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  • Base64加密,解密

    加密解密示例:

     //base64进行加密解密,通常用作对二进制数据进行加密
    String body = "水狼一族";
    byte[] base64Encrypt = Base64Util.base64Encrypt(body);
    String toHexString = HexUtils.toHexString(base64Encrypt);
    System.out.println(toHexString);
    byte[] tobyte = HexUtils.fromHexString(toHexString);
    byte[] base64Decrypt = Base64Util.base64Decrypt(tobyte);
    System.out.println(new String(base64Decrypt));

    下面是涉及到的四个相关类:

    (1)Base64类:

    /**
     * @Description: base64加密,解密工具类
     * @author: shuilangyizu
     * @date: 2021年07月28日 15:55
     */
    package com.shuilangyizu.logistics;
    
    import java.io.FilterOutputStream;
    import java.io.InputStream;
    import java.io.IOException;
    import java.io.OutputStream;
    import java.nio.ByteBuffer;
    import java.nio.charset.StandardCharsets;
    import java.util.Arrays;
    import java.util.Objects;
    
    /**
     * This class consists exclusively of static methods for obtaining
     * encoders and decoders for the Base64 encoding scheme. The
     * implementation of this class supports the following types of Base64
     * as specified in
     * <a href="http://www.ietf.org/rfc/rfc4648.txt">RFC 4648</a> and
     * <a href="http://www.ietf.org/rfc/rfc2045.txt">RFC 2045</a>.
     *
     * <ul>
     * <li><a name="basic"><b>Basic</b></a>
     * <p> Uses "The Base64 Alphabet" as specified in Table 1 of
     *     RFC 4648 and RFC 2045 for encoding and decoding operation.
     *     The encoder does not add any line feed (line separator)
     *     character. The decoder rejects data that contains characters
     *     outside the base64 alphabet.</p></li>
     *
     * <li><a name="url"><b>URL and Filename safe</b></a>
     * <p> Uses the "URL and Filename safe Base64 Alphabet" as specified
     *     in Table 2 of RFC 4648 for encoding and decoding. The
     *     encoder does not add any line feed (line separator) character.
     *     The decoder rejects data that contains characters outside the
     *     base64 alphabet.</p></li>
     *
     * <li><a name="mime"><b>MIME</b></a>
     * <p> Uses the "The Base64 Alphabet" as specified in Table 1 of
     *     RFC 2045 for encoding and decoding operation. The encoded output
     *     must be represented in lines of no more than 76 characters each
     *     and uses a carriage return {@code '
    '} followed immediately by
     *     a linefeed {@code '
    '} as the line separator. No line separator
     *     is added to the end of the encoded output. All line separators
     *     or other characters not found in the base64 alphabet table are
     *     ignored in decoding operation.</p></li>
     * </ul>
     *
     * <p> Unless otherwise noted, passing a {@code null} argument to a
     * method of this class will cause a {@link java.lang.NullPointerException
     * NullPointerException} to be thrown.
     *
     * @author  Xueming Shen
     * @since   1.8
     */
    
    public class Base64 {
    
        private Base64() {}
    
        /**
         * Returns a {@link Encoder} that encodes using the
         * <a href="#basic">Basic</a> type base64 encoding scheme.
         *
         * @return  A Base64 encoder.
         */
        public static Encoder getEncoder() {
             return Encoder.RFC4648;
        }
    
        /**
         * Returns a {@link Encoder} that encodes using the
         * <a href="#url">URL and Filename safe</a> type base64
         * encoding scheme.
         *
         * @return  A Base64 encoder.
         */
        public static Encoder getUrlEncoder() {
             return Encoder.RFC4648_URLSAFE;
        }
    
        /**
         * Returns a {@link Encoder} that encodes using the
         * <a href="#mime">MIME</a> type base64 encoding scheme.
         *
         * @return  A Base64 encoder.
         */
        public static Encoder getMimeEncoder() {
            return Encoder.RFC2045;
        }
    
