DES加密

DES加密文件和字符串

/* * @(#)DESUtil.java Jan 7, 2013 * * @Company < Technology Development Company LTD..> */package com.des;import java.io.FileInputStream;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStream;import java.io.ObjectInput;import java.io.ObjectInputStream;import java.io.ObjectOutput;import java.io.ObjectOutputStream;import java.io.OutputStream;import java.security.InvalidKeyException;import java.security.Key;import java.security.NoSuchAlgorithmException;import java.security.SecureRandom;import javax.crypto.BadPaddingException;import javax.crypto.Cipher;import javax.crypto.CipherInputStream;import javax.crypto.CipherOutputStream;import javax.crypto.IllegalBlockSizeException;import javax.crypto.KeyGenerator;import javax.crypto.NoSuchPaddingException;/** * @Project <CL-Allocation tool> * @version <1.0> * @Author  <Administrator> * @Date    <Jan 7, 2013> * @description  */public class DESUtil {private Key key = null;public DESUtil(){}public DESUtil(String strKey){setKey(strKey);}/**根据参数生成一个密室* @param strKey*/public void setKey(String strKey){OutputStream os = null;ObjectOutput objectOut = null;try {KeyGenerator keyGenerator = KeyGenerator.getInstance("DES");keyGenerator.init(new SecureRandom(strKey.getBytes()));key = keyGenerator.generateKey();//密室写入文件保存os = new FileOutputStream("E:\\key.key");objectOut = new ObjectOutputStream(os);objectOut.writeObject(key);} catch (NoSuchAlgorithmException e) {e.printStackTrace();throw new RuntimeException("Error initializing SqlMap class. Cause: " + e);} catch (FileNotFoundException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}finally{try {if(objectOut!=null){objectOut.close();}} catch (IOException e) {e.printStackTrace();}try {if(os!=null){os.close();}} catch (IOException e) {e.printStackTrace();}}}/*** 读取密室*/public void getKey(){InputStream  is = null;ObjectInput objectIn = null;try {is = new FileInputStream("E:\\key.key");objectIn = new ObjectInputStream(is);key = (Key) objectIn.readObject();} catch (FileNotFoundException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();} catch (ClassNotFoundException e) {e.printStackTrace();}finally{try {if(objectIn!=null){objectIn.close();}} catch (IOException e) {e.printStackTrace();}try {if(is!=null){is.close();}} catch (IOException e) {e.printStackTrace();}}}/**加密，明文输入，密文输出* @param strMing* @return*/public String encryptStr(String strMing){byte[] byteMi = null;byte[] byteMing = null;String strMi = "";try {byteMing = strMing.getBytes("UTF-8");byteMi = this.encryptByte(byteMing);strMi = Base64.encode(byteMi);} catch (Exception e) {e.printStackTrace();}return strMi;}/**解密，密文输入，明文输出* @param strMi* @return*/public String decryptStr(String strMi){String strMing = "";byte[] byteMi = null;byte[] byteMing = null;try {byteMi = Base64.decode(strMi);byteMing = this.decryptByte(byteMi);strMing = new String(byteMing,"UTF-8");} catch (Exception e) {e.printStackTrace();}return strMing;}/**      * 解密以 byte[] 密文输入 , 以 byte[] 明文输出      *      * @param byteD      * @return      */  private byte[] decryptByte(byte[] bytes){Cipher cipher = null;byte[] byteFina = null;try {cipher = Cipher.getInstance("DES");cipher.init(Cipher.DECRYPT_MODE, key);byteFina = cipher.doFinal(bytes);} 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();}finally{  cipher = null ;  }return byteFina;}/**      * 加密以 byte[] 明文输入 ,byte[] 密文输出      *      * @param byteS      * @return      */  private byte[] encryptByte(byte[] bytes){byte[] byteFina = null;Cipher cipher = null;try {cipher = Cipher.getInstance("DES");cipher.init(Cipher.ENCRYPT_MODE, key);byteFina = cipher.doFinal(bytes);} 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();}finally{  cipher = null ;  }return byteFina;}/**      * 文件 file 进行加密并保存目标文件 destFile 中      *      * @param file      *             要加密的文件 如 c:/test/srcFile.txt      * @param destFile      *             加密后存放的文件名 如 c:/ 加密后文件 .txt      */ public void encryptFile(String filePath,String destPath){Cipher cipher = null;InputStream is = null;OutputStream os = null;InputStream cis = null;try {cipher = Cipher.getInstance("DES");cipher.init(Cipher.ENCRYPT_MODE, key);is = new FileInputStream(filePath);os  = new FileOutputStream(destPath);cis = new CipherInputStream(is,cipher);byte[] buffer = new byte[1024];int len = 0;while((len=cis.read(buffer))>=0){os.write(buffer, 0,len);}} catch (NoSuchAlgorithmException e) {e.printStackTrace();} catch (NoSuchPaddingException e) {e.printStackTrace();} catch (InvalidKeyException e) {e.printStackTrace();} catch (FileNotFoundException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}finally{cipher = null;try {if(cis!=null){cis.close();}} catch (Exception e) {e.printStackTrace();}try {if(os!=null){os.close();}} catch (IOException e) {e.printStackTrace();}try {if(is!=null){is.close();}} catch (IOException e) {e.printStackTrace();}}}  /**      * 文件采用 DES 算法解密文件      *      * @param file      *             已加密的文件 如 c:/ 加密后文件 .txt *      * @param destFile      *             解密后存放的文件名 如 c:/ test/ 解密后文件 .txt      */  public void decryptFile(String filePath,String destPath){Cipher cipher = null;InputStream is = null;OutputStream os = null;CipherOutputStream cos = null;try {is = new FileInputStream(filePath);os = new FileOutputStream(destPath);cipher = Cipher.getInstance("DES");cipher.init(Cipher.DECRYPT_MODE, key);cos = new CipherOutputStream(os,cipher);int len = 0;byte[] buffer = new byte[1024];while((len=is.read(buffer))>=0){cos.write(buffer, 0, len);}} catch (FileNotFoundException e) {e.printStackTrace();} catch (NoSuchAlgorithmException e) {e.printStackTrace();} catch (NoSuchPaddingException e) {e.printStackTrace();} catch (InvalidKeyException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}finally{cipher = null;try {if(cos!=null){cos.close();}} catch (Exception e) {e.printStackTrace();}try {if(os!=null){os.close();}} catch (IOException e) {e.printStackTrace();}try {if(is!=null){is.close();}} catch (IOException e) {e.printStackTrace();}}}}

测试方法

public static void main(String[] args) {DESUtil des = new DESUtil("1234567");des.getKey();String strMi = des.encryptStr("des加密的文件sss德萨发家史凯夫拉激发放假");System.out.println(strMi);strMi = des.decryptStr(strMi);}