java中对于账号密码加密--sha_1和sha256总结

sha加密算法

sha加密算法比MD5加密更加安全。

sha1加密算法

加密密文长度40位。

	/*sha1加密*/
	public static String sha1(String decript) {
	    try {
	        MessageDigest digest = MessageDigest
	                .getInstance("SHA-1");
	        digest.update(decript.getBytes());
	        byte messageDigest[] = digest.digest();
	        // Create Hex String
	        StringBuffer hexString = new StringBuffer();
	        // 字节数组转换为 十六进制 数
	        for (int i = 0; i < messageDigest.length; i++) {
	            String shaHex = Integer.toHexString(messageDigest[i] & 0xFF);
	            if (shaHex.length() < 2) {
	                hexString.append(0);
	            }
	            hexString.append(shaHex);
	        }
	        return hexString.toString();
	 
	    } catch (NoSuchAlgorithmException e) {
	        e.printStackTrace();
	    }
	    return "";
	}

sha256加密算法

密文长度64位

package com.zyhd.util;
 
import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
 
public class Sha256 {
 
	/**
	 * 利用java原生的类实现SHA256加密
	 * 
	 * @param str 加密后的报文
	 * @return
	 */
	public static String getSHA256(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();
	}
}