Staying out of deprecated methods is useful, so your app won’t run in some compatibility mode on the device. Plus having clean build output is also nice 🙂

While building an app, Gradle may produces some warnings telling you that some input files are using unchecked or unsafe operations or they are overriding a deprecated API.

Note: Some input files use unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.

Note: Some input files use or override a deprecated API.
Note: Recompile with -Xlint:deprecation for details.

As the message suggest, we should recompile with -Xlint to get more details about the warnings.

In the app level build.gradle file

app level build.gradle file

we should add a section labelled  allprojects{}(if not already present).

In the allprojects{} section we will instruct Gradle to apply custom compiler arguments for each task involving  Java code compilation.

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

Now each time we build our app we will get detailed output of the unchecked or unsafe operations and the deprecated API we are using.

Tip: if for some reason we want to continue using a deprecated API and just suppress the warnings, we could annotate the deprecated method with the

@SuppressWarnings("deprecation")

annotation.