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  • java 路径处理工具类PathUtils.java UIDGenerator.java Base64.java

    更多工具类详见:commons-codec

    http://commons.apache.org/codec/download_codec.cgi 下载

    PathUtils.java

    /** 
     * <p>java路径处理</p> 
     * 类的目的介绍等注释
     * 
     * 
    @author  Jif  liaojifeng@163.com
     * 
    @version v1.0
     * @Timer   2011-10-12 上午12:13:47
     * ----------------------------------------------------------------------------
     * Copyright (c) 2011
     * Company   成都……有限责任公司
     * ----------------------------------------------------------------------------
    */ 
    package cn.net.comsys.license.util;

    import java.io.File;
    import java.io.IOException;
    import java.io.UnsupportedEncodingException;
    import java.net.URI;
    import java.net.URISyntaxException;
    import java.net.URL;
    import java.net.URLDecoder;

    import sun.applet.Main;


    public class PathUtils {
        /**
         * 获取当前运行程序jar包所在路径
         * 
    @return
         * 
    @throws UnsupportedEncodingException
         
    */
        public static String getProjectPath() throws UnsupportedEncodingException{
            URL url = PathUtils.class.getProtectionDomain().getCodeSource().getLocation();
            String filePath = URLDecoder.decode(url.getPath(), "UTF-8");
            if(filePath.endsWith(".jar"))
                filePath = filePath.substring(0, filePath.lastIndexOf("/") + 1);
            return filePath;
        }
        /**
         * 返回当前classpath路径
         * 
    @return
         * 
    @throws IOException
         
    */
        public static String currentPath() throws IOException{
            File   directory =   new   File( ". "); 
            //取得当前路径
            return directory.getCanonicalPath(); 

        }
        /**
         * 获取一个Class的绝对路径
         * 
         * 
    @param clazz
         * 
    @return Class的绝对路径
         * 
         
    */
        public static String getPathByClass(Class clazz) {
                String path = null;
                try {
                        URI uri = clazz.getResource("").toURI();
                        File file = new File(uri);
                        path = file.getCanonicalPath();
                } catch (URISyntaxException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                } catch (IOException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                }

                return path;

        }
        
        /**
         * 获取一个文件相对于一个Class相对的绝对路径
         * 
         * 
    @param clazz
         *            Class对象
         * 
    @param relativePath
         *            Class对象的相对路径
         * 
    @return 文件绝对路径
         
    */
        public static String getFilePathByClass(Class clazz, String relativePath) {
                String filePath = null;
                String clazzPath = getPathByClass(clazz);
                StringBuffer sbPath = new StringBuffer(clazzPath);
                sbPath.append(File.separator);
                sbPath.append(relativePath);
                File file = new File(sbPath.toString());
                try {
                        filePath = file.getCanonicalPath();
                } catch (IOException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                }

                return filePath;

        }


        public static void main(String[] args) throws IOException {
            System.out.println(PathUtils.getFilePathByClass(PathUtils.class,"../"));
        }
    }

    sd

    UUIDGenerator.java

    /** 
     * <p>产生UUID</p> 
     * 类的目的介绍等注释
     * 
     * 
    @author  Jif  liaojifeng@163.com
     * 
    @version v1.0
     * @Timer   2011-10-10 下午07:10:00
     * ----------------------------------------------------------------------------
     * Copyright (c) 2011
     * Company   成都……有限责任公司
     * ----------------------------------------------------------------------------
    */ 
    package cn.net.comsys.license.cert.util;

    import java.util.UUID;

    /**UUID的生成
     *   @creator       
     *   @create-time   2009-1-5   ????12:50:11   
     
    */

    public class UUIDGenerator {
      public UUIDGenerator() {    
       }    
          /**
           * 随机生成的UUID
           * 
    @return    随机生成的UUID
           
    */
      public static String getUUID(){    
       String s = UUID.randomUUID().toString();    
      //
      return s.substring(0,8)+s.substring(9,13)+s.substring(14,18)+s.substring(19,23)+s.substring(24);    
       }    
      /**
       * 随机生成的UUID
       * 
    @param number 随机数
       * 
    @return    随机生成的UUID
       
