des加密java實現

A. DES加密演算法 java實現

package des;

import java.io.*;
import java.nio.*;
import java.nio.channels.FileChannel;

public class FileDES{
private static final boolean enc=true; //加密
private static final boolean dec=false; //解密

private String srcFileName;
private String destFileName;
private String inKey;
private boolean actionType;
private File srcFile;
private File destFile;
private Des des;

private void analyzePath(){
String dirName;
int pos=srcFileName.lastIndexOf("/");
dirName=srcFileName.substring(0,pos);
File dir=new File(dirName);
if (!dir.exists()){
System.err.println(dirName+" is not exist");
System.exit(1);
}else if(!dir.isDirectory()){
System.err.println(dirName+" is not a directory");
System.exit(1);
}

pos=destFileName.lastIndexOf("/");
dirName=destFileName.substring(0,pos);
dir=new File(dirName);
if (!dir.exists()){
if(!dir.mkdirs()){
System.out.println ("can not creat directory:"+dirName);
System.exit(1);
}
}else if(!dir.isDirectory()){
System.err.println(dirName+" is not a directory");
System.exit(1);
}
}

private static int replenish(FileChannel channel,ByteBuffer buf) throws IOException{
long byteLeft=channel.size()-channel.position();
if(byteLeft==0L)
return -1;
buf.position(0);
buf.limit(buf.position()+(byteLeft<8 ? (int)byteLeft :8));
return channel.read(buf);
}

private void file_operate(boolean flag){
des=new Des(inKey);
FileOutputStream outputFile=null;
try {
outputFile=new FileOutputStream(srcFile,true);
}catch (java.io.FileNotFoundException e) {
e.printStackTrace(System.err);
}
FileChannel outChannel=outputFile.getChannel();

try{
if(outChannel.size()%2!=0){
ByteBuffer bufTemp=ByteBuffer.allocate(1);
bufTemp.put((byte)32);
bufTemp.flip();
outChannel.position(outChannel.size());
outChannel.write(bufTemp);
bufTemp.clear();
}
}catch(Exception ex){
ex.printStackTrace(System.err);
System.exit(1);
}
FileInputStream inFile=null;
try{
inFile=new FileInputStream(srcFile);
}catch(java.io.FileNotFoundException e){
e.printStackTrace(System.err);
//System.exit(1);
}
outputFile=null;
try {
outputFile=new FileOutputStream(destFile,true);
}catch (java.io.FileNotFoundException e) {
e.printStackTrace(System.err);
}

FileChannel inChannel=inFile.getChannel();
outChannel=outputFile.getChannel();

ByteBuffer inBuf=ByteBuffer.allocate(8);
ByteBuffer outBuf=ByteBuffer.allocate(8);

try{
String srcStr;
String destStr;
while(true){

if (replenish(inChannel,inBuf)==-1) break;
srcStr=((ByteBuffer)(inBuf.flip())).asCharBuffer().toString();
inBuf.clear();
if (flag)
destStr=des.enc(srcStr,srcStr.length());
else
destStr=des.dec(srcStr,srcStr.length());
outBuf.clear();
if (destStr.length()==4){
for (int i = 0; i<4; i++) {
outBuf.putChar(destStr.charAt(i));
}
outBuf.flip();
}else{
outBuf.position(0);
outBuf.limit(2*destStr.length());
for (int i = 0; i<destStr.length(); i++) {
outBuf.putChar(destStr.charAt(i));
}
outBuf.flip();
}

try {
outChannel.write(outBuf);
outBuf.clear();
}catch (java.io.IOException ex) {
ex.printStackTrace(System.err);
}
}
System.out.println (inChannel.size());
System.out.println (outChannel.size());
System.out.println ("EoF reached.");
inFile.close();
outputFile.close();
}catch(java.io.IOException e){
e.printStackTrace(System.err);
System.exit(1);
}
}