        /**
         * Returns a {@link Encoder} that encodes using the
         * <a href="#mime">MIME</a> type base64 encoding scheme
         * with specified line length and line separators.
         *
         * @param   lineLength
         *          the length of each output line (rounded down to nearest multiple
         *          of 4). If {@code lineLength <= 0} the output will not be separated
         *          in lines
         * @param   lineSeparator
         *          the line separator for each output line
         *
         * @return  A Base64 encoder.
         *
         * @throws  IllegalArgumentException if {@code lineSeparator} includes any
         *          character of "The Base64 Alphabet" as specified in Table 1 of
         *          RFC 2045.
         */
        public static Encoder getMimeEncoder(int lineLength, byte[] lineSeparator) {
             Objects.requireNonNull(lineSeparator);
             int[] base64 = Decoder.fromBase64;
             for (byte b : lineSeparator) {
                 if (base64[b & 0xff] != -1)
                     throw new IllegalArgumentException(
                         "Illegal base64 line separator character 0x" + Integer.toString(b, 16));
             }
             if (lineLength <= 0) {
                 return Encoder.RFC4648;
             }
             return new Encoder(false, lineSeparator, lineLength >> 2 << 2, true);
        }
    
        /**
         * Returns a {@link Decoder} that decodes using the
         * <a href="#basic">Basic</a> type base64 encoding scheme.
         *
         * @return  A Base64 decoder.
         */
        public static Decoder getDecoder() {
             return Decoder.RFC4648;
        }
    
        /**
         * Returns a {@link Decoder} that decodes using the
         * <a href="#url">URL and Filename safe</a> type base64
         * encoding scheme.
         *
         * @return  A Base64 decoder.
         */
        public static Decoder getUrlDecoder() {
             return Decoder.RFC4648_URLSAFE;
        }
    
        /**
         * Returns a {@link Decoder} that decodes using the
         * <a href="#mime">MIME</a> type base64 decoding scheme.
         *
         * @return  A Base64 decoder.
         */
        public static Decoder getMimeDecoder() {
             return Decoder.RFC2045;
        }
    
        /**
         * This class implements an encoder for encoding byte data using
         * the Base64 encoding scheme as specified in RFC 4648 and RFC 2045.
         *
         * <p> Instances of {@link Encoder} class are safe for use by
         * multiple concurrent threads.
         *
         * <p> Unless otherwise noted, passing a {@code null} argument to
         * a method of this class will cause a
         * {@link java.lang.NullPointerException NullPointerException} to
         * be thrown.
         *
         * @see     Decoder
         * @since   1.8
         */
        public static class Encoder {
    
            private final byte[] newline;
            private final int linemax;
            private final boolean isURL;
            private final boolean doPadding;
    
            private Encoder(boolean isURL, byte[] newline, int linemax, boolean doPadding) {
                this.isURL = isURL;
                this.newline = newline;
                this.linemax = linemax;
                this.doPadding = doPadding;
            }
    
            /**
             * This array is a lookup table that translates 6-bit positive integer
             * index values into their "Base64 Alphabet" equivalents as specified
             * in "Table 1: The Base64 Alphabet" of RFC 2045 (and RFC 4648).
             */
            private static final char[] toBase64 = {
                'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',
                'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
                'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',
                'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
                '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/'
            };
    
            /**
             * It's the lookup table for "URL and Filename safe Base64" as specified
             * in Table 2 of the RFC 4648, with the '+' and '/' changed to '-' and
             * '_'. This table is used when BASE64_URL is specified.
             */
            private static final char[] toBase64URL = {
                'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',
                'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
                'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',
                'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
                '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '-', '_'
            };
    
            private static final int MIMELINEMAX = 76;
            private static final byte[] CRLF = new byte[] {'
    ', '
    '};
    
            static final Encoder RFC4648 = new Encoder(false, null, -1, true);
            static final Encoder RFC4648_URLSAFE = new Encoder(true, null, -1, true);
            static final Encoder RFC2045 = new Encoder(false, CRLF, MIMELINEMAX, true);
    
            private final int outLength(int srclen) {
                int len = 0;
                if (doPadding) {
                    len = 4 * ((srclen + 2) / 3);
                } else {
                    int n = srclen % 3;
                    len = 4 * (srclen / 3) + (n == 0 ? 0 : n + 1);
                }
                if (linemax > 0)                                  // line separators
                    len += (len - 1) / linemax * newline.length;
                return len;
            }
    
