SHA256算法

/**
 *  利用java原生的摘要实现SHA256加密
 * @param str 加密后的报文
 * @return
 */
public String getSHA256StrJava(String str){
    MessageDigest messageDigest;
    String encodeStr = "";
    try {
        messageDigest = MessageDigest.getInstance("SHA-256");
        messageDigest.update(str.getBytes("UTF-8"));
        encodeStr = byte2Hex(messageDigest.digest());
    } catch (NoSuchAlgorithmException e) {
        e.printStackTrace();
    } catch (UnsupportedEncodingException e) {
        e.printStackTrace();
    }
    return encodeStr;
}

/**
 * 将byte转为16进制
 * @param bytes
 * @return
 */
private String byte2Hex(byte[] bytes){
    StringBuffer stringBuffer = new StringBuffer();
    String temp = null;
    for (int i=0;ilength;i++){
        temp = Integer.toHexString(bytes[i] & 0xFF);
        if (temp.length()==1){
            //1得到一位的进行补0操作
            stringBuffer.append("0");
        }
        stringBuffer.append(temp);
    }
    return stringBuffer.toString();
}