯命令（可以加-j8/-j16指定編譯線程數）：

make framework-minus-apex

果不其然，順利編譯出了frameowrk.jar包：

[100% 1155/1155] Install: out/target/product/PorjectAndroidR/system/framework/framework.jar
#### build completed successfully (04:50 (mm:ss)) ####

爲文以記之。

2020年12月末，於青島。

感謝：
[1]: https://blog.csdn.net/zhzhangnews/article/details/105634037