java常用工具类之DES和Base64加密解密类

一、DES加密和解密

package com.itjh.javaUtil; import java.io.UnsupportedEncodingException; import java.security.InvalidKeyException; import java.security.NoSuchAlgorithmException; import java.security.SecureRandom; import java.security.spec.InvalidKeySpecException; 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.SecretKeyFactory; import javax.crypto.spec.DESKeySpec; /** * DES加密和解密。 * * @author 宋立君 * @date 2014年07月03日 */ public class DESUtil { /** 安全密钥 */ private String keyData = "ABCDEFGHIJKLMNOPQRSTWXYZabcdefghijklmnopqrstwxyz0123456789-_."; /** * 功能：构造 * * @author 宋立君 * @date 2014年07月03日 */ public DESUtil() { } /** * 功能：构造 * * @author 宋立君 * @date 2014年07月03日 * @param keyData * key */ public DESUtil(String key) { this.keyData = key; } /** * 功能：加密 (UTF-8) * * @author 宋立君 * @date 2014年07月03日 * @param source * 源字符串 * @param charSet * 编码 * @return String * @throws UnsupportedEncodingException * 编码异常 */ public String encrypt(String source) throws UnsupportedEncodingException { return encrypt(source, "UTF-8"); } /** * * 功能：解密 (UTF-8) * * @author 宋立君 * @date 2014年07月03日 * @param encryptedData * 被加密后的字符串 * @return String * @throws UnsupportedEncodingException * 编码异常 */ public String decrypt(String encryptedData) throws UnsupportedEncodingException { return decrypt(encryptedData, "UTF-8"); } /** * 功能：加密 * * @author 宋立君 * @date 2014年07月03日 * @param source * 源字符串 * @param charSet * 编码 * @return String * @throws UnsupportedEncodingException * 编码异常 */ public String encrypt(String source, String charSet) throws UnsupportedEncodingException { String encrypt = null; byte[] ret = encrypt(source.getBytes(charSet)); encrypt = new String(Base64.encode(ret)); return encrypt; } /** * * 功能：解密 * * @author 宋立君 * @date 2014年07月03日 * @param encryptedData * 被加密后的字符串 * @param charSet * 编码 * @return String * @throws UnsupportedEncodingException * 编码异常 */ public String decrypt(String encryptedData, String charSet) throws UnsupportedEncodingException { String descryptedData = null; byte[] ret = descrypt(Base64.decode(encryptedData.toCharArray())); descryptedData = new String(ret, charSet); return descryptedData; } /** * 加密数据用生成的密钥加密原始数据 * * @param primaryData * 原始数据 * @return byte[] * @author 宋立君 * @date 2014年07月03日 */ private byte[] encrypt(byte[] primaryData) { /** 取得安全密钥 */ byte rawKeyData[] = getKey(); /** DES算法要求有一个可信任的随机数源 */ SecureRandom sr = new SecureRandom(); /** 使用原始密钥数据创建DESKeySpec对象 */ DESKeySpec dks = null; try { dks = new DESKeySpec(keyData.getBytes()); } catch (InvalidKeyException e) { e.printStackTrace(); } /** 创建一个密钥工厂 */ SecretKeyFactory keyFactory = null; try { keyFactory = SecretKeyFactory.getInstance("DES"); } catch (NoSuchAlgorithmException e) { e.printStackTrace(); } /** 