简单的java加密解密类

import java.security.Key;import java.security.NoSuchAlgorithmException;import java.security.SecureRandom;import javax.crypto.Cipher;import javax.crypto.KeyGenerator;import javax.crypto.SecretKey;import javax.crypto.spec.SecretKeySpec;public class CryptUtil {private static final CryptUtil instance = new CryptUtil();private CryptUtil() {}public static CryptUtil getInstance() {return instance;}private Key initKeyForAES(String key) throws NoSuchAlgorithmException {if (null == key || key.length() == 0) {throw new NullPointerException("key not is null");}SecretKeySpec key2 = null;try {KeyGenerator kgen = KeyGenerator.getInstance("AES");kgen.init(128, new SecureRandom(key.getBytes()));SecretKey secretKey = kgen.generateKey();byte[] enCodeFormat = secretKey.getEncoded();key2 = new SecretKeySpec(enCodeFormat, "AES");} catch (NoSuchAlgorithmException ex) {throw new NoSuchAlgorithmException();}return key2;}/** * AES加密算法，不受密钥长度限制 * @param content * @param key * @return */public String encryptAES(String content, String key){try{SecretKeySpec secretKey = (SecretKeySpec) initKeyForAES(key);Cipher cipher = Cipher.getInstance("AES");// 创建密码器byte[] byteContent = content.getBytes("utf-8");cipher.init(Cipher.ENCRYPT_MODE, secretKey);// 初始化byte[] result = cipher.doFinal(byteContent);return asHex(result); // 加密}catch (Exception e){e.printStackTrace();}return null;}/** * aes解密算法，不受密钥长度限制 * @param content * @param key * @return */public String decryptAES(String content, String key){try{SecretKeySpec secretKey = (SecretKeySpec) initKeyForAES(key);Cipher cipher = Cipher.getInstance("AES");// 创建密码器cipher.init(Cipher.DECRYPT_MODE, secretKey);// 初始化byte[] result = cipher.doFinal(asBytes(content));return new String(result); // 加密}catch (Exception e){e.printStackTrace();}return null;}/** * 将2进制数值转换为16进制字符串 * @param buf * @return */public String asHex(byte buf[]){StringBuffer strbuf = new StringBuffer(buf.length * 2);int i;for (i = 0; i < buf.length; i++){if (((int) buf[i] & 0xff) < 0x10)strbuf.append("0");strbuf.append(Long.toString((int) buf[i] & 0xff, 16));}return strbuf.toString();}    /** * 将16进制转换 * @param hexStr * @return */public byte[] asBytes(String hexStr) {if (hexStr.length() < 1)return null;byte[] result = new byte[hexStr.length() / 2];for (int i = 0; i < hexStr.length() / 2; i++){int high = Integer.parseInt(hexStr.substring(i * 2, i * 2 + 1), 16);int low = Integer.parseInt(hexStr.substring(i * 2 + 1, i * 2 + 2),16);result[i] = (byte) (high * 16 + low);}return result;}public static void main(String[] args)  {CryptUtil crypt = CryptUtil.getInstance();String content = "asdfsdfdsfds|33333443";System.out.println(crypt.encryptAES(content, "aaa22"));String dcontent = crypt.encryptAES(content, "aaa22");System.out.println(crypt.decryptAES(dcontent, "aaa22"));}}