public static String sign(String priKey, String data, String encoding){
String text = null;
if (data == null){
System.out.println("生成数字签名错：签名源串为空");
return null;
}
if (encoding == null || encoding.trim().equals("")){
encoding = "UTF-8";
}
//获取签名对象
try{
System.out.println(data);
byte[] plainText = data.getBytes(encoding);
PKCS8EncodedKeySpec priPKCS8 = new PKCS8EncodedKeySpec(Base64.decode(priKey));
KeyFactory keyf = KeyFactory.getInstance("RSA");
Signature signer=Signature.getInstance("MD5WithRSA");
signer.initSign(keyf.generatePrivate(priPKCS8));
signer.update(plainText);
byte[] signature=signer.sign();
text = Base64.encodeBytes(signature);
}catch (Exception e){
System.out.println("生成数字签名错:"+e.getMessage());
return null;
}
return text;
}