org.demo.show.providers.ThreeDes2.java Source code

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Here is the source code for org.demo.show.providers.ThreeDes2.java

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/*
 * Copyright 2002-2101 SIM group.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.demo.show.providers;

import java.security.Key;
import java.security.Security;

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESedeKeySpec;

import org.apache.commons.codec.binary.Base64;

/**
 * 
 * @CreateTime 2015424 ?6:03:08
 * 
 * @author chao.yu
 *
 * @version 1.0
 *
 */
public class ThreeDes2 {

    /**
     * 
     * */
    public static final String KEY_ALGORITHM = "DESede";

    /**
     * //?/?
     * */
    public static final String CIPHER_ALGORITHM = "DESede/ECB/PKCS5Padding";

    /**
     * 
     * ?
     * 
     * @return byte[] 
     * */
    public static byte[] initkey() throws Exception {

        // ?
        KeyGenerator kg = KeyGenerator.getInstance(KEY_ALGORITHM);
        // ??
        kg.init(168);
        // ?
        SecretKey secretKey = kg.generateKey();
        // ???
        return secretKey.getEncoded();
    }

    /**
     * ?
     * 
     * @param key
     *            
     * @return Key 
     * */
    public static Key toKey(byte[] key) throws Exception {
        // Des
        DESedeKeySpec dks = new DESedeKeySpec(key);
        // 
        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(KEY_ALGORITHM);
        // ?
        SecretKey secretKey = keyFactory.generateSecret(dks);
        return secretKey;
    }

    /**
     * ?
     * 
     * @param data
     *            ?
     * @param key
     *            
     * @return byte[] ??
     * */
    public static byte[] encrypt(byte[] data, byte[] key) throws Exception {
        // 
        Key k = toKey(key);
        // 
        Cipher cipher = Cipher.getInstance(CIPHER_ALGORITHM);
        // ??
        cipher.init(Cipher.ENCRYPT_MODE, k);
        // ?
        return cipher.doFinal(data);
    }

    /**
     * ?
     * 
     * @param data
     *            ?
     * @param key
     *            
     * @return byte[] ??
     * */
    public static byte[] decrypt(byte[] data, byte[] key) throws Exception {
        // 
        Key k = toKey(key);
        // 
        Cipher cipher = Cipher.getInstance(CIPHER_ALGORITHM);
        // ??
        cipher.init(Cipher.DECRYPT_MODE, k);
        // ?
        return cipher.doFinal(data);
    }

    /**
     * 
     * 
     * @throws Exception
     */
    public static void main(String[] args) throws Exception {
        Security.addProvider(new com.sun.crypto.provider.SunJCE());
        String str = "DESede";
        System.out.println("" + str);
        // ?
        byte[] key = ThreeDes2.initkey();
        System.out.println("" + new String(Base64.encodeBase64(key)));
        // ?
        byte[] data = ThreeDes2.encrypt(str.getBytes(), key);
        System.out.println("?" + new String(Base64.encodeBase64(data)));
        // ?
        data = ThreeDes2.decrypt(data, key);
        System.out.println("?" + new String(data));
    }

}