            /**
             * Encodes all bytes from the specified byte array into a newly-allocated
             * byte array using the {@link Base64} encoding scheme. The returned byte
             * array is of the length of the resulting bytes.
             *
             * @param   src
             *          the byte array to encode
             * @return  A newly-allocated byte array containing the resulting
             *          encoded bytes.
             */
            public byte[] encode(byte[] src) {
                int len = outLength(src.length);          // dst array size
                byte[] dst = new byte[len];
                int ret = encode0(src, 0, src.length, dst);
                if (ret != dst.length)
                     return Arrays.copyOf(dst, ret);
                return dst;
            }
    
            /**
             * Encodes all bytes from the specified byte array using the
             * {@link Base64} encoding scheme, writing the resulting bytes to the
             * given output byte array, starting at offset 0.
             *
             * <p> It is the responsibility of the invoker of this method to make
             * sure the output byte array {@code dst} has enough space for encoding
             * all bytes from the input byte array. No bytes will be written to the
             * output byte array if the output byte array is not big enough.
             *
             * @param   src
             *          the byte array to encode
             * @param   dst
             *          the output byte array
             * @return  The number of bytes written to the output byte array
             *
             * @throws  IllegalArgumentException if {@code dst} does not have enough
             *          space for encoding all input bytes.
             */
            public int encode(byte[] src, byte[] dst) {
                int len = outLength(src.length);         // dst array size
                if (dst.length < len)
                    throw new IllegalArgumentException(
                        "Output byte array is too small for encoding all input bytes");
                return encode0(src, 0, src.length, dst);
            }
    
            /**
             * Encodes the specified byte array into a String using the {@link Base64}
             * encoding scheme.
             *
             * <p> This method first encodes all input bytes into a base64 encoded
             * byte array and then constructs a new String by using the encoded byte
             * array and the {@link java.nio.charset.StandardCharsets#ISO_8859_1
             * ISO-8859-1} charset.
             *
             * <p> In other words, an invocation of this method has exactly the same
             * effect as invoking
             * {@code new String(encode(src), StandardCharsets.ISO_8859_1)}.
             *
             * @param   src
             *          the byte array to encode
             * @return  A String containing the resulting Base64 encoded characters
             */
            @SuppressWarnings("deprecation")
            public String encodeToString(byte[] src) {
                byte[] encoded = encode(src);
                return new String(encoded, 0, 0, encoded.length);
            }
    
            /**
             * Encodes all remaining bytes from the specified byte buffer into
             * a newly-allocated ByteBuffer using the {@link Base64} encoding
             * scheme.
             *
             * Upon return, the source buffer's position will be updated to
             * its limit; its limit will not have been changed. The returned
             * output buffer's position will be zero and its limit will be the
             * number of resulting encoded bytes.
             *
             * @param   buffer
             *          the source ByteBuffer to encode
             * @return  A newly-allocated byte buffer containing the encoded bytes.
             */
            public ByteBuffer encode(ByteBuffer buffer) {
                int len = outLength(buffer.remaining());
                byte[] dst = new byte[len];
                int ret = 0;
                if (buffer.hasArray()) {
                    ret = encode0(buffer.array(),
                                  buffer.arrayOffset() + buffer.position(),
                                  buffer.arrayOffset() + buffer.limit(),
                                  dst);
                    buffer.position(buffer.limit());
                } else {
                    byte[] src = new byte[buffer.remaining()];
                    buffer.get(src);
                    ret = encode0(src, 0, src.length, dst);
                }
                if (ret != dst.length)
                     dst = Arrays.copyOf(dst, ret);
                return ByteBuffer.wrap(dst);
            }
    
            /**
             * Wraps an output stream for encoding byte data using the {@link Base64}
             * encoding scheme.
             *
             * <p> It is recommended to promptly close the returned output stream after
             * use, during which it will flush all possible leftover bytes to the underlying
             * output stream. Closing the returned output stream will close the underlying
             * output stream.
             *
             * @param   os
             *          the output stream.
             * @return  the output stream for encoding the byte data into the
             *          specified Base64 encoded format
             */
            public OutputStream wrap(OutputStream os) {
                Objects.requireNonNull(os);
                return new EncOutputStream(os, isURL ? toBase64URL : toBase64,
                                           newline, linemax, doPadding);
            }
    
