java基于AES对称加密算法实现的加密与解密功能示例

package com.soufun.com;import java.io.UnsupportedEncodingException;import java.security.InvalidKeyException;import java.security.NoSuchAlgorithmException;import java.security.SecureRandom;import java.util.Date;import javax.crypto.BadPaddingException;import javax.crypto.Cipher;import javax.crypto.IllegalBlockSizeException;import javax.crypto.KeyGenerator;import javax.crypto.NoSuchPaddingException;import javax.crypto.SecretKey;import javax.crypto.spec.SecretKeySpec;/** * @author WHD */public class AesUtil {  private static final String AES="AES";  private static final String UTF8="UTF-8";  static KeyGenerator kgen =null;  static{    try {      kgen= KeyGenerator.getInstance(AES);    } catch (NoSuchAlgorithmException e) {      // TODO Auto-generated catch block      e.printStackTrace();    }  }  /*   * @param content:   * @param password:   */  private static byte[] encrypt(String content, String password) {    try {      // 使用静态代码块来生成KeyGenerator对象      //KeyGenerator kgen = KeyGenerator.getInstance(AES);      // 使用128 位      kgen.init(128, new SecureRandom(password.getBytes()));      SecretKey secretKey = kgen.generateKey();      byte[] encodeFormat = secretKey.getEncoded();      SecretKeySpec key = new SecretKeySpec(encodeFormat, AES);      // Cipher对象实际完成加密操作      Cipher cipher = Cipher.getInstance(AES);      // 加密内容进行编码      byte[] byteContent = content.getBytes(UTF8);      // 用密匙初始化Cipher对象      cipher.init(Cipher.ENCRYPT_MODE, key);      // 正式执行加密操作      byte[] result = cipher.doFinal(byteContent);      return result;    } catch (NoSuchAlgorithmException e) {      e.printStackTrace();    } catch (NoSuchPaddingException e) {      e.printStackTrace();    } catch (InvalidKeyException e) {      e.printStackTrace();    } catch (UnsupportedEncodingException e) {      e.printStackTrace();    } catch (IllegalBlockSizeException e) {      e.printStackTrace();    } catch (BadPaddingException e) {      e.printStackTrace();    }    return null;  }  /*   * @param content:   * @param password:   */  private static byte[] decrypt(byte[] content, String password) {    try {// 使用静态代码块来生成KeyGenerator对象      //KeyGenerator kgen = KeyGenerator.getInstance(AES);      // 使用128 位      kgen.init(128, new SecureRandom(password.getBytes()));      SecretKey secretKey = kgen.generateKey();      byte[] encodeFormat = secretKey.getEncoded();      SecretKeySpec key = new SecretKeySpec(encodeFormat, AES);      // Cipher对象实际完成加密操作      Cipher cipher = Cipher.getInstance(AES);      // 用密匙初始化Cipher对象      cipher.init(Cipher.DECRYPT_MODE, key);      // 正式执行解密操作      byte[] result = cipher.doFinal(content);      return result;    } catch (NoSuchAlgorithmException e) {      e.printStackTrace();    } catch (NoSuchPaddingException e) {      e.printStackTrace();    } catch (InvalidKeyException e) {      e.printStackTrace();    } catch (IllegalBlockSizeException e) {      e.printStackTrace();    } catch (BadPaddingException e) {      e.printStackTrace();    }    return null;  }  /**   * 二进制--》十六进制转化   * @param buf   * @return   */  private static String parseByte2HexStr(byte buf[]) {    StringBuffer sb = new StringBuffer();    for (int i = 0; i < buf.length; i++) {      String hex = Integer.toHexString(buf[i] & 0xFF);      if (hex.length() == 1) {        hex = '0' + hex;      }      sb.append(hex.toUpperCase());    }    return sb.toString();  }  /**   * 十六进制--》二进制转化   * @param hexStr   * @return   */  private static byte[] parseHexStr2Byte(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) throws UnsupportedEncodingException {    long begin=new Date().getTime();    String content = "aaades加密测试";    String password = "12345678dd";    // 加密    System.out.println("加密前：" + content);    byte[] encryptResult = encrypt(content, password);    String encryptResultStr = parseByte2HexStr(encryptResult);    System.out.println("加密后：" + encryptResultStr);    // 解密    byte[] decryptFrom = parseHexStr2Byte(encryptResultStr);    byte[] decryptResult = decrypt(decryptFrom, password);    // 解密内容进行解码    String result = new String(decryptResult, UTF8);    System.out.println("解密后：" + result);    long end= new Date().getTime();    System.out.println(end-begin);  }}