Java常用工具类---Random随机数工具类、MD5加密工具类

川长思鸟来 2022-01-29 09:53 303阅读 0赞

package com.jarvis.base.util;
    
    import java.util.Random;
    
    /**
     *   
     * 
     * @Title: RandomHelper.java
     * @Package com.jarvis.base.util
     * @Description: 随机数工具类
     * @version V1.0  
     */
    public class RandomHelper {
    	/**
    	 * RANDOM 基数
    	 */
    	private final static int RANDOM_BASE = 10;
    
    	/**
    	 * 产生指定长度的数字值随机数
    	 *
    	 * @param length
    	 *            需要产生的长度
    	 * @return
    	 */
    	public static String getRandomStr(int length) {
    		Random random = new Random();
    		String randStr = "";
    		for (int i = 0; i < length; i++) {
    			String randItem = String.valueOf(random.nextInt(RANDOM_BASE));
    			randStr += randItem;
    		}
    		return randStr;
    	}
    
    	/**
    	 * 描述：手机验证码生成带字符，包含数字和字符 作者： 时间：Oct 29, 2008 3:40:07 PM
    	 * 
    	 * @param len
    	 *            生成手机验证码长度
    	 * @return
    	 */
    	public static String generateChatAndNumberIdentifyCode(int len) {
    		char[] identifyStr = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
    				'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z' };
    		// char[] identifyStr={'0','1','2','3','4','5','6','7','8','9'};
    		// 生成随机类
    		// Random random = new Random();
    		int min = 0;
    		int maxnum = identifyStr.length;
    		String codeStr = "";
    		for (int i = 0; i < len; i++) {
    			int num = (int) ((maxnum - min) * Math.random() + min);
    			codeStr += identifyStr[num];
    		}
    		return codeStr;
    	}
    
    	/**
    	 * 描述：手机验证码生成带字符不包含数字
    	 * 
    	 * @param len
    	 *            生成手机验证码长度
    	 * @return
    	 */
    	public static String generateIdentifyCode(int len) {
    		char[] identifyStr = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R',
    				'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z' };
    		// char[] identifyStr={'0','1','2','3','4','5','6','7','8','9'};
    		// 生成随机类
    		// Random random = new Random();
    		int min = 0;
    		int maxnum = identifyStr.length;
    		String codeStr = "";
    		for (int i = 0; i < len; i++) {
    			int num = (int) ((maxnum - min) * Math.random() + min);
    			codeStr += identifyStr[num];
    		}
    		return codeStr;
    	}
    
    }
    
    
    
    package com.jarvis.base.util;
    import java.security.MessageDigest;
    
    public class MD5Util {
        /**
         * Title: MD5加密 生成32位md5码
         * Description: TestDemo
         * @param inStr
         * @return 返回32位md5码
         * @throws Exception
         */
        public static String md5Encode(String inStr) throws Exception {
            MessageDigest md5 = null;
            try {
                md5 = MessageDigest.getInstance("MD5");
            } catch (Exception e) {
                System.out.println(e.toString());
                e.printStackTrace();
                return "";
            }
            byte[] byteArray = inStr.getBytes("UTF-8");
            byte[] md5Bytes = md5.digest(byteArray);
            StringBuffer hexValue = new StringBuffer();
            for (int i = 0; i < md5Bytes.length; i++) {
                int val = ((int) md5Bytes[i]) & 0xff;
                if (val < 16) {
                    hexValue.append("0");
                }
                hexValue.append(Integer.toHexString(val));
            }
            return hexValue.toString();
        }
        /**
         * Title: MD5加密
         * Description: TestDemo
         * @author lu
         * @date 2016年6月23日 下午2:43:31
         * @param inStr
         * @return
         */
        public static String md5(String inStr) {
            MessageDigest md5 = null;
            try {
                md5 = MessageDigest.getInstance("MD5");
            } catch (Exception e) {
                System.out.println(e.toString());
                e.printStackTrace();
                return "";
            }
            char[] charArray = inStr.toCharArray();
            byte[] byteArray = new byte[charArray.length];
    
            for (int i = 0; i < charArray.length; i++)
                byteArray[i] = (byte) charArray[i];
            byte[] md5Bytes = md5.digest(byteArray);
            StringBuffer hexValue = new StringBuffer();
            for (int i = 0; i < md5Bytes.length; i++) {
                int val = ((int) md5Bytes[i]) & 0xff;
                if (val < 16)
                    hexValue.append("0");
                hexValue.append(Integer.toHexString(val));
            }
            return hexValue.toString();
    
        }
    
        /**
         * Title: 加密解密算法 执行一次加密，两次解密
         * Description: TestDemo
         * @author lu
         * @date 2016年6月23日 下午2:37:29
         * @param inStr
         * @return
         */
        public static String convertMD5(String inStr) {
    
            char[] a = inStr.toCharArray();
            for (int i = 0; i < a.length; i++) {
                a[i] = (char) (a[i] ^ 't');
            }
            String s = new String(a);
            return s;
    
        }
        public static String md5Decode(String str) {
            return convertMD5(convertMD5(str));
        }
    
        public static void main(String[] args) {
            String s = new String("13917114404");
            System.out.println(md5Decode("a6aeb3ffa55fc7d664406af9c3bd0f1b"));
            System.out.println("原始：" + s);
            System.out.println("MD5后：" + md5(s));
            System.out.println("加密的：" + convertMD5(s));
            System.out.println("解密的：" + convertMD5(convertMD5(s)));
            System.out.println(md5("13917114404"));
        }
    }