crypttool.java

本程序是作者开发的一个宽带娱乐系统的一个模块.

package com.singnet.util;

import java.io.*;
import java.security.*;

import javax.crypto.*;
import javax.crypto.spec.SecretKeySpec;


public class CryptTool {

    public CryptTool() {
    }
     /**
     * 生成3DES密钥.
     *
     * @param key_byte seed key
     * @throws Exception
     * @return javax.crypto.SecretKey Generated DES key
     */
    public static javax.crypto.SecretKey genDESKey(byte[] key_byte) throws
            Exception {
        SecretKey k = null;
        k = new SecretKeySpec(key_byte, "DESede");
        return k;
    }

    /**
     * 3DES 解密(byte[]).
     *
     * @param key SecretKey
     * @param crypt byte[]
     * @throws Exception
     * @return byte[]
     */
    public static byte[] desDecrypt(javax.crypto.SecretKey key, byte[] crypt) throws
            Exception {
        javax.crypto.Cipher cipher = javax.crypto.Cipher.getInstance("DESede");
        cipher.init(javax.crypto.Cipher.DECRYPT_MODE, key);
        return cipher.doFinal(crypt);
    }

    /**
     * 3DES 解密(String).
     *
     * @param key SecretKey
     * @param crypt byte[]
     * @throws Exception
     * @return byte[]
     */
    public static String desDecrypt(javax.crypto.SecretKey key, String crypt) throws
            Exception {
        return new String(desDecrypt(key, crypt.getBytes()));
    }

    /**
     * 3DES加密(byte[]).
     *
     * @param key SecretKey
     * @param src byte[]
     * @throws Exception
     * @return byte[]
     */
    public static byte[] desEncrypt(javax.crypto.SecretKey key, byte[] src) throws
            Exception {
        javax.crypto.Cipher cipher = javax.crypto.Cipher.getInstance("DESede");
        cipher.init(javax.crypto.Cipher.ENCRYPT_MODE, key);
        return cipher.doFinal(src);
    }

    /**
     * 3DES加密(String).
     *
     * @param key SecretKey
     * @param src byte[]
     * @throws Exception
     * @return byte[]
     */
    public static String desEncrypt(javax.crypto.SecretKey key, String src) throws
            Exception {
        return new String(desEncrypt(key, src.getBytes()));
    }

    /**
     * MD5 摘要计算(byte[]).
     *
     * @param src byte[]
     * @throws Exception
     * @return byte[] 16 bit digest
     */
    public static byte[] md5Digest(byte[] src) throws Exception {
        java.security.MessageDigest alg =
                java.security.MessageDigest.getInstance("MD5");
            // MD5 is 16 bit message digest

        return alg.digest(src);
    }

    /**
     * MD5 摘要计算(String).
     *
     * @param src String
     * @throws Exception
     * @return String
     */
    public static String md5Digest(String src) throws Exception {
        return new String(md5Digest(src.getBytes()));
    }

    /**
     * BASE64 编码.
     *
     * @param src String inputed string
     * @return String returned string
     */
    public static String base64Encode(String src) {
        sun.misc.BASE64Encoder encoder = new sun.misc.BASE64Encoder();

        return encoder.encode(src.getBytes());
    }

    /**
     * BASE64 编码(byte[]).
     *
     * @param src byte[] inputed string
     * @return String returned string
     */
    public static String base64Encode(byte[] src) {
        sun.misc.BASE64Encoder encoder = new sun.misc.BASE64Encoder();

        return encoder.encode(src);
    }

    /**
     * BASE64 解码.
     *
     * @param src String inputed string
     * @return String returned string
     */
    public static String base64Decode(String src) {
        sun.misc.BASE64Decoder decoder = new sun.misc.BASE64Decoder();

        try {
            return new String(decoder.decodeBuffer(src));
        } catch (Exception ex) {
            return null;
        }

    }

    /**
     * BASE64 解码(to byte[]).
     *
     * @param src String inputed string
     * @return String returned string
     */
    public static byte[] base64DecodeToBytes(String src) {
        sun.misc.BASE64Decoder decoder = new sun.misc.BASE64Decoder();

        try {
            return decoder.decodeBuffer(src);
        } catch (Exception ex) {
            return null;
        }

    }

    /**
     * 对给定字符进行 URL 编码.
     *
     * @param src String
     * @return String
     */
    public static String urlEncode(String src) {
        try {
            src = java.net.URLEncoder.encode(src, "GBK");

            return src;
        } catch (Exception ex) {
            ex.printStackTrace();
        }

        return src;
    }

    /**
     * 对给定字符进行 URL 解码
     * @param value 解码前的字符串
     * @return 解码后的字符串
     */
    public String urlDecode(String value) {
        try {
            return java.net.URLDecoder.decode(value, "GBK");
        } catch (Exception ex) {
            ex.printStackTrace();
        }

        return value;
    }
}