如何获得Android系统版本

项目移植中，遇到需要区分不同系统版本的问题。于是查找相关方法如下：

android.os.Build类提供了当前系统信息。
可用if (Build.VERSION.SDK_INT < Build.VERSION_CODES.GINGERBREAD)这样来判断。

有人用这样一个函数来获取版本号：

public static int getAndroidSDKVersion() {
int version;
try {
version = Integer.valueOf(android.os.Build.VERSION.SDK);
} catch (NumberFormatException e) {
Log.e(e.toString());
}
return version;
}

android.os.Build.VERSION_CODES 值有如下，其中第二列的值就是API LEVEL编号：

int	1 (0x00000001)	BASE	October 2008: The original, first, version of Android.
int	2 (0x00000001)	BASE_1_1	February 2009: First Android update, officially called 1.1.
int	3 (0x00000001)	CUPCAKE	May 2009: Android 1.5.
int	10000 (0x00002710)	CUR_DEVELOPMENT	Magic version number for a current development build, which has not yet turned into an official release.
int	5 (0x00000001)	DONUT	September 2009: Android 1.6.
int		ECLAIR	November 2009: Android 2.0
			Applications targeting this or a later release will get these new changes in behavior:
	5 (0x00000008)		The Service.onStartCommand function will return the new START_STICKY behavior instead of the old compatibility START_STICKY_COMPATIBILITY.
int	6 (0x00000008)	ECLAIR_0_1	December 2009: Android 2.0.1
int	7 (0x00000008)	ECLAIR_MR1	January 2010: Android 2.1
int	8 (0x00000008)	FROYO	June 2010: Android 2.2
int		GINGERBREAD	November 2010: Android 2.3
			Applications targeting this or a later release will get these new changes in behavior:
	9 (0x00000009)		The application's notification icons will be shown on the new dark status bar background, so must be visible in this situation.
int	10 (0x0000000a)	GINGERBREAD_MR1	February 2011: Android 2.3.3.
int	11 (0x0000000b)	HONEYCOMB	February 2011: Android 3.0.
int	12 (0x0000000c)	HONEYCOMB_MR1	May 2011: Android 3.1.
int	13 (0x0000000d)	HONEYCOMB_MR2	June 2011: Android 3.2.
int	14 (0x0000000e)	ICE_CREAM_SANDWICH	October 2011: Android 4.0.
int	15 (0x0000000f)	ICE_CREAM_SANDWICH_MR1	December 2011: Android 4.0.3.
int	16 (0x00000010)	JELLY_BEAN	Android 4.1.