    */
      public static String[] getUUID(int number){    
      if(number < 1){    
      return null;    
       }    
       String[] ss = new String[number];    
      for(int i=0;i<number;i++){    
       ss[i] = getUUID();    
       }    
      return ss;    
       }    
      /**
       * 用于测试
       * 
    @param args
       
    */
      public static void main(String[] args){    
       String[] ss = getUUID(10);    
      for(int i=0;i<ss.length;i++){    
       System.out.println(ss[i]);    
       }    
       }    

    Base64.java

    /**
     * <p>类功能简述</p>
     * 类的目的介绍等注释
     *
     * @author  Jif  liaojifeng@163.com
     * @version v1.0
     * @Timer   2011-10-10 下午10:24:55
     * ----------------------------------------------------------------------------
     * Copyright (c) 2011
     * Company   成都康赛电子科大信息技术有限责任公司
     * ----------------------------------------------------------------------------
    */
    package cn.net.comsys.license.app;

    import java.util.Arrays;

    /**

     * A very fast and memory efficient class to encode and decode to and from

     * BASE64 in full accordance with RFC 2045.<br>

     * <br>

     * On Windows XP sp1 with 1.4.2_04 and later ;), this encoder and decoder is

     * about 10 times faster on small arrays (10 - 1000 bytes) and 2-3 times as fast

     * on larger arrays (10000 - 1000000 bytes) compared to

     * <code>sun.misc.Encoder()/Decoder()</code>.<br>

     * <br>

     *

     * On byte arrays the encoder is about 20% faster than Jakarta Commons Base64

     * Codec for encode and about 50% faster for decoding large arrays. This

     * implementation is about twice as fast on very small arrays (< 30 bytes). If

     * source/destination is a <code>String</code> this version is about three

     * times as fast due to the fact that the Commons Codec result has to be recoded

     * to a <code>String</code> from <code>byte[]</code>, which is very

     * expensive.<br>

     * <br>

     *

     * This encode/decode algorithm doesn't create any temporary arrays as many

     * other codecs do, it only allocates the resulting array. This produces less

     * garbage and it is possible to handle arrays twice as large as algorithms that

     * create a temporary array. (E.g. Jakarta Commons Codec). It is unknown whether

     * Sun's <code>sun.misc.Encoder()/Decoder()</code> produce temporary arrays

     * but since performance is quite low it probably does.<br>

     * <br>

     *

     * The encoder produces the same output as the Sun one except that the Sun's

     * encoder appends a trailing line separator if the last character isn't a pad.

     * Unclear why but it only adds to the length and is probably a side effect.

     * Both are in conformance with RFC 2045 though.<br>

     * Commons codec seem to always att a trailing line separator.<br>

     * <br>

     *

     * <b>Note!</b> The encode/decode method pairs (types) come in three versions

     * with the <b>exact</b> same algorithm and thus a lot of code redundancy. This

     * is to not create any temporary arrays for transcoding to/from different

     * format types. The methods not used can simply be commented out.<br>

     * <br>

     *

     * There is also a "fast" version of all decode methods that works the same way

     * as the normal ones, but har a few demands on the decoded input. Normally

     * though, these fast verions should be used if the source if the input is known

     * and it hasn't bee tampered with.<br>

     * <br>

     *

     * If you find the code useful or you find a bug, please send me a note at

     * base64 @ miginfocom . com.

     *

     * Licence (BSD): ==============

     *

     * Copyright (c) 2004, Mikael Grev, MiG InfoCom AB. (base64 @ miginfocom . com)

     * All rights reserved.

     *

     * Redistribution and use in source and binary forms, with or without

     * modification, are permitted provided that the following conditions are met:

     * Redistributions of source code must retain the above copyright notice, this

     * list of conditions and the following disclaimer. Redistributions in binary

     * form must reproduce the above copyright notice, this list of conditions and

     * the following disclaimer in the documentation and/or other materials provided

     * with the distribution. Neither the name of the MiG InfoCom AB nor the names

     * of its contributors may be used to endorse or promote products derived from

     * this software without specific prior written permission.