            /**
             * Returns an encoder instance that encodes equivalently to this one,
             * but without adding any padding character at the end of the encoded
             * byte data.
             *
             * <p> The encoding scheme of this encoder instance is unaffected by
             * this invocation. The returned encoder instance should be used for
             * non-padding encoding operation.
             *
             * @return an equivalent encoder that encodes without adding any
             *         padding character at the end
             */
            public Encoder withoutPadding() {
                if (!doPadding)
                    return this;
                return new Encoder(isURL, newline, linemax, false);
            }
    
            private int encode0(byte[] src, int off, int end, byte[] dst) {
                char[] base64 = isURL ? toBase64URL : toBase64;
                int sp = off;
                int slen = (end - off) / 3 * 3;
                int sl = off + slen;
                if (linemax > 0 && slen  > linemax / 4 * 3)
                    slen = linemax / 4 * 3;
                int dp = 0;
                while (sp < sl) {
                    int sl0 = Math.min(sp + slen, sl);
                    for (int sp0 = sp, dp0 = dp ; sp0 < sl0; ) {
                        int bits = (src[sp0++] & 0xff) << 16 |
                                   (src[sp0++] & 0xff) <<  8 |
                                   (src[sp0++] & 0xff);
                        dst[dp0++] = (byte)base64[(bits >>> 18) & 0x3f];
                        dst[dp0++] = (byte)base64[(bits >>> 12) & 0x3f];
                        dst[dp0++] = (byte)base64[(bits >>> 6)  & 0x3f];
                        dst[dp0++] = (byte)base64[bits & 0x3f];
                    }
                    int dlen = (sl0 - sp) / 3 * 4;
                    dp += dlen;
                    sp = sl0;
                    if (dlen == linemax && sp < end) {
                        for (byte b : newline){
                            dst[dp++] = b;
                        }
                    }
                }
                if (sp < end) {               // 1 or 2 leftover bytes
                    int b0 = src[sp++] & 0xff;
                    dst[dp++] = (byte)base64[b0 >> 2];
                    if (sp == end) {
                        dst[dp++] = (byte)base64[(b0 << 4) & 0x3f];
                        if (doPadding) {
                            dst[dp++] = '=';
                            dst[dp++] = '=';
                        }
                    } else {
                        int b1 = src[sp++] & 0xff;
                        dst[dp++] = (byte)base64[(b0 << 4) & 0x3f | (b1 >> 4)];
                        dst[dp++] = (byte)base64[(b1 << 2) & 0x3f];
                        if (doPadding) {
                            dst[dp++] = '=';
                        }
                    }
                }
                return dp;
            }
        }
    
        /**
         * This class implements a decoder for decoding byte data using the
         * Base64 encoding scheme as specified in RFC 4648 and RFC 2045.
         *
         * <p> The Base64 padding character {@code '='} is accepted and
         * interpreted as the end of the encoded byte data, but is not
         * required. So if the final unit of the encoded byte data only has
         * two or three Base64 characters (without the corresponding padding
         * character(s) padded), they are decoded as if followed by padding
         * character(s). If there is a padding character present in the
         * final unit, the correct number of padding character(s) must be
         * present, otherwise {@code IllegalArgumentException} (
         * {@code IOException} when reading from a Base64 stream) is thrown
         * during decoding.
         *
         * <p> Instances of {@link Decoder} class are safe for use by
         * multiple concurrent threads.
         *
         * <p> Unless otherwise noted, passing a {@code null} argument to
         * a method of this class will cause a
         * {@link java.lang.NullPointerException NullPointerException} to
         * be thrown.
         *
         * @see     Encoder
         * @since   1.8
         */
        public static class Decoder {
    
            private final boolean isURL;
            private final boolean isMIME;
    
            private Decoder(boolean isURL, boolean isMIME) {
                this.isURL = isURL;
                this.isMIME = isMIME;
            }
    
            /**
             * Lookup table for decoding unicode characters drawn from the
             * "Base64 Alphabet" (as specified in Table 1 of RFC 2045) into
             * their 6-bit positive integer equivalents.  Characters that
             * are not in the Base64 alphabet but fall within the bounds of
             * the array are encoded to -1.
             *
             */
            private static final int[] fromBase64 = new int[256];
            static {
                Arrays.fill(fromBase64, -1);
                for (int i = 0; i < Encoder.toBase64.length; i++)
                    fromBase64[Encoder.toBase64[i]] = i;
                fromBase64['='] = -2;
            }
    
