import?java.io.InputStream;
import?java.security.DigestInputStream;
import?java.security.MessageDigest;

public?class?GetFileSHA1?{
	/**
	?*?獲取文件SHA1摘要值
	?*?@param?fileInputStream
	?*?@return
	?*/
	public?static?String?getSHA1（InputStream?fileInputStream）{
		//?緩沖區(qū)大小
????????int?bufferSize?=?256?*?1024;
????????DigestInputStream?digestInputStream?=?null;
????????try{
???????????//?拿到一個SHA1轉(zhuǎn)換器（這里可以換成MD5）
???????????MessageDigest?messageDigest?=MessageDigest.getInstance（“SHA1“）;
???????????//?使用DigestInputStream
???????????digestInputStream?=?new?DigestInputStream（fileInputStreammessageDigest）;
???????????//?read的過程中進行SHA1處理，直到讀完文件
???????????byte[]?buffer?=new?byte[bufferSize];
???????????while?（digestInputStream.read（buffer）?>?0）;
???????????//?獲取最終的MessageDigest
???????????messageDigest=?digestInputStream.getMessageDigest（）;
???????????//?拿到結(jié)果，也是字節(jié)數(shù)組，包含16個元素
???????????byte[]?resultByteArray?=?messageDigest.digest（）;
???????????//?把字節(jié)數(shù)組轉(zhuǎn)換成字符串
???????????retur