     *

     * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

     * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

     * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

     * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE

     * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

     * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

     * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

     * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN

     * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

     * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

     * POSSIBILITY OF SUCH DAMAGE.

     *

     * @version 2.2

     * @author Mikael Grev Date: 2004-aug-02 Time: 11:31:11

     */

    public class Base64 {

            private static final boolean devLineSep = true;

            private static final char[] CA = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"

                            .toCharArray();

            private static final int[] IA = new int[256];

            static {

                    Arrays.fill(IA, -1);

                    for (int i = 0, iS = CA.length; i < iS; i++)

                            IA[CA[i]] = i;

                    IA['='] = 0;

            }

            // ****************************************************************************************

            // * char[] version

            // ****************************************************************************************

            public final static char[] encodeToChar(byte[] sArr) {

                    return encodeToChar(sArr, devLineSep);

            }

            /**

             * Encodes a raw byte array into a BASE64 <code>char[]</code>

             * representation i accordance with RFC 2045.

             *

             * @param sArr

             *            The bytes to convert. If <code>null</code> or length 0 an

             *            empty array will be returned.

             * @param lineSep

             *            Optional "/r/n" after 76 characters, unless end of file.<br>

             *            No line separator will be in breach of RFC 2045 which

             *            specifies max 76 per line but will be a little faster.

             * @return A BASE64 encoded array. Never <code>null</code>.

             */

            public final static char[] encodeToChar(byte[] sArr, boolean lineSep) {

                    // Check special case

                    int sLen = sArr != null ? sArr.length : 0;

                    if (sLen == 0)

                            return new char[0];

                    int eLen = (sLen / 3) * 3; // Length of even 24-bits.

                    int cCnt = ((sLen - 1) / 3 + 1) << 2; // Returned character count

                    int dLen = cCnt + (lineSep ? (cCnt - 1) / 76 << 1 : 0); // Length of

                    // returned

                    // array

                    char[] dArr = new char[dLen];

                    // Encode even 24-bits

                    for (int s = 0, d = 0, cc = 0; s < eLen;) {

                            // Copy next three bytes into lower 24 bits of int, paying attension

                            // to sign.

                            int i = (sArr[s++] & 0xff) << 16 | (sArr[s++] & 0xff) << 8

                                            | (sArr[s++] & 0xff);

                            // Encode the int into four chars

                            dArr[d++] = CA[(i >>> 18) & 0x3f];

                            dArr[d++] = CA[(i >>> 12) & 0x3f];

                            dArr[d++] = CA[(i >>> 6) & 0x3f];

                            dArr[d++] = CA[i & 0x3f];

                            // Add optional line separator

                            if (lineSep && ++cc == 19 && d < dLen - 2) {

                                    dArr[d++] = 'r';

                                    dArr[d++] = 'n';

                                    cc = 0;

                            }

                    }

                    // Pad and encode last bits if source isn't even 24 bits.

                    int left = sLen - eLen; // 0 - 2.

                    if (left > 0) {

                            // Prepare the int

                            int i = ((sArr[eLen] & 0xff) << 10)

                                            | (left == 2 ? ((sArr[sLen - 1] & 0xff) << 2) : 0);

                            // Set last four chars

                            dArr[dLen - 4] = CA[i >> 12];

                            dArr[dLen - 3] = CA[(i >>> 6) & 0x3f];

                            dArr[dLen - 2] = left == 2 ? CA[i & 0x3f] : '=';

                            dArr[dLen - 1] = '=';

                    }

                    return dArr;

            }

            /**

             * Decodes a BASE64 encoded char array. All illegal characters will be

             * ignored and can handle both arrays with and without line separators.

             *

             * @param sArr

             *            The source array. <code>null</code> or length 0 will return

             *            an empty array.

             * @return The decoded array of bytes. May be of length 0. Will be

             *         <code>null</code> if the legal characters (including '=') isn't

             *         divideable by 4. (I.e. definitely corrupted).