用密钥工厂把DESKeySpec转换成一个SecretKey对象 */ SecretKey key = null; try { key = keyFactory.generateSecret(dks); } catch (InvalidKeySpecException e) { e.printStackTrace(); } /** Cipher对象实际完成加密操作 */ Cipher cipher = null; try { cipher = Cipher.getInstance("DES"); } catch (NoSuchAlgorithmException e) { e.printStackTrace(); } catch (NoSuchPaddingException e) { e.printStackTrace(); } /** 用密钥初始化Cipher对象 */ try { cipher.init(Cipher.ENCRYPT_MODE, key, sr); } catch (InvalidKeyException e) { e.printStackTrace(); } /** 正式执行加密操作 */ byte encryptedData[] = null; try { encryptedData = cipher.doFinal(primaryData); } catch (IllegalStateException e) { e.printStackTrace(); } catch (IllegalBlockSizeException e) { e.printStackTrace(); } catch (BadPaddingException e) { e.printStackTrace(); } /** 返回加密数据 */ return encryptedData; } /** * 用密钥解密数据 * * @param encryptedData * 加密后的数据 * @return byte[] * @author 宋立君 * @date 2014年07月03日 */ private byte[] descrypt(byte[] encryptedData) { /** DES算法要求有一个可信任的随机数源 */ SecureRandom sr = new SecureRandom(); /** 取得安全密钥 */ byte rawKeyData[] = getKey(); /** 使用原始密钥数据创建DESKeySpec对象 */ DESKeySpec dks = null; try { dks = new DESKeySpec(keyData.getBytes()); } catch (InvalidKeyException e) { e.printStackTrace(); } /** 创建一个密钥工厂 */ SecretKeyFactory keyFactory = null; try { keyFactory = SecretKeyFactory.getInstance("DES"); } catch (NoSuchAlgorithmException e) { e.printStackTrace(); } /** 用密钥工厂把DESKeySpec转换成一个SecretKey对象 */ SecretKey key = null; try { key = keyFactory.generateSecret(dks); } catch (InvalidKeySpecException e) { e.printStackTrace(); } /** Cipher对象实际完成加密操作 */ Cipher cipher = null; try { cipher = Cipher.getInstance("DES"); } catch (NoSuchAlgorithmException e) { e.printStackTrace(); } catch (NoSuchPaddingException e) { e.printStackTrace(); } /** 用密钥初始化Cipher对象 */ try { cipher.init(Cipher.DECRYPT_MODE, key, sr); } catch (InvalidKeyException e) { e.printStackTrace(); } /** 正式执行解密操作 */ byte decryptedData[] = null; try { decryptedData = cipher.doFinal(encryptedData); } catch (IllegalStateException e) { e.printStackTrace(); } catch (IllegalBlockSizeException e) { e.printStackTrace(); } catch (BadPaddingException e) { e.printStackTrace(); } return decryptedData; } /** * 取得安全密钥此方法作废,因为每次key生成都不一样导致解密加密用的密钥都不一样，从而导致Given final block not * properly padded错误. * * @return byte数组 * @author 宋立君 * @date 2014年07月03日 */ private byte[] getKey() { /** DES算法要求有一个可信任的随机数源 */ SecureRandom sr = new SecureRandom(); /** 为我们选择的DES算法生成一个密钥生成器对象 */ KeyGenerator kg = null; try { kg = KeyGenerator.getInstance("DES"); } catch (NoSuchAlgorithmException e) { e.printStackTrace(); } kg.init(sr); /** 生成密钥工具类 */ SecretKey key = kg.generateKey(); /** 生成密钥byte数组 */ byte rawKeyData[] = key.getEncoded(); return rawKeyData; } }