            /**
             * Lookup table for decoding "URL and Filename safe Base64 Alphabet"
             * as specified in Table2 of the RFC 4648.
             */
            private static final int[] fromBase64URL = new int[256];
    
            static {
                Arrays.fill(fromBase64URL, -1);
                for (int i = 0; i < Encoder.toBase64URL.length; i++)
                    fromBase64URL[Encoder.toBase64URL[i]] = i;
                fromBase64URL['='] = -2;
            }
    
            static final Decoder RFC4648         = new Decoder(false, false);
            static final Decoder RFC4648_URLSAFE = new Decoder(true, false);
            static final Decoder RFC2045         = new Decoder(false, true);
    
            /**
             * Decodes all bytes from the input byte array using the {@link Base64}
             * encoding scheme, writing the results into a newly-allocated output
             * byte array. The returned byte array is of the length of the resulting
             * bytes.
             *
             * @param   src
             *          the byte array to decode
             *
             * @return  A newly-allocated byte array containing the decoded bytes.
             *
             * @throws  IllegalArgumentException
             *          if {@code src} is not in valid Base64 scheme
             */
            public byte[] decode(byte[] src) {
                byte[] dst = new byte[outLength(src, 0, src.length)];
                int ret = decode0(src, 0, src.length, dst);
                if (ret != dst.length) {
                    dst = Arrays.copyOf(dst, ret);
                }
                return dst;
            }
    
            /**
             * Decodes a Base64 encoded String into a newly-allocated byte array
             * using the {@link Base64} encoding scheme.
             *
             * <p> An invocation of this method has exactly the same effect as invoking
             * {@code decode(src.getBytes(StandardCharsets.ISO_8859_1))}
             *
             * @param   src
             *          the string to decode
             *
             * @return  A newly-allocated byte array containing the decoded bytes.
             *
             * @throws  IllegalArgumentException
             *          if {@code src} is not in valid Base64 scheme
             */
            public byte[] decode(String src) {
                return decode(src.getBytes(StandardCharsets.ISO_8859_1));
            }
    
            /**
             * Decodes all bytes from the input byte array using the {@link Base64}
             * encoding scheme, writing the results into the given output byte array,
             * starting at offset 0.
             *
             * <p> It is the responsibility of the invoker of this method to make
             * sure the output byte array {@code dst} has enough space for decoding
             * all bytes from the input byte array. No bytes will be be written to
             * the output byte array if the output byte array is not big enough.
             *
             * <p> If the input byte array is not in valid Base64 encoding scheme
             * then some bytes may have been written to the output byte array before
             * IllegalargumentException is thrown.
             *
             * @param   src
             *          the byte array to decode
             * @param   dst
             *          the output byte array
             *
             * @return  The number of bytes written to the output byte array
             *
             * @throws  IllegalArgumentException
             *          if {@code src} is not in valid Base64 scheme, or {@code dst}
             *          does not have enough space for decoding all input bytes.
             */
            public int decode(byte[] src, byte[] dst) {
                int len = outLength(src, 0, src.length);
                if (dst.length < len)
                    throw new IllegalArgumentException(
                        "Output byte array is too small for decoding all input bytes");
                return decode0(src, 0, src.length, dst);
            }
    
            /**
             * Decodes all bytes from the input byte buffer using the {@link Base64}
             * encoding scheme, writing the results into a newly-allocated ByteBuffer.
             *
             * <p> Upon return, the source buffer's position will be updated to
             * its limit; its limit will not have been changed. The returned
             * output buffer's position will be zero and its limit will be the
             * number of resulting decoded bytes
             *
             * <p> {@code IllegalArgumentException} is thrown if the input buffer
             * is not in valid Base64 encoding scheme. The position of the input
             * buffer will not be advanced in this case.
             *
             * @param   buffer
             *          the ByteBuffer to decode
             *
             * @return  A newly-allocated byte buffer containing the decoded bytes
             *
             * @throws  IllegalArgumentException
             *          if {@code src} is not in valid Base64 scheme.
             */
            public ByteBuffer decode(ByteBuffer buffer) {
                int pos0 = buffer.position();
                try {
                    byte[] src;
                    int sp, sl;
                    if (buffer.hasArray()) {
                        src = buffer.array();
                        sp = buffer.arrayOffset() + buffer.position();
                        sl = buffer.arrayOffset() + buffer.limit();
                        buffer.position(buffer.limit());
                    } else {
                        src = new byte[buffer.remaining()];
                        buffer.get(src);
                        sp = 0;
                        sl = src.length;
                    }
                    byte[] dst = new byte[outLength(src, sp, sl)];
                    return ByteBuffer.wrap(dst, 0, decode0(src, sp, sl, dst));
                } catch (IllegalArgumentException iae) {
                    buffer.position(pos0);
                    throw iae;
                }
            }
    