             */

            public final static byte[] decode(char[] sArr) {

                    // Check special case

                    int sLen = sArr != null ? sArr.length : 0;

                    if (sLen == 0)

                            return new byte[0];

                    // Count illegal characters (including '/r', '/n') to know what size the

                    // returned array will be,

                    // so we don't have to reallocate & copy it later.

                    int sepCnt = 0; // Number of separator characters. (Actually illegal

                    // characters, but that's a bonus...)

                    for (int i = 0; i < sLen; i++)

                            // If input is "pure" (I.e. no line separators or illegal chars)

                            // base64 this loop can be commented out.

                            if (IA[sArr[i]] < 0)

                                    sepCnt++;

                    // Check so that legal chars (including '=') are evenly divideable by 4

                    // as specified in RFC 2045.

                    if ((sLen - sepCnt) % 4 != 0)

                            return null;

                    int pad = 0;

                    for (int i = sLen; i > 1 && IA[sArr[--i]] <= 0;)

                            if (sArr[i] == '=')

                                    pad++;

                    int len = ((sLen - sepCnt) * 6 >> 3) - pad;

                    byte[] dArr = new byte[len]; // Preallocate byte[] of exact length

                    for (int s = 0, d = 0; d < len;) {

                            // Assemble three bytes into an int from four "valid" characters.

                            int i = 0;

                            for (int j = 0; j < 4; j++) { // j only increased if a valid char

                                    // was found.

                                    int c = IA[sArr[s++]];

                                    if (c >= 0)

                                            i |= c << (18 - j * 6);

                                    else

                                            j--;

                            }

                            // Add the bytes

                            dArr[d++] = (byte) (i >> 16);

                            if (d < len) {

                                    dArr[d++] = (byte) (i >> 8);

                                    if (d < len)

                                            dArr[d++] = (byte) i;

                            }

                    }

                    return dArr;

            }

            /**

             * Decodes a BASE64 encoded char array that is known to be resonably well

             * formatted. The method is about twice as fast as mailto:%7B@link #decode(char[])}.

             * The preconditions are:<br> + The array must have a line length of 76

             * chars OR no line separators at all (one line).<br> + Line separator must

             * be "/r/n", as specified in RFC 2045 + The array must not contain illegal

             * characters within the encoded string<br> + The array CAN have illegal

             * characters at the beginning and end, those will be dealt with

             * appropriately.<br>

             *

             * @param sArr

             *            The source array. Length 0 will return an empty array.

             *            <code>null</code> will throw an exception.

             * @return The decoded array of bytes. May be of length 0.

             */

            public final static byte[] decodeFast(char[] sArr) {

                    // Check special case

                    int sLen = sArr.length;

                    if (sLen == 0)

                            return new byte[0];

                    int sIx = 0, eIx = sLen - 1; // Start and end index after trimming.

                    // Trim illegal chars from start

                    while (sIx < eIx && IA[sArr[sIx]] < 0)

                            sIx++;

                    // Trim illegal chars from end

                    while (eIx > 0 && IA[sArr[eIx]] < 0)

                            eIx--;

                    // get the padding count (=) (0, 1 or 2)

                    int pad = sArr[eIx] == '=' ? (sArr[eIx - 1] == '=' ? 2 : 1) : 0; // Count

                    // '='

                    // at

                    // end.

                    int cCnt = eIx - sIx + 1; // Content count including possible

                    // separators

                    int sepCnt = sLen > 76 ? (sArr[76] == 'r' ? cCnt / 78 : 0) << 1 : 0;

                    int len = ((cCnt - sepCnt) * 6 >> 3) - pad; // The number of decoded

                    // bytes

                    byte[] dArr = new byte[len]; // Preallocate byte[] of exact length

                    // Decode all but the last 0 - 2 bytes.

                    int d = 0;

                    for (int cc = 0, eLen = (len / 3) * 3; d < eLen;) {

                            // Assemble three bytes into an int from four "valid" characters.

                            int i = IA[sArr[sIx++]] << 18 | IA[sArr[sIx++]] << 12

                                            | IA[sArr[sIx++]] << 6 | IA[sArr[sIx++]];

                            // Add the bytes

                            dArr[d++] = (byte) (i >> 16);

                            dArr[d++] = (byte) (i >> 8);

                            dArr[d++] = (byte) i;

                            // If line separator, jump over it.

