How to add java compiler options when compiling wi

问题:

I have a build.gradle file with dependencies { classpath 'com.android.tools.build:gradle:0.13.3'} and apply plugin: 'com.android.application'.

When I do a debug build I get:

gradle clean assembleDebug
:myapp:preBuild
(...)
:myapp:compileDebugJava
Note: C:\path\to\MyClass.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.

:myapp:preDexDebug
(...)
:myapp:assembleDebug

BUILD SUCCESSFUL

How can I add the -Xlint:unchecked to the underlying task? Gradle Plugin User Guide on Java compilation options is unhelpful.

回答1:

I tried the solution posed by @Konrad Jamrozik but it didn't work with my project due to flavours in my project.

Given that we're just turning on additional warnings, not something that's significantly changing how the compiler operates, I don't see it being an issue that it will be added to both release and debug builds. As such, this answer has a cleaner method that works with flavours: How to add -Xlint:unchecked to my Android Gradle based project?

In my case, adding this to the build.gradle file of the affected module:

gradle.projectsEvaluated {
   tasks.withType(JavaCompile) {
        options.compilerArgs << "-Xlint:unchecked" << "-Xlint:deprecation"
    }
}

回答2:

I found the following solution based on Gradle Plugin User Guide on Manipulating Tasks and Gradle DSL doc about JavaCompile:

Add to build.gradle:

preBuild {
    doFirst {
        JavaCompile jc = android.applicationVariants.find { it.name == 'debug' }.javaCompile
        jc.options.compilerArgs = ["-Xlint:unchecked"]
    }
}

The application variants are null during Gradle's configuration phase and the required JavaCompile task also doesn't exist, thus I do the modification in the execution phase instead.

回答3:

Add this to build.gradle file:

android { // <---
   tasks.withType(JavaCompile) {
      configure(options) {
         options.encoding = 'UTF-8'
         options.debug = true
         options.failOnError = true
         options.warnings = true
         options.compilerArgs << '-Xlint:deprecation' << '-Xlint:unchecked'
   }
}