/**
* 簽名演算法
* @author zhoujia
* @date 2017-9-8
* @todo TODO
* @param data  需要簽名的內容
* @param keyStoreFileName  含私鑰的檔案
* @param keyStorePassword  含私鑰檔案的密碼
* @param keyStoreAlias  別名
* @return
*/
public static String signData(String data,String keyStoreFileName,String keyStorePassword,String keyStoreAlias)
{
KeyStore keyStore;
byte[]  signRstByte=null;
String signValue="";
try {
keyStore = KeyStore.getInstance("PKCS12");//獲取pfx證書例項  當證書為jks 格式時引數應當為JKS
FileInputStream in=new FileInputStream(keyStoreFileName);//獲取證書檔案流
char[]pwdChar=keyStorePassword.toCharArray();//證書密碼
keyStore.load(in, pwdChar);//載入證書到keystore中

 Enumeration enumas = keyStore.aliases();  

    //此處不知道別名。（如有固定別名則直接用）

           String keyAlias = null;   
           if (enumas.hasMoreElements())// we are readin just one certificate.  
           {  
               keyAlias = (String)enumas.nextElement();   
               DevLogger.tradeLog("alias=[" + keyAlias + "]");  

           } 

PrivateKey privateKey=(PrivateKey)keyStore.getKey(keyAlias, pwdChar);//從證書中獲取私鑰
Signature sign=Signature.getInstance("SHA1WithRSA");//SHA1WithRSA簽名演算法
sign.initSign(privateKey);//設定私鑰
sign.update(data.getBytes());//設定明文
signRstByte=sign.sign();//加密
BASE64Encoder encoder=new BASE64Encoder();
signValue=encoder.encodeBuffer(signRstByte);//BASE64編碼
//System.out.println("簽名並編碼後的內容signValue=="+signValue);
} catch (KeyStoreException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (NoSuchAlgorithmException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (CertificateException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (UnrecoverableKeyException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (InvalidKeyException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SignatureException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return signValue;


}