密钥最低128bits
public class FileEncryptionUtil {private static final String ALGORITHM = "AES";private static final String TRANSFORMATION = "AES";/*** 使用AES加密算法对文件进行加密。** @param key        用于加密的密钥。.* @param inputFiles  要加密的输入文件。* @param outputFiles 将写入加密数据的输出文件。* @throws Exception 如果加密过程中出现错误*/public static void encryptFile(String key, String inputFiles, String outputFiles) throws Exception {File inputFile = new File(inputFiles);File outputFile = new File(outputFiles);Key secretKey = new SecretKeySpec(key.getBytes("UTF-8"), ALGORITHM);Cipher cipher = Cipher.getInstance(TRANSFORMATION);cipher.init(Cipher.ENCRYPT_MODE, secretKey);FileInputStream inputStream = new FileInputStream(inputFile);byte[] inputBytes = new byte[(int) inputFile.length()];inputStream.read(inputBytes);byte[] outputBytes = cipher.doFinal(inputBytes);FileOutputStream outputStream = new FileOutputStream(outputFile);outputStream.write(outputBytes);inputStream.close();outputStream.close();}/*** 解密使用AES加密算法加密的文件。** @param key        用于解密的密钥。* @param inputFiles  要解密的输入文件。* @param outputFiles 将写入解密数据的输出文件* @throws Exception 如果在解密过程中出现错误。*/public static void decryptFile(String key, String inputFiles, String outputFiles) throws Exception {File inputFile = new File(inputFiles);File outputFile = new File(outputFiles);Key secretKey = new SecretKeySpec(key.getBytes("UTF-8"), ALGORITHM);Cipher cipher = Cipher.getInstance(TRANSFORMATION);cipher.init(Cipher.DECRYPT_MODE, secretKey);FileInputStream inputStream = new FileInputStream(inputFile);byte[] inputBytes = new byte[(int) inputFile.length()];inputStream.read(inputBytes);byte[] outputBytes = cipher.doFinal(inputBytes);FileOutputStream outputStream = new FileOutputStream(outputFile);outputStream.write(outputBytes);inputStream.close();outputStream.close();}
}