                            if (sepCnt > 0 && ++cc == 19) {

                                    sIx += 2;

                                    cc = 0;

                            }

                    }

                    if (d < len) {

                            // Decode last 1-3 bytes (incl '=') into 1-3 bytes

                            int i = 0;

                            for (int j = 0; sIx <= eIx - pad; j++)

                                    i |= IA[sArr[sIx++]] << (18 - j * 6);

                            for (int r = 16; d < len; r -= 8)

                                    dArr[d++] = (byte) (i >> r);

                    }

                    return dArr;

            }

            // ****************************************************************************************

            // * byte[] version

            // ****************************************************************************************

            public final static byte[] encodeToByte(byte[] sArr) {

                    return encodeToByte(sArr, devLineSep);

            }

            /**

             * Encodes a raw byte array into a BASE64 <code>byte[]</code>

             * representation i accordance with RFC 2045.

             *

             * @param sArr

             *            The bytes to convert. If <code>null</code> or length 0 an

             *            empty array will be returned.

             * @param lineSep

             *            Optional "/r/n" after 76 characters, unless end of file.<br>

             *            No line separator will be in breach of RFC 2045 which

             *            specifies max 76 per line but will be a little faster.

             * @return A BASE64 encoded array. Never <code>null</code>.

             */

            public final static byte[] encodeToByte(byte[] sArr, boolean lineSep) {

                    // Check special case

                    int sLen = sArr != null ? sArr.length : 0;

                    if (sLen == 0)

                            return new byte[0];

                    int eLen = (sLen / 3) * 3; // Length of even 24-bits.

                    int cCnt = ((sLen - 1) / 3 + 1) << 2; // Returned character count

                    int dLen = cCnt + (lineSep ? (cCnt - 1) / 76 << 1 : 0); // Length of

                    // returned

                    // array

                    byte[] dArr = new byte[dLen];

                    // Encode even 24-bits

                    for (int s = 0, d = 0, cc = 0; s < eLen;) {

                            // Copy next three bytes into lower 24 bits of int, paying attension

                            // to sign.

                            int i = (sArr[s++] & 0xff) << 16 | (sArr[s++] & 0xff) << 8

                                            | (sArr[s++] & 0xff);

                            // Encode the int into four chars

                            dArr[d++] = (byte) CA[(i >>> 18) & 0x3f];

                            dArr[d++] = (byte) CA[(i >>> 12) & 0x3f];

                            dArr[d++] = (byte) CA[(i >>> 6) & 0x3f];

                            dArr[d++] = (byte) CA[i & 0x3f];

                            // Add optional line separator

                            if (lineSep && ++cc == 19 && d < dLen - 2) {

                                    dArr[d++] = 'r';

                                    dArr[d++] = 'n';

                                    cc = 0;

                            }

                    }

                    // Pad and encode last bits if source isn't an even 24 bits.

                    int left = sLen - eLen; // 0 - 2.

                    if (left > 0) {

                            // Prepare the int

                            int i = ((sArr[eLen] & 0xff) << 10)

                                            | (left == 2 ? ((sArr[sLen - 1] & 0xff) << 2) : 0);

                            // Set last four chars

                            dArr[dLen - 4] = (byte) CA[i >> 12];

                            dArr[dLen - 3] = (byte) CA[(i >>> 6) & 0x3f];

                            dArr[dLen - 2] = left == 2 ? (byte) CA[i & 0x3f] : (byte) '=';

                            dArr[dLen - 1] = '=';

                    }

                    return dArr;

            }

            /**

             * Decodes a BASE64 encoded byte array. All illegal characters will be

             * ignored and can handle both arrays with and without line separators.

             *

             * @param sArr

             *            The source array. Length 0 will return an empty array.

             *            <code>null</code> will throw an exception.

             * @return The decoded array of bytes. May be of length 0. Will be

             *         <code>null</code> if the legal characters (including '=') isn't

             *         divideable by 4. (I.e. definitely corrupted).

