HelperUtil using a IMPL

HelperUtil.java

public class HelperUtil {

    private final HelperUtilImpl mImpl;

    public  HelperUtil (Context context) {

        if (Build.VERSION.SDK_INT > Build.VERSION_CODES.KITKAT) {
            mImpl =  new HelperUtilImplL(context);
        } else if (Build.VERSION.SDK_INT == Build.VERSION_CODES.KITKAT) {
            mImpl = new HelperUtilImplKK(context);
        } else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
            mImpl = new HelperUtilImplJB(context);
        } else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
            mImpl = new HelperUtilImplICS(context);
        } else {
            mImpl = new HelperUtilImplBase(context);
        }
    }

    public void setActionBar() {
        mImpl.setActionBar();
    }

    public void setElevation(View view, float elevation){
        mImpl.setElevation(view, elevation);
    }

}

HelperUtilImpl.java

public interface HelperUtilImpl {

    public void setActionBar();

    public void setElevation(View view, float elevation);


}

HelperUtilImplBase.java

public class HelperUtilImplBase implements HelperUtilImpl{

    protected Context mContext;

    public HelperUtilImplBase(Context context){
        this.mContext = context;
    }

    public void setActionBar() {
        // Do nothing pre-L
    }

    public void setElevation(View view, float elevation){
        // Do nothing pre-L
    }

}

HelperUtilImplKK.java

@TargetApi(Build.VERSION_CODES.KITKAT)
public class HelperUtilImplKK extends HelperUtilImplBase{

    public HelperUtilImplKK(Context context){
        super(context);
    }

}

HelperUtilImplL.java

@TargetApi(Build.VERSION_CODES.L)
public class HelperUtilImplL extends HelperUtilImplBase{

    private Toolbar mActionBarToolbar;

    public HelperUtilImplL(Context context){
        super(context);
    }

    @Override
    public void setElevation(View view, float elevation){
        view.setElevation(elevation);
    }

    @Override
    public void setActionBar() {
        mActionBarToolbar = (Toolbar) ((Activity)mContext).findViewById(R.id.toolbar);
        if (mActionBarToolbar != null) {
            ((Activity)mContext).setActionBar(mActionBarToolbar);
        }
    }


}

SimpleActivity.java

public class SimpleActivity extends Activity {

    HelperUtil helper;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        helper = new HelperUtil(this);
        
        //........
        
        helper.setElevation(view, 2.0f);
        helper.setActionBar();
    }
}