/**
* 解密 由于RSA一次只能加密128个字节（加密后也是128个字节），所以将密文按128个字节分割，分块解密，最后将解密后的字节流连接起来。 (non-Javadoc)
*
* @see com.alipay.api.security.Encrypt#decrypt(java.lang.String, java.lang.String,
* java.lang.String, com.alipay.api.enums.EncryptStyleEnum)
*/
public String decrypt(String content, String key) throws Exception {
PrivateKey prikey =
KeyReader.getPrivateKeyFromPKCS8(ALGORITHM, new ByteArrayInputStream(key.getBytes()));
Cipher cipher = Cipher.getInstance(CIPHER_NAME);
cipher.init(Cipher.DECRYPT_MODE, prikey);
InputStream ins = new ByteArrayInputStream(Base64.decodeBase64(content.getBytes()));
ByteArrayOutputStream writer = new ByteArrayOutputStream();
byte[] buf = new byte[128];
int bufl;
while ((bufl = ins.read(buf)) != -1) {
byte[] block = null;
if (buf.length == bufl) {
block = buf;
} else {
block = new byte[bufl];
for (int i = 0; i < bufl; i++) {
block[i] = buf[i];
}
}
writer.write(cipher.doFinal(block));
}
return new String(writer.toByteArray(), "utf-8");
}