public FileDES(String srcFileName,String destFileName,String inKey,boolean actionType){
this.srcFileName=srcFileName;
this.destFileName=destFileName;
this.actionType=actionType;
analyzePath();
srcFile=new File(srcFileName);
destFile=new File(destFileName);
this.inKey=inKey;
if (actionType==enc)
file_operate(enc);
else
file_operate(dec);
}

public static void main(String[] args){
String file1=System.getProperty("user.dir")+"/111.doc";
String file2=System.getProperty("user.dir")+"/222.doc";
String file3=System.getProperty("user.dir")+"/333.doc";
String passWord="1234ABCD";
FileDES fileDes=new FileDES(file1,file2,passWord,true);
FileDES fileDes1=new FileDES(file2,file3,passWord,false);
}

B. 用java實現DES加密演算法，細致點，要直接粘貼進平台能運行的！！

/*des密鑰生成代碼*/
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.security.spec.InvalidKeySpecException;

import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;

import com.huateng.util.common.Log;

public class GenKey {

private static final String DES = "DES";
public static final String SKEY_NAME = "key.des";

public static void genKey1(String path) {

// 密鑰
SecretKey skey = null;
// 密鑰隨機數生成
SecureRandom sr = new SecureRandom();
//生成密鑰文件
File file = genFile(path);

try {
// 獲取密鑰生成實例
KeyGenerator gen = KeyGenerator.getInstance(DES);
// 初始化密鑰生成器
gen.init(sr);
// 生成密鑰
skey = gen.generateKey();
// System.out.println(skey);

ObjectOutputStream oos = new ObjectOutputStream(
new FileOutputStream(file));
oos.writeObject(skey);
oos.close();
Log.sKeyPath(path);
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}

/**
* @param file ： 生成密鑰的路徑
* SecretKeyFactory 方式生成des密鑰
* */
public static void genKey2(String path) {
// 密鑰隨機數生成
SecureRandom sr = new SecureRandom();
// byte[] bytes = {11,12,44,99,76,45,1,8};
byte[] bytes = sr.generateSeed(20);
// 密鑰
SecretKey skey = null;
//生成密鑰文件路徑
File file = genFile(path);

try {
//創建deskeyspec對象
DESKeySpec desKeySpec = new DESKeySpec(bytes,9);
//實例化des密鑰工廠
SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DES);
//生成密鑰對象
skey = keyFactory.generateSecret(desKeySpec);
//寫出密鑰對象
ObjectOutputStream oos = new ObjectOutputStream(
new FileOutputStream(file));
oos.writeObject(skey);
oos.close();
Log.sKeyPath(path);
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
} catch (InvalidKeyException e) {
e.printStackTrace();
} catch (InvalidKeySpecException e) {
e.printStackTrace();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}

}

private static File genFile(String path) {
String temp = null;
File newFile = null;
if (path.endsWith("/") || path.endsWith("\\")) {
temp = path;
} else {
temp = path + "/";
}

File pathFile = new File(temp);
if (!pathFile.exists())
pathFile.mkdirs();

newFile = new File(temp+SKEY_NAME);

return newFile;
}
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
genKey2("E:/a/aa/");
}

}
/*加解密*/
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;

import javax.crypto.Cipher;
import javax.crypto.CipherInputStream;
import javax.crypto.SecretKey;
public class SecUtil {
public static void decrypt(String keyPath, String source, String dest) {
SecretKey key = null;
try

{
ObjectInputStream keyFile = new ObjectInputStream(
//讀取加密密鑰
new FileInputStream(keyPath));
key = (SecretKey) keyFile.readObject();
keyFile.close();
}
catch (FileNotFoundException ey1) {

throw new RuntimeException(ey1);
}
catch (Exception ey2) {
throw new RuntimeException(ey2);
}
//用key產生Cipher
Cipher cipher = null;
try {
//設置演算法,應該與加密時的設置一樣
cipher = Cipher.getInstance("DES");
//設置解密模式
cipher.init(Cipher.DECRYPT_MODE, key);
}
catch (Exception ey3) {
throw new RuntimeException(ey3);
}
//取得要解密的文件並解密
File file = new File(source);
String filename = file.getName();
try {
//輸出流,請注意文件名稱的獲取
BufferedOutputStream out = new BufferedOutputStream(new FileOutputStream(dest));
//輸入流
CipherInputStream in = new CipherInputStream(new BufferedInputStream(
new FileInputStream(file)), cipher);
int thebyte = 0;
while ( (thebyte = in.read()) != -1) {
out.write(thebyte);
}
in.close();
out.close();
}
catch (Exception ey5) {
throw new RuntimeException(ey5);
}
}

public static void encrypt(String keyPath, String source, String dest) {
SecretKey key = null;
try