             */

            public final static byte[] decode(byte[] sArr) {

                    // Check special case

                    int sLen = sArr.length;

                    // Count illegal characters (including '/r', '/n') to know what size the

                    // returned array will be,

                    // so we don't have to reallocate & copy it later.

                    int sepCnt = 0; // Number of separator characters. (Actually illegal

                    // characters, but that's a bonus...)

                    for (int i = 0; i < sLen; i++)

                            // If input is "pure" (I.e. no line separators or illegal chars)

                            // base64 this loop can be commented out.

                            if (IA[sArr[i] & 0xff] < 0)

                                    sepCnt++;

                    // Check so that legal chars (including '=') are evenly divideable by 4

                    // as specified in RFC 2045.

                    if ((sLen - sepCnt) % 4 != 0)

                            return null;

                    int pad = 0;

                    for (int i = sLen; i > 1 && IA[sArr[--i] & 0xff] <= 0;)

                            if (sArr[i] == '=')

                                    pad++;

                    int len = ((sLen - sepCnt) * 6 >> 3) - pad;

                    byte[] dArr = new byte[len]; // Preallocate byte[] of exact length

                    for (int s = 0, d = 0; d < len;) {

                            // Assemble three bytes into an int from four "valid" characters.

                            int i = 0;

                            for (int j = 0; j < 4; j++) { // j only increased if a valid char

                                    // was found.

                                    int c = IA[sArr[s++] & 0xff];

                                    if (c >= 0)

                                            i |= c << (18 - j * 6);

                                    else

                                            j--;

                            }

                            // Add the bytes

                            dArr[d++] = (byte) (i >> 16);

                            if (d < len) {

                                    dArr[d++] = (byte) (i >> 8);

                                    if (d < len)

                                            dArr[d++] = (byte) i;

                            }

                    }

                    return dArr;

            }

            /**

             * Decodes a BASE64 encoded byte array that is known to be resonably well

             * formatted. The method is about twice as fast as mailto:%7B@link #decode(byte[])}.

             * The preconditions are:<br> + The array must have a line length of 76

             * chars OR no line separators at all (one line).<br> + Line separator must

             * be "/r/n", as specified in RFC 2045 + The array must not contain illegal

             * characters within the encoded string<br> + The array CAN have illegal

             * characters at the beginning and end, those will be dealt with

             * appropriately.<br>

             *

             * @param sArr

             *            The source array. Length 0 will return an empty array.

             *            <code>null</code> will throw an exception.

             * @return The decoded array of bytes. May be of length 0.

             */

            public final static byte[] decodeFast(byte[] sArr) {

                    // Check special case

                    int sLen = sArr.length;

                    if (sLen == 0)

                            return new byte[0];

                    int sIx = 0, eIx = sLen - 1; // Start and end index after trimming.

                    // Trim illegal chars from start

                    while (sIx < eIx && IA[sArr[sIx] & 0xff] < 0)

                            sIx++;

                    // Trim illegal chars from end

                    while (eIx > 0 && IA[sArr[eIx] & 0xff] < 0)

                            eIx--;

                    // get the padding count (=) (0, 1 or 2)

                    int pad = sArr[eIx] == '=' ? (sArr[eIx - 1] == '=' ? 2 : 1) : 0; // Count

                    // '='

                    // at

                    // end.

                    int cCnt = eIx - sIx + 1; // Content count including possible

                    // separators

                    int sepCnt = sLen > 76 ? (sArr[76] == 'r' ? cCnt / 78 : 0) << 1 : 0;

                    int len = ((cCnt - sepCnt) * 6 >> 3) - pad; // The number of decoded

                    // bytes

                    byte[] dArr = new byte[len]; // Preallocate byte[] of exact length

                    // Decode all but the last 0 - 2 bytes.

                    int d = 0;

                    for (int cc = 0, eLen = (len / 3) * 3; d < eLen;) {

                            // Assemble three bytes into an int from four "valid" characters.

                            int i = IA[sArr[sIx++]] << 18 | IA[sArr[sIx++]] << 12

                                            | IA[sArr[sIx++]] << 6 | IA[sArr[sIx++]];

                            // Add the bytes

                            dArr[d++] = (byte) (i >> 16);

                            dArr[d++] = (byte) (i >> 8);

                            dArr[d++] = (byte) i;

                            // If line separator, jump over it.

