Java源码：

import java.security.Security; import javax.crypto.Cipher; import javax.crypto.SecretKey; import javax.crypto.spec.SecretKeySpec;  public class ThreeDES {  private static final String Algorithm = "DESede"; //定义 加密算法,可用 DES,DESede,Blowfish          //keybyte为加密密钥，长度为24字节     //src为被加密的数据缓冲区（源）     public static byte[] encryptMode(byte[] keybyte, byte[] src) {        try {             //生成密钥             SecretKey deskey = new SecretKeySpec(keybyte, Algorithm);              //加密             Cipher c1 = Cipher.getInstance(Algorithm);             c1.init(Cipher.ENCRYPT_MODE, deskey);             return c1.doFinal(src);         } catch (java.security.NoSuchAlgorithmException e1) {             e1.printStackTrace();         } catch (javax.crypto.NoSuchPaddingException e2) {             e2.printStackTrace();         } catch (java.lang.Exception e3) {             e3.printStackTrace();         }         return null;     }      //keybyte为加密密钥，长度为24字节     //src为加密后的缓冲区     public static byte[] decryptMode(byte[] keybyte, byte[] src) {           try {             //生成密钥             SecretKey deskey = new SecretKeySpec(keybyte, Algorithm);              //解密             Cipher c1 = Cipher.getInstance(Algorithm);             c1.init(Cipher.DECRYPT_MODE, deskey);             return c1.doFinal(src);         } catch (java.security.NoSuchAlgorithmException e1) {             e1.printStackTrace();         } catch (javax.crypto.NoSuchPaddingException e2) {             e2.printStackTrace();         } catch (java.lang.Exception e3) {             e3.printStackTrace();         }         return null;     }      //转换成十六进制字符串     public static String byte2hex(byte[] b) {         String hs="";         String stmp="";          for (int n=0;n<b.length;n++) {             stmp=(java.lang.Integer.toHexString(b[n] & 0XFF));             if (stmp.length()==1) hs=hs+"0"+stmp;             else hs=hs+stmp;             if (n<b.length-1)  hs=hs+":";         }         return hs.toUpperCase();     }          public static void main(String[] args)     {         //添加新安全算法,如果用JCE就要把它添加进去         Security.addProvider(new com.sun.crypto.provider.SunJCE());          final byte[] keyBytes = {0x11, 0x22, 0x4F, 0x58, (byte)0x88, 0x10, 0x40, 0x38                                , 0x28, 0x25, 0x79, 0x51, (byte)0xCB, (byte)0xDD, 0x55, 0x66                                , 0x77, 0x29, 0x74, (byte)0x98, 0x30, 0x40, 0x36, (byte)0xE2};    //24字节的密钥         String szSrc = "This is a 3DES test. 测试";                  System.out.println("加密前的字符串:" + szSrc);                  byte[] encoded = encryptMode(keyBytes, szSrc.getBytes());                 System.out.println("加密后的字符串:" + new String(encoded));                  byte[] srcBytes = decryptMode(keyBytes, encoded);         System.out.println("解密后的字符串:" + (new String(srcBytes)));     }  } 

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