{
ObjectInputStream keyFile = new ObjectInputStream(
//讀取加密密鑰
new FileInputStream(keyPath));
key = (SecretKey) keyFile.readObject();
keyFile.close();
}
catch (FileNotFoundException ey1) {
throw new RuntimeException(ey1);
}
catch (Exception ey2) {
throw new RuntimeException(ey2);
}
//用key產生Cipher
Cipher cipher = null;
try {
//設置演算法,應該與加密時的設置一樣
cipher = Cipher.getInstance("DES");
//設置解密模式
cipher.init(Cipher.ENCRYPT_MODE, key);
}
catch (Exception ey3) {
throw new RuntimeException(ey3);
}
//取得要解密的文件並解密
File file = new File(source);
String filename = file.getName();
try {
//輸出流,請注意文件名稱的獲取
BufferedOutputStream out = new BufferedOutputStream(new FileOutputStream(dest));
//輸入流
CipherInputStream in = new CipherInputStream(new BufferedInputStream(
new FileInputStream(file)), cipher);
int thebyte = 0;
while ( (thebyte = in.read()) != -1) {
out.write(thebyte);
}
in.close();
out.close();
}
catch (Exception ey5) {
throw new RuntimeException(ey5);
}
}
}

C. 如何用JAVA實現字元串簡單加密解密

java加密字元串可以使用des加密演算法，實例如下：
package test;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.security.*;
import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
/**
* 加密解密
*
* @author shy.qiu
* @since
*/
public class CryptTest {
/**
* 進行MD5加密
*
* @param info
* 要加密的信息
* @return String 加密後的字元串
*/
public String encryptToMD5(String info) {
byte[] digesta = null;
try {
// 得到一個md5的消息摘要
MessageDigest alga = MessageDigest.getInstance("MD5");
// 添加要進行計算摘要的信息
alga.update(info.getBytes());
// 得到該摘要
digesta = alga.digest();
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
// 將摘要轉為字元串
String rs = byte2hex(digesta);
return rs;
}
/**
* 進行SHA加密
*
* @param info
* 要加密的信息
* @return String 加密後的字元串
*/
public String encryptToSHA(String info) {
byte[] digesta = null;
try {
// 得到一個SHA-1的消息摘要
MessageDigest alga = MessageDigest.getInstance("SHA-1");
// 添加要進行計算摘要的信息
alga.update(info.getBytes());
// 得到該摘要
digesta = alga.digest();
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
// 將摘要轉為字元串
String rs = byte2hex(digesta);
return rs;
}
// //////////////////////////////////////////////////////////////////////////
/**
* 創建密匙
*
* @param algorithm
* 加密演算法,可用 DES,DESede,Blowfish
* @return SecretKey 秘密（對稱）密鑰
*/
public SecretKey createSecretKey(String algorithm) {
// 聲明KeyGenerator對象
KeyGenerator keygen;
// 聲明 密鑰對象
SecretKey deskey = null;
try {
// 返回生成指定演算法的秘密密鑰的 KeyGenerator 對象
keygen = KeyGenerator.getInstance(algorithm);
// 生成一個密鑰
deskey = keygen.generateKey();
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
// 返回密匙
return deskey;
}
/**
* 根據密匙進行DES加密
*
* @param key
* 密匙
* @param info
* 要加密的信息
* @return String 加密後的信息
*/
public String encryptToDES(SecretKey key, String info) {
// 定義 加密演算法,可用 DES,DESede,Blowfish