            /**
             * Returns an input stream for decoding {@link Base64} encoded byte stream.
             *
             * <p> The {@code read}  methods of the returned {@code InputStream} will
             * throw {@code IOException} when reading bytes that cannot be decoded.
             *
             * <p> Closing the returned input stream will close the underlying
             * input stream.
             *
             * @param   is
             *          the input stream
             *
             * @return  the input stream for decoding the specified Base64 encoded
             *          byte stream
             */
            public InputStream wrap(InputStream is) {
                Objects.requireNonNull(is);
                return new DecInputStream(is, isURL ? fromBase64URL : fromBase64, isMIME);
            }
    
            private int outLength(byte[] src, int sp, int sl) {
                int[] base64 = isURL ? fromBase64URL : fromBase64;
                int paddings = 0;
                int len = sl - sp;
                if (len == 0)
                    return 0;
                if (len < 2) {
                    if (isMIME && base64[0] == -1)
                        return 0;
                    throw new IllegalArgumentException(
                        "Input byte[] should at least have 2 bytes for base64 bytes");
                }
                if (isMIME) {
                    // scan all bytes to fill out all non-alphabet. a performance
                    // trade-off of pre-scan or Arrays.copyOf
                    int n = 0;
                    while (sp < sl) {
                        int b = src[sp++] & 0xff;
                        if (b == '=') {
                            len -= (sl - sp + 1);
                            break;
                        }
                        if ((b = base64[b]) == -1)
                            n++;
                    }
                    len -= n;
                } else {
                    if (src[sl - 1] == '=') {
                        paddings++;
                        if (src[sl - 2] == '=')
                            paddings++;
                    }
                }
                if (paddings == 0 && (len & 0x3) !=  0)
                    paddings = 4 - (len & 0x3);
                return 3 * ((len + 3) / 4) - paddings;
            }
    
            private int decode0(byte[] src, int sp, int sl, byte[] dst) {
                int[] base64 = isURL ? fromBase64URL : fromBase64;
                int dp = 0;
                int bits = 0;
                int shiftto = 18;       // pos of first byte of 4-byte atom
                while (sp < sl) {
                    int b = src[sp++] & 0xff;
                    if ((b = base64[b]) < 0) {
                        if (b == -2) {         // padding byte '='
                            // =     shiftto==18 unnecessary padding
                            // x=    shiftto==12 a dangling single x
                            // x     to be handled together with non-padding case
                            // xx=   shiftto==6&&sp==sl missing last =
                            // xx=y  shiftto==6 last is not =
                            if (shiftto == 6 && (sp == sl || src[sp++] != '=') ||
                                shiftto == 18) {
                                throw new IllegalArgumentException(
                                    "Input byte array has wrong 4-byte ending unit");
                            }
                            break;
                        }
                        if (isMIME)    // skip if for rfc2045
                            continue;
                        else
                            throw new IllegalArgumentException(
                                "Illegal base64 character " +
                                Integer.toString(src[sp - 1], 16));
                    }
                    bits |= (b << shiftto);
                    shiftto -= 6;
                    if (shiftto < 0) {
                        dst[dp++] = (byte)(bits >> 16);
                        dst[dp++] = (byte)(bits >>  8);
                        dst[dp++] = (byte)(bits);
                        shiftto = 18;
                        bits = 0;
                    }
                }
                // reached end of byte array or hit padding '=' characters.
                if (shiftto == 6) {
                    dst[dp++] = (byte)(bits >> 16);
                } else if (shiftto == 0) {
                    dst[dp++] = (byte)(bits >> 16);
                    dst[dp++] = (byte)(bits >>  8);
                } else if (shiftto == 12) {
                    // dangling single "x", incorrectly encoded.
                    throw new IllegalArgumentException(
                        "Last unit does not have enough valid bits");
                }
                // anything left is invalid, if is not MIME.
                // if MIME, ignore all non-base64 character
                while (sp < sl) {
                    if (isMIME && base64[src[sp++]] < 0)
                        continue;
                    throw new IllegalArgumentException(
                        "Input byte array has incorrect ending byte at " + sp);
                }
                return dp;
            }
        }
    
