字符数据如何用DES加密

在Java中使用DES加密算法对字符数据进行加密，具体方法如下：

public class DesTool {
private static final String PASSKEY = "afasdf";
private static final String DESKEY = "asfsdfsdf";
public static String encoderOrdecoder( String src, int mode) {
String tag="";
InputStream is = null;
OutputStream out = null;
CipherInputStream cis = null;
try {
SecureRandom sr = new SecureRandom();
DESKeySpec dks = new DESKeySpec(DESKEY.getBytes());
SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
SecretKey securekey = keyFactory.generateSecret(dks);
IvParameterSpec iv = new IvParameterSpec(PASSKEY.getBytes());
Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
cipher.init(mode, securekey, iv, sr);
cis = new CipherInputStream(new ByteArrayInputStream(src.getBytes()) , cipher);
out=new ByteArrayOutputStream();
byte[] buffer = new byte[1024];
int r;
while ((r = cis.read(buffer)) > 0) {
out.write(buffer, 0, r);
}
tag=out.toString();
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if (is != null) {
is.close();
}
if (cis != null) {
cis.close();
}
if (out != null) {
out.close();
}
} catch (Exception e1){
}
}
return tag;
}
public static void main(String[] args) {
System.out.println("aaa"); 
String t=encoderOrdecoder("aaa", Cipher.ENCRYPT_MODE );
System.out.println(t); 
System.out.println(encoderOrdecoder(t, Cipher.DECRYPT_MODE ));
}
}