MD5生成

package test;

import java.security.MessageDigest;

public class Md5Digest 
{
	public static String md5(String string) 
	{
		char hexDigits[] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd',
		'e', 'f' };
		try {
			byte[] bytes = string.getBytes();
			MessageDigest messageDigest = MessageDigest.getInstance("MD5");
			messageDigest.update(bytes);
			byte[] updateBytes = messageDigest.digest();
			int len = updateBytes.length;
			char myChar[] = new char[len * 2];
			int k = 0;
			for (int i = 0; i < len; i++) {
				byte byte0 = updateBytes[i];
				myChar[k++] = hexDigits[byte0 >>> 4 & 0x0f];
				myChar[k++] = hexDigits[byte0 & 0x0f];
			}
		return new String(myChar);
		} catch (Exception e) {
		return null;
		}
	}
        /**
	 * 删除input字符串中的html格式
	 * 
	 * @param input
	 * @param length
	 * @return
	 */
	public static String splitAndFilterString(String input, int length) {
		if (input == null || input.trim().equals("")) {
			return "";
		}
		// 去掉所有html元素,
		String str = input.replaceAll("\\&[a-zA-Z]{1,10};", "").replaceAll(
				"<[^>]*>", "");
		str = str.replaceAll("[/><]", "");
		int len = str.length();
		if (len <= length) {
			return str;
		} else {
			str = str.substring(0, length);
			str += "......";
		}
		return str;
	}
	
	public static void main(String[] arg)
	{
		System.out.println(Md5Digest.md5("111111"));
	}

}