Java SHA-256加密的两种实现方法详解

<dependency>
 <groupId>commons-codec</groupId>
 <artifactId>commons-codec</artifactId>
 <version>${common-codec.version}</version>
</dependency>

/***
* 利用Apache的工具类实现SHA-256加密
* @param str 加密后的报文
* @return
*/
public static String getSHA256Str(String str){
 MessageDigest messageDigest;
 String encdeStr = "";
 try {
  messageDigest = MessageDigest.getInstance("SHA-256");
  byte[] hash = messageDigest.digest(str.getBytes("UTF-8"));
  encdeStr = Hex.encodeHexString(hash);
 } catch (NoSuchAlgorithmException e) {
  e.printStackTrace();
 } catch (UnsupportedEncodingException e) {
  e.printStackTrace();
 }
 return encdeStr;
}

/**
* 利用java原生的摘要实现SHA256加密
* @param str 加密后的报文
* @return
*/
public static 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 static String byte2Hex(byte[] bytes){
 StringBuffer stringBuffer = new StringBuffer();
 String temp = null;
 for (int i=0;i<bytes.length;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();
}