二、Base64加密和解密

package com.itjh.javaUtil; import java.io.*; /** * Base64 编码和解码。 * * @author 宋立君 * @date 2014年07月03日 */ public class Base64 { public Base64() { } /** * 功能：编码字符串 * * @author 宋立君 * @date 2014年07月03日 * @param data * 源字符串 * @return String */ public static String encode(String data) { return new String(encode(data.getBytes())); } /** * 功能：解码字符串 * * @author 宋立君 * @date 2014年07月03日 * @param data * 源字符串 * @return String */ public static String decode(String data) { return new String(decode(data.toCharArray())); } /** * 功能：编码byte[] * * @author 宋立君 * @date 2014年07月03日 * @param data * 源 * @return char[] */ public static char[] encode(byte[] data) { char[] out = new char[((data.length + 2) / 3) * 4]; for (int i = 0, index = 0; i < data.length; i += 3, index += 4) { boolean quad = false; boolean trip = false; int val = (0xFF & (int) data[i]); val <<= 8; if ((i + 1) < data.length) { val |= (0xFF & (int) data[i + 1]); trip = true; } val <<= 8; if ((i + 2) < data.length) { val |= (0xFF & (int) data[i + 2]); quad = true; } out[index + 3] = alphabet[(quad ? (val & 0x3F) : 64)]; val >>= 6; out[index + 2] = alphabet[(trip ? (val & 0x3F) : 64)]; val >>= 6; out[index + 1] = alphabet[val & 0x3F]; val >>= 6; out[index + 0] = alphabet[val & 0x3F]; } return out; } /** * 功能：解码 * * @author 宋立君 * @date 2014年07月03日 * @param data * 编码后的字符数组 * @return byte[] */ public static byte[] decode(char[] data) { int tempLen = data.length; for (int ix = 0; ix < data.length; ix++) { if ((data[ix] > 255) || codes[data[ix]] < 0) { --tempLen; // ignore non-valid chars and padding } } // calculate required length: // -- 3 bytes for every 4 valid base64 chars // -- plus 2 bytes if there are 3 extra base64 chars, // or plus 1 byte if there are 2 extra. int len = (tempLen / 4) * 3; if ((tempLen % 4) == 3) { len += 2; } if ((tempLen % 4) == 2) { len += 1; } byte[] out = new byte[len]; int shift = 0; // # of excess bits stored in accum int accum = 0; // excess bits int index = 0; // we now go through the entire array (NOT using the 'tempLen' value) for (int ix = 0; ix < data.length; ix++) { int value = (data[ix] > 255) ? -1 : codes[data[ix]]; if (value >= 0) { // skip over non-code accum <<= 6; // bits shift up by 6 each time thru shift += 6; // loop, with new bits being put in accum |= value; // at the bottom. if (shift >= 8) { // whenever there are 8 or more shifted in, shift -= 8; // write them out (from the top, leaving any out[index++] = // excess at the bottom for next iteration. (byte) ((accum >> shift) & 0xff); } } } // if there is STILL something wrong we just have to throw up now! if (index != out.length) { throw new Error("Miscalculated data length (wrote " + index + " instead of " + out.length + ")"); } return out; } /** * 功能：编码文件 * * @author 宋立君 * @date 2014年07月03日 * @param file * 源文件 */ public static void encode(File file) throws IOException { if (!file.exists()) { System.exit(0); } else { byte[] decoded = readBytes(file); char[] encoded = encode(decoded); writeChars(file, encoded); } file = null; } /** * 功能：解码文件。 * * @author 宋立君 * @date 2014年07月03日 * @param file * 源文件 * @throws IOException */ public static void decode(File file) throws IOException { if (!file.exists()) { System.exit(0); } else { char[] encoded = readChars(file); byte[] decoded = decode(encoded); writeBytes(file, decoded); } file = null; } // // code characters for values 0..63 // private static char[] alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=" .toCharArray(); // // lookup table for converting base64 characters to value in range 0..63 // private static byte[] codes = new byte[256]; static { for (int i = 0; i < 256; i++) { codes[i] = -1; // LoggerUtil.debug(i + "&" + codes[i] + " "); } for (int i = 'A'; i <= 'Z'; i++) { codes[i] = (byte) (i - 'A'); // LoggerUtil.debug(i + "&" + codes[i] + " "); } for (int i = 'a'; i <= 'z'; i++) { codes[i] = (byte) (26 + i - 'a'); // LoggerUtil.debug(i + "&" + codes[i] + " "); } for (int i = '0'; i <= '9'; i++) { codes[i] = (byte) (52 + i - '0'); // LoggerUtil.debug(i + "&" + codes[i] + " "); } codes['+'] = 62; codes['/'] = 63; } private static byte[] readBytes(File file) throws IOException { ByteArrayOutputStream baos = new ByteArrayOutputStream(); byte[] b = null; InputStream fis = null; InputStream is = null; try { fis = new FileInputStream(file); is = new BufferedInputStream(fis); int count = 0; byte[] buf = new byte[16384]; while ((count = is.read(buf)) != -1) { if (count > 0) { baos.write(buf, 0, count); } } b = baos.toByteArray(); } finally { try { if (fis != null) fis.close(); if (is != null) is.close(); if (baos != null) baos.close(); } catch (Exception e) { System.out.println(e); } } return b; } private static char[] readChars(File file) throws IOException { CharArrayWriter caw = new CharArrayWriter(); Reader fr = null; Reader in = null; try { fr = new FileReader(file); in = new BufferedReader(fr); int count = 0; char[] buf = new char[16384]; while ((count = in.read(buf)) != -1) { if (count > 0) { caw.write(buf, 0, count); } } } finally { try { if (caw != null) caw.close(); if (in != null) in.close(); if (fr != null) fr.close(); } catch (Exception e) { System.out.println(e); } } return caw.toCharArray(); } private static void writeBytes(File file, byte[] data) throws IOException { OutputStream fos = null; OutputStream os = null; try { fos = new FileOutputStream(file); os = new BufferedOutputStream(fos); os.write(data); } finally { try { if (os != null) os.close(); if (fos != null) fos.close(); } catch (Exception e) { System.out.println(e); } } } private static void writeChars(File file, char[] data) throws IOException { Writer fos = null; Writer os = null; try { fos = new FileWriter(file); os = new BufferedWriter(fos); os.write(data); } finally { try { if (os != null) os.close(); if (fos != null) fos.close(); } catch (Exception e) { e.printStackTrace(); } } } // ///////////////////////////////////////////////// // end of test code. // ///////////////////////////////////////////////// }

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