String Algorithm = "DES";
// 加密隨機數生成器 (RNG),(可以不寫)
SecureRandom sr = new SecureRandom();
// 定義要生成的密文
byte[] cipherByte = null;
try {
// 得到加密/解密器
Cipher c1 = Cipher.getInstance(Algorithm);
// 用指定的密鑰和模式初始化Cipher對象
// 參數:(ENCRYPT_MODE, DECRYPT_MODE, WRAP_MODE,UNWRAP_MODE)
c1.init(Cipher.ENCRYPT_MODE, key, sr);
// 對要加密的內容進行編碼處理,
cipherByte = c1.doFinal(info.getBytes());
} catch (Exception e) {
e.printStackTrace();
}
// 返回密文的十六進制形式
return byte2hex(cipherByte);
}
/**
* 根據密匙進行DES解密
*
* @param key
* 密匙
* @param sInfo
* 要解密的密文
* @return String 返回解密後信息
*/
public String decryptByDES(SecretKey key, String sInfo) {
// 定義 加密演算法,
String Algorithm = "DES";
// 加密隨機數生成器 (RNG)
SecureRandom sr = new SecureRandom();
byte[] cipherByte = null;
try {
// 得到加密/解密器
Cipher c1 = Cipher.getInstance(Algorithm);
// 用指定的密鑰和模式初始化Cipher對象
c1.init(Cipher.DECRYPT_MODE, key, sr);
// 對要解密的內容進行編碼處理
cipherByte = c1.doFinal(hex2byte(sInfo));
} catch (Exception e) {
e.printStackTrace();
}
// return byte2hex(cipherByte);
return new String(cipherByte);
}
// /////////////////////////////////////////////////////////////////////////////
/**
* 創建密匙組，並將公匙，私匙放入到指定文件中
*
* 默認放入mykeys.bat文件中
*/
public void createPairKey() {
try {
// 根據特定的演算法一個密鑰對生成器
KeyPairGenerator keygen = KeyPairGenerator.getInstance("DSA");
// 加密隨機數生成器 (RNG)
SecureRandom random = new SecureRandom();
// 重新設置此隨機對象的種子
random.setSeed(1000);
// 使用給定的隨機源（和默認的參數集合）初始化確定密鑰大小的密鑰對生成器
keygen.initialize(512, random);// keygen.initialize(512);
// 生成密鑰組
KeyPair keys = keygen.generateKeyPair();
// 得到公匙
PublicKey pubkey = keys.getPublic();
// 得到私匙
PrivateKey prikey = keys.getPrivate();
// 將公匙私匙寫入到文件當中
doObjToFile("mykeys.bat", new Object[] { prikey, pubkey });
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
}
/**
* 利用私匙對信息進行簽名 把簽名後的信息放入到指定的文件中
*
* @param info
* 要簽名的信息
* @param signfile
* 存入的文件
*/
public void signToInfo(String info, String signfile) {
// 從文件當中讀取私匙
PrivateKey myprikey = (PrivateKey) getObjFromFile("mykeys.bat", 1);
// 從文件中讀取公匙
PublicKey mypubkey = (PublicKey) getObjFromFile("mykeys.bat", 2);
try {
// Signature 對象可用來生成和驗證數字簽名
Signature signet = Signature.getInstance("DSA");
// 初始化簽署簽名的私鑰
signet.initSign(myprikey);
// 更新要由位元組簽名或驗證的數據
signet.update(info.getBytes());
// 簽署或驗證所有更新位元組的簽名，返回簽名
byte[] signed = signet.sign();
// 將數字簽名,公匙,信息放入文件中
doObjToFile(signfile, new Object[] { signed, mypubkey, info });
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* 讀取數字簽名文件 根據公匙，簽名，信息驗證信息的合法性
*
* @return true 驗證成功 false 驗證失敗
*/
public boolean validateSign(String signfile) {
// 讀取公匙
PublicKey mypubkey = (PublicKey) getObjFromFile(signfile, 2);
// 讀取簽名
byte[] signed = (byte[]) getObjFromFile(signfile, 1);
// 讀取信息
String info = (String) getObjFromFile(signfile, 3);