                            if (sepCnt > 0 && ++cc == 19) {

                                    sIx += 2;

                                    cc = 0;

                            }

                    }

                    if (d < len) {

                            // Decode last 1-3 bytes (incl '=') into 1-3 bytes

                            int i = 0;

                            for (int j = 0; sIx <= eIx - pad; j++)

                                    i |= IA[sArr[sIx++]] << (18 - j * 6);

                            for (int r = 16; d < len; r -= 8)

                                    dArr[d++] = (byte) (i >> r);

                    }

                    return dArr;

            }

            // ****************************************************************************************

            // * String version

            // ****************************************************************************************

            /**

             * Encodes a raw byte array into a BASE64 <code>String</code>

             * representation i accordance with RFC 2045.

             *

             * @param sArr

             *            The bytes to convert. If <code>null</code> or length 0 an

             *            empty array will be returned.

             * @param lineSep

             *            Optional "/r/n" after 76 characters, unless end of file.<br>

             *            No line separator will be in breach of RFC 2045 which

             *            specifies max 76 per line but will be a little faster.

             * @return A BASE64 encoded array. Never <code>null</code>.

             */

            public final static String encodeToString(byte[] sArr, boolean lineSep) {

                    // Reuse char[] since we can't create a String incrementally anyway and

                    // StringBuffer/Builder would be slower.

                    return new String(encodeToChar(sArr, lineSep));

            }

            public final static String encodeToString(byte[] sArr) {

                    // Reuse char[] since we can't create a String incrementally anyway and

                    // StringBuffer/Builder would be slower.

                    return new String(encodeToChar(sArr, devLineSep));

            }

            /**

             * Decodes a BASE64 encoded <code>String</code>. All illegal characters

             * will be ignored and can handle both strings with and without line

             * separators.<br>

             * <b>Note!</b> It can be up to about 2x the speed to call

             * <code>decode(str.toCharArray())</code> instead. That will create a

             * temporary array though. This version will use <code>str.charAt(i)</code>

             * to iterate the string.

             *

             * @param str

             *            The source string. <code>null</code> or length 0 will return

             *            an empty array.

             * @return The decoded array of bytes. May be of length 0. Will be

             *         <code>null</code> if the legal characters (including '=') isn't

             *         divideable by 4. (I.e. definitely corrupted).

             */

            public final static byte[] decode(String str) {

                    // Check special case

                    int sLen = str != null ? str.length() : 0;

                    if (sLen == 0)

                            return new byte[0];

                    // Count illegal characters (including '/r', '/n') to know what size the

                    // returned array will be,

                    // so we don't have to reallocate & copy it later.

                    int sepCnt = 0; // Number of separator characters. (Actually illegal

                    // characters, but that's a bonus...)

                    for (int i = 0; i < sLen; i++)

                            // If input is "pure" (I.e. no line separators or illegal chars)

                            // base64 this loop can be commented out.

                            if (IA[str.charAt(i)] < 0)

                                    sepCnt++;

                    // Check so that legal chars (including '=') are evenly divideable by 4

                    // as specified in RFC 2045.

                    if ((sLen - sepCnt) % 4 != 0)

                            return null;

                    // Count '=' at end

                    int pad = 0;

                    for (int i = sLen; i > 1 && IA[str.charAt(--i)] <= 0;)

                            if (str.charAt(i) == '=')

                                    pad++;

                    int len = ((sLen - sepCnt) * 6 >> 3) - pad;

                    byte[] dArr = new byte[len]; // Preallocate byte[] of exact length

                    for (int s = 0, d = 0; d < len;) {

                            // Assemble three bytes into an int from four "valid" characters.

                            int i = 0;

                            for (int j = 0; j < 4; j++) { // j only increased if a valid char

                                    // was found.

                                    int c = IA[str.charAt(s++)];

                                    if (c >= 0)

                                            i |= c << (18 - j * 6);

                                    else

                                            j--;

                            }

                            // Add the bytes

                            dArr[d++] = (byte) (i >> 16);

                            if (d < len) {

                                    dArr[d++] = (byte) (i >> 8);

                                    if (d < len)

                                            dArr[d++] = (byte) i;

                            }

                    }

                    return dArr;

            }

            /**

             * Decodes a BASE64 encoded string that is known to be resonably well

             * formatted. The method is about twice as fast as mailto:%7B@link #decode(String)}.

