本人想通過一個簡單加密和解密來對通訊的字符串進行安全監控。經過 一番的查找後,並對其進行了完整的整理。得出如下本人的代碼,該代碼經過了測試!
import java.security.Key;
import java.security.SecureRandom;
import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;
/**
*
* 使用DES加密與解密,可對byte[],String類型進行加密與解密
* 密文可使用String,byte[]存儲.
*
* 方法:
* void getKey(String strKey)從strKey的字條生成一個Key
*
* String getEncString(String strMing)對strMing進行加密,返回String密文
* String getDesString(String strMi)對strMin進行解密,返回String明文
*
* byte[] getEncCode(byte[] byteS)byte[]型的加密
* byte[] getDesCode(byte[] byteD)byte[]型的解密
*/
public class DesEncrypt
{
private static Key key;
/**
* 根據參數生成KEY
* @param strKey
*/
public static void getKey(String strKey){
try{
KeyGenerator _generator = KeyGenerator.getInstance("DES");
_generator.init(new SecureRandom(strKey.getBytes()));
key = _generator.generateKey();
_generator=null;
}catch(Exception e){
e.printStackTrace();
}
}
/**
* 加密String明文輸入,String密文輸出
* @param strMing
* @param key
* @return
*/
public static String getEncString(String strMing,String key){
byte[] byteMi = null;
byte[] byteMing = null;
String strMi = "";
BASE64Encoder base64en = new BASE64Encoder();
try {
getKey(key);
byteMing = strMing.getBytes("GB2312");
byteMi = getEncCode(byteMing);
strMi = base64en.encode(byteMi);
}catch(Exception e){
e.printStackTrace();
}finally {
base64en = null;
byteMing = null;
byteMi = null;
}
return strMi;
}
/**
* 解密 以String密文輸入,String明文輸出
* @param strMi
* @return
*/
public static String getDesString(String strMi,String key){
BASE64Decoder base64De = new BASE64Decoder();
byte[] byteMing = null;
byte[] byteMi = null;
String strMing = "";
try{
getKey(key);
byteMi = base64De.decodeBuffer(strMi);
byteMing = getDesCode(byteMi);
strMing = new String(byteMing,"GB2312");
}catch(Exception e){
e.printStackTrace();
}finally{
base64De = null;
byteMing = null;
byteMi = null;
}
return strMing;
}
/**
* 加密以byte[]明文輸入,byte[]密文輸出
* @param byteS
* @return
*/
private static byte[] getEncCode(byte[] byteS)
{
byte[] byteFina = null;
Cipher cipher;
try{
cipher = Cipher.getInstance("DES");
cipher.init(Cipher.ENCRYPT_MODE,key);
byteFina = cipher.doFinal(byteS);
}catch(Exception e){
e.printStackTrace();
}
finally
{
cipher = null;
}
return byteFina;
}
/**
* 解密以byte[]密文輸入,以byte[]明文輸出
* @param byteD
* @return
*/
private static byte[] getDesCode(byte[] byteD)
{
Cipher cipher;
byte[] byteFina=null;
try{
cipher = Cipher.getInstance("DES");
cipher.init(Cipher.DECRYPT_MODE, key);
byteFina = cipher.doFinal(byteD);
}catch(Exception e){
e.printStackTrace();
}finally{
cipher=null;
}
return byteFina;
}
public static void main(String args[]){
DesEncrypt des = new DesEncrypt();
String strEnc = des.getEncString("OKID","xxx");//加密字符串,返回String的密文
System.out.println(strEnc);
String strDes = des.getDesString(strEnc,"xxx");//把String 類型的密文解密
System.out.println(strDes);
}
}