try {
// 初始一個Signature對象,並用公鑰和簽名進行驗證
Signature signetcheck = Signature.getInstance("DSA");
// 初始化驗證簽名的公鑰
signetcheck.initVerify(mypubkey);
// 使用指定的 byte 數組更新要簽名或驗證的數據
signetcheck.update(info.getBytes());
System.out.println(info);
// 驗證傳入的簽名
return signetcheck.verify(signed);
} catch (Exception e) {
e.printStackTrace();
return false;
}
}
/**
* 將二進制轉化為16進制字元串
*
* @param b
* 二進制位元組數組
* @return String
*/
public 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;
}
}
return hs.toUpperCase();
}
/**
* 十六進制字元串轉化為2進制
*
* @param hex
* @return
*/
public byte[] hex2byte(String hex) {
byte[] ret = new byte[8];
byte[] tmp = hex.getBytes();
for (int i = 0; i < 8; i++) {
ret[i] = uniteBytes(tmp[i * 2], tmp[i * 2 + 1]);
}
return ret;
}
/**
* 將兩個ASCII字元合成一個位元組； 如："EF"--> 0xEF
*
* @param src0
* byte
* @param src1
* byte
* @return byte
*/
public static byte uniteBytes(byte src0, byte src1) {
byte _b0 = Byte.decode("0x" + new String(new byte[] { src0 }))
.byteValue();
_b0 = (byte) (_b0 << 4);
byte _b1 = Byte.decode("0x" + new String(new byte[] { src1 }))
.byteValue();
byte ret = (byte) (_b0 ^ _b1);
return ret;
}
/**
* 將指定的對象寫入指定的文件
*
* @param file
* 指定寫入的文件
* @param objs
* 要寫入的對象
*/
public void doObjToFile(String file, Object[] objs) {
ObjectOutputStream oos = null;
try {
FileOutputStream fos = new FileOutputStream(file);
oos = new ObjectOutputStream(fos);
for (int i = 0; i < objs.length; i++) {
oos.writeObject(objs[i]);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
oos.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**
* 返回在文件中指定位置的對象
*
* @param file
* 指定的文件
* @param i
* 從1開始
* @return
*/
public Object getObjFromFile(String file, int i) {
ObjectInputStream ois = null;
Object obj = null;
try {
FileInputStream fis = new FileInputStream(file);
ois = new ObjectInputStream(fis);
for (int j = 0; j < i; j++) {
obj = ois.readObject();
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
ois.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return obj;
}
/**
* 測試
*
* @param args
*/
public static void main(String[] args) {
CryptTest jiami = new CryptTest();
// 執行MD5加密"Hello world!"
System.out.println("Hello經過MD5:" + jiami.encryptToMD5("Hello"));
// 生成一個DES演算法的密匙
SecretKey key = jiami.createSecretKey("DES");
// 用密匙加密信息"Hello world!"
String str1 = jiami.encryptToDES(key, "Hello");
System.out.println("使用des加密信息Hello為:" + str1);
// 使用這個密匙解密
String str2 = jiami.decryptByDES(key, str1);
System.out.println("解密後為：" + str2);
// 創建公匙和私匙
jiami.createPairKey();
// 對Hello world!使用私匙進行簽名
jiami.signToInfo("Hello", "mysign.bat");
// 利用公匙對簽名進行驗證。
if (jiami.validateSign("mysign.bat")) {
System.out.println("Success!");
} else {
System.out.println("Fail!");
}
}
}

