Best Way to Include Debug Code?

I am programming Android applications, and the best way here may or may not be the same as Java in general.

I simply want to be able to set a debug flag that will on开发者_开发技巧ly execute certain portions of code when it's set to true––equiv to C++ setting a preprocessor #define DEBUG and using #ifdef DEBUG.

Is there an accepted or best way to accomplish this in Java?

Right now I'm just going to set a variable in my Application object, but I don't imagine this is the best way.

Instead of using your own flag, you can use the flag set automatically by ADT, like this:

final static int appFlags = context.getApplicationInfo().flags;
final static boolean isDebug = (appFlags & ApplicationInfo.FLAG_DEBUGGABLE) != 0

The FLAG_DEBUGGABLE bit is automatically set to true or false, depending on the "debuggable" attribute of the application (set in AndroidManifest.xml). The latest version of ADT (version 8) automatically sets this attribute for you when not exporting a signed package.

Thus, you don't have to remember setting / resetting your own custom flag.

You can read more in this thread.

That's the way I do it:

// in some.class.with.Constants
public static final boolean DEV_MODE = true;

// in some other class
import static some.class.with.Constants.DEV_MODE;

if(DEV_MODE){
    Log.d('sometag', 'somemessage');
}

I suggest to use inbuilt android API BuildConfig

if (BuildConfig.DEBUG) {
  // do something for a debug build
}

Revision 17 of SDK tools (March 2012) introduced a way to imitate C's #ifdef DEBUG

From the General Notes:

Added a feature that allows you to run some code only in debug mode. Builds now generate a class called BuildConfig containing a DEBUG constant that is automatically set according to your build type. You can check the (BuildConfig.DEBUG) constant in your code to run debug-only functions.

This works for me with code if (BuildConfig.DEBUG), using the BuildConfig class. This is a safe and easy code to do. Be careful when using this style of code. Don't use it such that there are 2 different distinct branches of code, between Release and Debug versions. If you do, it might invalidate the app testing for the Release version. For me, I have used it only to skip calling Log messaging.

More details on this class BuildConfig @ Build System Concepts.

if ( Debug.isDebuggerConnected() ) {
  // debug stuff
}

I think that writing tests is better alternative than adding DEBUG code.

My point is that when you write test for some component/method/class you don't pollute your original source code with some redundant debug code.