Java tutorial
/* * Copyright 2013-2023 Peng Li <madding.lip@gmail.com> * Licensed under the AQNote License, Version 1.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.aqnote.com/licenses/LICENSE-1.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.aqnote.shared.encrypt.util; import static com.aqnote.shared.encrypt.util.log.LogAgg.*; import java.io.UnsupportedEncodingException; import java.security.InvalidKeyException; import java.security.NoSuchAlgorithmException; import java.security.spec.InvalidKeySpecException; import javax.crypto.BadPaddingException; import javax.crypto.Cipher; import javax.crypto.IllegalBlockSizeException; import javax.crypto.NoSuchPaddingException; import javax.crypto.SecretKey; import javax.crypto.SecretKeyFactory; import javax.crypto.spec.DESKeySpec; import org.apache.commons.codec.DecoderException; import org.apache.commons.codec.binary.Hex; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * DesEncrypt.java??DES/ * * @author madding.lip May 7, 2012 3:04:12 PM */ public class DesUtil { private static final Logger logger = LoggerFactory.getLogger(DesUtil.class); private static final String ALGORITHM = "DES"; private static final String ENCODE_UTF_8 = "UTF-8"; private static Cipher encodeCipher; private static Cipher decodeCipher; static { generateCipher("75229a3c9311d971fa7184d23b665670"); } public synchronized static byte[] encrypt(byte[] plaintext) { try { if (plaintext == null) { return null; } return encodeCipher.doFinal(plaintext); } catch (IllegalStateException e) { throw new RuntimeException(e); } catch (IllegalBlockSizeException e) { throw new RuntimeException(e); } catch (BadPaddingException e) { throw new RuntimeException(e); } } public synchronized static String encrypt(String plaintext) { String result = null; try { if (plaintext == null) { return null; } result = new String(Hex.encodeHex(encodeCipher.doFinal(plaintext.getBytes(ENCODE_UTF_8)))); } catch (IllegalStateException e) { logger.error(MSG(R.F, "encrypt", plaintext, e.getMessage()), e); } catch (IllegalBlockSizeException e) { logger.error(MSG(R.F, "encrypt", plaintext, e.getMessage()), e); } catch (BadPaddingException e) { logger.error(MSG(R.F, "encrypt", plaintext, e.getMessage()), e); } catch (UnsupportedEncodingException e) { logger.error(MSG(R.F, "encrypt", plaintext, e.getMessage()), e); } finally { } return result; } public synchronized static byte[] decrypt(byte[] cryptotext) { try { if (cryptotext == null) { return null; } return decodeCipher.doFinal(cryptotext); } catch (IllegalStateException e) { throw new RuntimeException(e); } catch (IllegalBlockSizeException e) { throw new RuntimeException(e); } catch (BadPaddingException e) { throw new RuntimeException(e); } } public synchronized static String decrypt(String cryptotext) { String result = null; try { byte[] clearByte; if (cryptotext == null) { return null; } clearByte = decodeCipher.doFinal(Hex.decodeHex(cryptotext.toCharArray())); result = new String(clearByte, ENCODE_UTF_8); } catch (IllegalStateException e) { logger.error(MSG(R.F, "decrypt", cryptotext, e.getMessage()), e); } catch (IllegalBlockSizeException e) { logger.error(MSG(R.F, "decrypt", cryptotext, e.getMessage()), e); } catch (BadPaddingException e) { logger.error(MSG(R.F, "decrypt", cryptotext, e.getMessage()), e); } catch (UnsupportedEncodingException e) { logger.error(MSG(R.F, "decrypt", cryptotext, e.getMessage()), e); } catch (DecoderException e) { logger.error(MSG(R.F, "decrypt", cryptotext, e.getMessage()), e); } finally { } return result; } // ??? private static void generateCipher(String rawKey) { try { DESKeySpec dks = new DESKeySpec(rawKey.getBytes()); SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(ALGORITHM); SecretKey deskey = keyFactory.generateSecret(dks); encodeCipher = Cipher.getInstance(ALGORITHM); encodeCipher.init(Cipher.ENCRYPT_MODE, deskey); decodeCipher = Cipher.getInstance(ALGORITHM); decodeCipher.init(Cipher.DECRYPT_MODE, deskey); } catch (InvalidKeyException e) { throw new RuntimeException(e); } catch (NoSuchAlgorithmException e) { throw new RuntimeException(e); } catch (InvalidKeySpecException e) { throw new RuntimeException(e); } catch (NoSuchPaddingException e) { throw new RuntimeException(e); } } }