大部分來自於
http://developer.android.com/sdk/installing/studio-build.html
gradle build 會生成默認的debug版本 和 release 版本
gradle assemblerelease 不生成debug版本，只生成release版本
gradle assembledebug 不生成release版本，只生成debug版本
可以在下面的命令顯示出得結果中看到版本的意思。
查看所有的task ，命令 ：
gradle tasks
osdeMacBook-Pro:app os$ gradle tasks
:app:tasks
------------------------------------------------------------
All tasks runnable from project :app
------------------------------------------------------------
Android tasks
-------------
androidDependencies - Displays the Android dependencies of the project
signingReport - Displays the signing info for each variant
Build tasks
-----------
assemble - Assembles all variants of all applications and secondary packages.
assembleDebug - Assembles all Debug builds
assembleHiapk - Assembles all Hiapk builds
assembleHiapkDebug - Assembles the Debug build for flavor Hiapk
assembleHiapkDebugTest - Assembles the Test build for the HiapkDebug build
assembleHiapkRelease - Assembles the Release build for flavor Hiapk
assemblePlaystore - Assembles all Playstore builds
assemblePlaystoreDebug - Assembles the Debug build for flavor Playstore
assemblePlaystoreDebugTest - Assembles the Test build for the PlaystoreDebug build
assemblePlaystoreRelease - Assembles the Release build for flavor Playstore
assembleRelease - Assembles all Release builds
assembleTest - Assembles all the Test applications
build - Assembles and tests this project.
buildDependents - Assembles and tests this project and all projects that depend on it.
buildNeeded - Assembles and tests this project and all projects it depends on.
clean - Deletes the build directory.
Help tasks
----------
components - Displays the components produced by project ':app'.
dependencies - Displays all dependencies declared in project ':app'.
dependencyInsight - Displays the insight into a specific dependency in project ':app'.
help - Displays a help message
projects - Displays the sub-projects of project ':app'.
properties - Displays the properties of project ':app'.
tasks - Displays the tasks runnable from project ':app'.
Install tasks
-------------
installHiapkDebug - Installs the Debug build for flavor Hiapk
installHiapkDebugTest - Installs the Test build for the HiapkDebug build
installHiapkRelease - Installs the Release build for flavor Hiapk
installPlaystoreDebug - Installs the Debug build for flavor Playstore
installPlaystoreDebugTest - Installs the Test build for the PlaystoreDebug build
installPlaystoreRelease - Installs the Release build for flavor Playstore
uninstallAll - Uninstall all applications.
uninstallHiapkDebug - Uninstalls the Debug build for flavor Hiapk
uninstallHiapkDebugTest - Uninstalls the Test build for the HiapkDebug build
uninstallHiapkRelease - Uninstalls the Release build for flavor Hiapk
uninstallPlaystoreDebug - Uninstalls the Debug build for flavor Playstore
uninstallPlaystoreDebugTest - Uninstalls the Test build for the PlaystoreDebug build
uninstallPlaystoreRelease - Uninstalls the Release build for flavor Playstore
Verification tasks
------------------
check - Runs all checks.
connectedAndroidTest - Installs and runs instrumentation tests for all flavors on connected devices.
connectedAndroidTestHiapkDebug - Installs and runs the tests for Build 'hiapkDebug' on connected devices.
connectedAndroidTestPlaystoreDebug - Installs and runs the tests for Build 'playstoreDebug' on connected devices.
connectedCheck - Runs all device checks on currently connected devices.
deviceAndroidTest - Installs and runs instrumentation tests using all Device Providers.
deviceCheck - Runs all device checks using Device Providers and Test Servers.
lint - Runs lint on all variants.
lintHiapkDebug - Runs lint on the HiapkDebug build
lintHiapkRelease - Runs lint on the HiapkRelease build
lintPlaystoreDebug - Runs lint on the PlaystoreDebug build
lintPlaystoreRelease - Runs lint on the PlaystoreRelease build
Other tasks
-----------
compileHiapkDebugSources
compileHiapkDebugTestSources
compileHiapkReleaseSources
compilePlaystoreDebugSources
compilePlaystoreDebugTestSources
compilePlaystoreReleaseSources
Rules
-----
Pattern: clean<TaskName>: Cleans the output files of a task.
Pattern: build<ConfigurationName>: Assembles the artifacts of a configuration.
Pattern: upload<ConfigurationName>: Assembles and uploads the artifacts belonging to a configuration.
To see all tasks and more detail, run with --all.
BUILD SUCCESSFUL
Total time: 8.967 secs
然後，在build tasks 中選取需要單獨bulid的命令
有中文翻譯版本在這，gradle編譯