Check https://developer.android.com/studio/releases/platforms
if(android.os.Build.VERSION.SDK_INT == android.os.Build.VERSION_CODES.LOLLIPOP){
// Code For Android Version higher equal to LOLLIPOP(21)
} else if(android.os.Build.VERSION.SDK_INT > 21){
// Code For Android Version higher than LOLLIPOP(21)
} else{
// Code For Android Version lower than LOLLIPOP(21)
}