D. JAVA對DES加密解密的實現

呃，貌似DES加密解密的時候可以不用尼個generatekey（）方法的，比如說下面的代碼

Cipher c = Cipher.getInstance("DES");
SecretKeySpec sk=new SecretKeySpec("00000000".getBytes(),"DES");
c.init(Cipher.ENCRYPT_MODE,sk);

byte encode[]=c.doFinal("0123456789".getBytes());
for(byte b:encode)System.out.print(b+",");

c.init(Cipher.DECRYPT_MODE,sk);
byte bb[]={76,114,-8,-106,-48,-75,-64,16,80,-106,106,-96,-25,61,124,-61};//0123456789的DES加密數組
byte decode[]=c.doFinal(bb);
System.out.println("\n"+new String(decode));

在這里可以看到有關JCA的說明：http://java.sun.com/javase/6/docs/technotes/guides/security/crypto/CryptoSpec.html#Cipher

E. java des 加密 解密 密鑰隨機取得方法

java DES 加密 解密 生成隨機密鑰
舉例說明：
//保存生成的key
public static void saveDesKey() {
try {
SecureRandom sr = new SecureRandom();
// 選擇的DES演算法生成一個KeyGenerator對象
KeyGenerator kg = KeyGenerator.getInstance("DES");
kg.init(sr);
// 相對路徑 需要新建 conf 文件夾
// String fileName = "conf/DesKey.xml";
// 絕對路徑
String fileName = "d:/DesKey.xml";
FileOutputStream fos = new FileOutputStream(fileName);
ObjectOutputStream oos = new ObjectOutputStream(fos);
// 生成密鑰
Key key = kg.generateKey();
oos.writeObject(key);
oos.close();
} catch (Exception e) {
e.printStackTrace();
}
}
//獲取生成的key
public static Key getKey() {
Key kp = null;
try {
// 相對路徑 需要新建 conf 文件夾
// String fileName = "conf/DesKey.xml";
// InputStream is = Encrypt.class.getClassLoader().getResourceAsStream(fileName);
// 絕對路徑
String fileName = "d:/DesKey.xml";
FileInputStream is = new FileInputStream(fileName);
ObjectInputStream oos = new ObjectInputStream(is);
kp = (Key) oos.readObject();
oos.close();
} catch (Exception e) {
e.printStackTrace();
}
return kp;
}
//加密開始
public static void encrypt(String file, String dest) throws Exception {
Cipher cipher = Cipher.getInstance("DES");
cipher.init(Cipher.ENCRYPT_MODE, getKey());
InputStream is = new FileInputStream(file);
OutputStream out = new FileOutputStream(dest);
CipherInputStream cis = new CipherInputStream(is, cipher);
byte[] buffer = new byte[1024];
int r;
while ((r = cis.read(buffer)) > 0) {
out.write(buffer, 0, r);
}
cis.close();
is.close();
out.close();
}
//解密開始
public static void decrypt(String file, String dest) throws Exception {
Cipher cipher = Cipher.getInstance("DES");
cipher.init(Cipher.DECRYPT_MODE, getKey());
InputStream is = new FileInputStream(file);
OutputStream out = new FileOutputStream(dest);
CipherOutputStream cos = new CipherOutputStream(out, cipher);
byte[] buffer = new byte[1024];
int r;
while ((r = is.read(buffer)) >= 0) {
cos.write(buffer, 0, r);
}
cos.close();
out.close();
is.close();
}
}
//des加密主方法
public class DES {
public static void main(String[] args) throws Exception {
Encrypt.saveDesKey();
System.out.println("生成key");
Encrypt.getKey();
System.out.println("獲取key");
Encrypt.encrypt("d:\\hello.txt", "d:\\encrypt.txt");
System.out.println("加密");
Encrypt.decrypt("d:\\encrypt.txt", "d:\\decrypt.txt");
System.out.println("解密");
}
以上方法親測可用。

