Java加密共通函数

import java.io.File;import java.io.IOException;import java.net.URL;import java.security.InvalidKeyException;import java.security.NoSuchAlgorithmException;import java.security.Security;import javax.crypto.BadPaddingException;import javax.crypto.Cipher;import javax.crypto.IllegalBlockSizeException;import javax.crypto.NoSuchPaddingException;import javax.crypto.spec.SecretKeySpec;import org.apache.commons.io.FileUtils;import org.apache.commons.lang.StringUtils;public class DesUtils {static {Security.addProvider(new com.sun.crypto.provider.SunJCE());}static boolean debug = true;private static String Algorithm = "AES";private static String secutiyKey = "1234567812345678";private static String fileName1="DESPW1.class";private static String fileName2="DESPW2.class";public static String getKey() throws Exception {String ret = "";URL url=DesUtils.class.getResource("");// 1.read the key from 1st fileret =new String(hex2byte(FileUtils.readFileToString(new File(url.getPath()+"/"+fileName1)))); // 2.read the key from 2nd file// 3.combine the keysret = ret + new String(hex2byte(FileUtils.readFileToString(new File(url.getPath()+"/"+fileName2)))); // 4.change them to the byte arrayreturn ret;}public static void writeKeyToFile(){String key=StringUtils.strip(secutiyKey);int lenght=key.length();String prefix="";String afterFix="";if(lenght>0){prefix=StringUtils.substring(key, 0, lenght/2);afterFix=StringUtils.substring(key, lenght/2+1, lenght);URL url=DesUtils.class.getResource("");try {FileUtils.writeStringToFile(new File(url.getPath()+"/"+fileName1), byte2hex(prefix.getBytes()));FileUtils.writeStringToFile(new File(url.getPath()+"/"+fileName2), byte2hex(afterFix.getBytes()));} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}}public static byte[] encodeConfig(byte[] set, byte[] key) {byte[] ret = null;// byte[] key = "tnts".getBytes();try {SecretKeySpec sk = new SecretKeySpec(key, Algorithm);Cipher c1;c1 = Cipher.getInstance(Algorithm);c1.init(Cipher.ENCRYPT_MODE, sk);ret = c1.doFinal(set);} catch (NoSuchAlgorithmException e) {e.printStackTrace();} catch (NoSuchPaddingException e) {e.printStackTrace();} catch (IllegalBlockSizeException e) {e.printStackTrace();} catch (BadPaddingException e) {e.printStackTrace();} catch (InvalidKeyException e) {e.printStackTrace();} catch (Exception e) {// TODO Auto-generated catch blocke.printStackTrace();}return ret;}public static byte[] decodeConfig(byte[] set, byte[] key) {byte[] ret = null;try {// byte[] key = getKey();SecretKeySpec sk = new SecretKeySpec(key, Algorithm);Cipher c1;c1 = Cipher.getInstance(Algorithm);c1.init(Cipher.DECRYPT_MODE, sk);ret = c1.doFinal(set);} catch (NoSuchAlgorithmException e) {e.printStackTrace();} catch (NoSuchPaddingException e) {e.printStackTrace();} catch (IllegalBlockSizeException e) {e.printStackTrace();} catch (BadPaddingException e) {e.printStackTrace();} catch (InvalidKeyException e) {e.printStackTrace();} catch (Exception e) {// TODO Auto-generated catch blocke.printStackTrace();}return ret;}// byte数组转换为16进制字符串public static String byte2hex(byte[] data) {StringBuffer sb = new StringBuffer();for (int i = 0; i < data.length; i++) {String temp = Integer.toHexString(((int) data[i]) & 0xFF);for (int t = temp.length(); t < 2; t++) {sb.append("0");}sb.append(temp);}return sb.toString();}// 16进制转换为byte数组public static byte[] hex2byte(String hexStr) {byte[] bts = new byte[hexStr.length() / 2];for (int i = 0, j = 0; j < bts.length; j++) {bts[j] = (byte) Integer.parseInt(hexStr.substring(i, i + 2), 16);i += 2;}return bts;}}