             * The preconditions are:<br> + The array must have a line length of 76

             * chars OR no line separators at all (one line).<br> + Line separator must

             * be "/r/n", as specified in RFC 2045 + The array must not contain illegal

             * characters within the encoded string<br> + The array CAN have illegal

             * characters at the beginning and end, those will be dealt with

             * appropriately.<br>

             *

             * @param s

             *            The source string. Length 0 will return an empty array.

             *            <code>null</code> will throw an exception.

             * @return The decoded array of bytes. May be of length 0.

             */

            public final static byte[] decodeFast(String s) {

                    // Check special case

                    int sLen = s.length();

                    if (sLen == 0)

                            return new byte[0];

                    int sIx = 0, eIx = sLen - 1; // Start and end index after trimming.

                    // Trim illegal chars from start

                    while (sIx < eIx && IA[s.charAt(sIx) & 0xff] < 0)

                            sIx++;

                    // Trim illegal chars from end

                    while (eIx > 0 && IA[s.charAt(eIx) & 0xff] < 0)

                            eIx--;

                    // get the padding count (=) (0, 1 or 2)

                    int pad = s.charAt(eIx) == '=' ? (s.charAt(eIx - 1) == '=' ? 2 : 1) : 0; // Count

                    // '='

                    // at

                    // end.

                    int cCnt = eIx - sIx + 1; // Content count including possible

                    // separators

                    int sepCnt = sLen > 76 ? (s.charAt(76) == 'r' ? cCnt / 78 : 0) << 1

                                    : 0;

                    int len = ((cCnt - sepCnt) * 6 >> 3) - pad; // The number of decoded

                    // bytes

                    byte[] dArr = new byte[len]; // Preallocate byte[] of exact length

                    // Decode all but the last 0 - 2 bytes.

                    int d = 0;

                    for (int cc = 0, eLen = (len / 3) * 3; d < eLen;) {

                            // Assemble three bytes into an int from four "valid" characters.

                            int i = IA[s.charAt(sIx++)] << 18 | IA[s.charAt(sIx++)] << 12

                                            | IA[s.charAt(sIx++)] << 6 | IA[s.charAt(sIx++)];

                            // Add the bytes

                            dArr[d++] = (byte) (i >> 16);

                            dArr[d++] = (byte) (i >> 8);

                            dArr[d++] = (byte) i;

                            // If line separator, jump over it.

                            if (sepCnt > 0 && ++cc == 19) {

                                    sIx += 2;

                                    cc = 0;

                            }

                    }

                    if (d < len) {

                            // Decode last 1-3 bytes (incl '=') into 1-3 bytes

                            int i = 0;

                            for (int j = 0; sIx <= eIx - pad; j++)

                                    i |= IA[s.charAt(sIx++)] << (18 - j * 6);

                            for (int r = 16; d < len; r -= 8)

                                    dArr[d++] = (byte) (i >> r);

                    }

                    return dArr;

            }

       /**
        * 创建指定的目录。
        * 如果指定的目录的父目录不存在则创建其目录书上所有需要的父目录。
        * <b>注意:可能会在返回false的时候创建部分父目录。</b>
        * @param file 要创建的目录
        * @return 完全创建成功时返回true,否则返回false。
        * @since  0.1
        */
       public static boolean makeDirectory(File file) {
         File parent = file.getParentFile();
         if (parent != null) {
           return parent.mkdirs();
         }
         return false;
       }

            public static void main(String[] args){
    /**
     * NUNDOUQ5QjQ4RUZDRjJGREI3NjZCRkIwMEUwOEVFREY=
     * 123$/\
     */
                    System.out.println(Base64.encodeToString("5CC9D9B48EFCF2FDB766BFB00E08EEDF".getBytes()));
                    System.out.println(new String(Base64.decode("MTIzJC9c")));
            }

    }

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  • 原文地址:https://www.cnblogs.com/jifeng/p/2208035.html
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