F. Des加密解密方法 用java C#和C++三種方式實現

Solaris下的系統，有一個用C做的加密工具，調用Sunwcry的des(1)對文件進行加密，然後在java中對文件進行解密。java中用的是標準的DES/CBC/NoPadding演算法，可是解密後發現開頭有8byte的數據出錯了，請高人指點一下。

cbc_encrypt.c ： 加密用的C程序

cbc_decrypt.c：解密用的C程序

TestDescbc.java：解密用的java程序

Test01.dat原始文件
Test03.dat cbc_encrypt加密後的文件
Test05.dat cbc_decrypt解密後的文件

Test06.dat TestDescbc解密後的文件

G. DES加密演算法 java實現

c語言的源代碼，供參考：

http://hi..com/gaojinshan/blog/item/8b2710c4ece4b3ce39db49e9.html

H. Java中 DES加密演算法

三個文件：
一：skey_DES.java
//對稱秘鑰生成及對象化保存
import java.io.FileOutputStream;
import java.io.ObjectOutputStream;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;

public class Skey_DES
{
public static void main(String args[])throws Exception
{
KeyGenerator kg=KeyGenerator.getInstance("DESede");
kg.init(168);
SecretKey k=kg.generateKey();
FileOutputStream f=new FileOutputStream("key1.txt");
ObjectOutputStream b= new ObjectOutputStream(f);
b.writeObject(k);
}
};

二：SEnc.java
//對稱秘鑰加密，使用位元組碼
import java.io.*;
import java.security.*;
import javax.crypto.*;

public class SEnc
{
public static void main(String args[]) throws Exception
{
String s="";

FileInputStream f=new FileInputStream("key1.txt");
ObjectInputStream b=new ObjectInputStream(f);
Key k=(Key)b.readObject();
Cipher cp=Cipher.getInstance("DESede");
cp.init(Cipher.ENCRYPT_MODE,k);

byte ptext[]=s.getBytes("UTF8");
for(int i=0;i<ptext.length;i++)
{
System.out.print(ptext[i]+",");
}
System.out.println("");
byte ctext[]=cp.doFinal(ptext);
for(int i=0;i<ctext.length;i++)
{
System.out.print(ctext[i]+",");
}
FileOutputStream f2=new FileOutputStream("SEnc.txt");
f2.write(ctext);
}
};
三：SDec.java
//使用對稱秘鑰解密
import java.io.*;
import java.security.*;
import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;

public class SDec
{
public static void main(String args[])throws Exception
{
FileInputStream f=new FileInputStream("SEnc.txt");
int num=f.available();
byte[] ctext=new byte[num];
f.read(ctext);

FileInputStream f2=new FileInputStream("key1.txt");
ObjectInputStream b=new ObjectInputStream(f2);
Key k=(Key)b.readObject();
Cipher cp=Cipher.getInstance("DESede");
cp.init(Cipher.DECRYPT_MODE,k);

byte[] ptext=cp.doFinal(ctext);
String p=new String(ptext,"UTF8");
System.out.println(p);
}
};

I. 如何使用JAVA實現對字元串的DES加密和解密

/**
*ECB模式的des加密，以base64的編碼輸出
*@parammessage
*@paramkey
*@return
*@throwsException
*/
publicstaticStringdesEncrypt(Stringmessage,Stringkey)throwsException{
//DES/ECBCBCCFBOFB/PKCS5PaddingNoPadding加密/模式/填充
Ciphercipher=Cipher.getInstance("DES");//默認就是DES/ECB/PKCS5Padding
DESKeySpecdesKeySpec=newDESKeySpec(key.getBytes());
SecretKeyFactorykeyFactory=SecretKeyFactory.getInstance("DES");
SecretKeysecretKey=keyFactory.generateSecret(desKeySpec);
cipher.init(1,secretKey);
returnnewBASE64Encoder().encode(cipher.doFinal(message.getBytes("UTF-8")));
}
/**
*ECB模式的des解密
*@parammessage
*@paramkey
*@return
*@throwsException
*/
publicstaticStringdesDecrypt(Stringmessage,Stringkey)throwsException{
Ciphercipher=Cipher.getInstance("DES");
DESKeySpecdesKeySpec=newDESKeySpec(key.getBytes());
SecretKeyFactorykeyFactory=SecretKeyFactory.getInstance("DES");
SecretKeysecretKey=keyFactory.generateSecret(desKeySpec);
cipher.init(2,secretKey);
returnnewString(cipher.doFinal(Base64.decode(message)),"UTF-8");
}

你自己寫main方法測試一下，應該是沒問題的