        /*
         * An output stream for encoding bytes into the Base64.
         */
        private static class EncOutputStream extends FilterOutputStream {
    
            private int leftover = 0;
            private int b0, b1, b2;
            private boolean closed = false;
    
            private final char[] base64;    // byte->base64 mapping
            private final byte[] newline;   // line separator, if needed
            private final int linemax;
            private final boolean doPadding;// whether or not to pad
            private int linepos = 0;
    
            EncOutputStream(OutputStream os, char[] base64,
                            byte[] newline, int linemax, boolean doPadding) {
                super(os);
                this.base64 = base64;
                this.newline = newline;
                this.linemax = linemax;
                this.doPadding = doPadding;
            }
    
            @Override
            public void write(int b) throws IOException {
                byte[] buf = new byte[1];
                buf[0] = (byte)(b & 0xff);
                write(buf, 0, 1);
            }
    
            private void checkNewline() throws IOException {
                if (linepos == linemax) {
                    out.write(newline);
                    linepos = 0;
                }
            }
    
            @Override
            public void write(byte[] b, int off, int len) throws IOException {
                if (closed)
                    throw new IOException("Stream is closed");
                if (off < 0 || len < 0 || off + len > b.length)
                    throw new ArrayIndexOutOfBoundsException();
                if (len == 0)
                    return;
                if (leftover != 0) {
                    if (leftover == 1) {
                        b1 = b[off++] & 0xff;
                        len--;
                        if (len == 0) {
                            leftover++;
                            return;
                        }
                    }
                    b2 = b[off++] & 0xff;
                    len--;
                    checkNewline();
                    out.write(base64[b0 >> 2]);
                    out.write(base64[(b0 << 4) & 0x3f | (b1 >> 4)]);
                    out.write(base64[(b1 << 2) & 0x3f | (b2 >> 6)]);
                    out.write(base64[b2 & 0x3f]);
                    linepos += 4;
                }
                int nBits24 = len / 3;
                leftover = len - (nBits24 * 3);
                while (nBits24-- > 0) {
                    checkNewline();
                    int bits = (b[off++] & 0xff) << 16 |
                               (b[off++] & 0xff) <<  8 |
                               (b[off++] & 0xff);
                    out.write(base64[(bits >>> 18) & 0x3f]);
                    out.write(base64[(bits >>> 12) & 0x3f]);
                    out.write(base64[(bits >>> 6)  & 0x3f]);
                    out.write(base64[bits & 0x3f]);
                    linepos += 4;
               }
                if (leftover == 1) {
                    b0 = b[off++] & 0xff;
                } else if (leftover == 2) {
                    b0 = b[off++] & 0xff;
                    b1 = b[off++] & 0xff;
                }
            }
    
            @Override
            public void close() throws IOException {
                if (!closed) {
                    closed = true;
                    if (leftover == 1) {
                        checkNewline();
                        out.write(base64[b0 >> 2]);
                        out.write(base64[(b0 << 4) & 0x3f]);
                        if (doPadding) {
                            out.write('=');
                            out.write('=');
                        }
                    } else if (leftover == 2) {
                        checkNewline();
                        out.write(base64[b0 >> 2]);
                        out.write(base64[(b0 << 4) & 0x3f | (b1 >> 4)]);
                        out.write(base64[(b1 << 2) & 0x3f]);
                        if (doPadding) {
                           out.write('=');
                        }
                    }
                    leftover = 0;
                    out.close();
                }
            }
        }
    
        /*
         * An input stream for decoding Base64 bytes
         */
        private static class DecInputStream extends InputStream {
    
            private final InputStream is;
            private final boolean isMIME;
            private final int[] base64;      // base64 -> byte mapping
            private int bits = 0;            // 24-bit buffer for decoding
            private int nextin = 18;         // next available "off" in "bits" for input;
                                             // -> 18, 12, 6, 0
            private int nextout = -8;        // next available "off" in "bits" for output;
                                             // -> 8, 0, -8 (no byte for output)
            private boolean eof = false;
            private boolean closed = false;
    
            DecInputStream(InputStream is, int[] base64, boolean isMIME) {
                this.is = is;
                this.base64 = base64;
                this.isMIME = isMIME;
            }
    
            private byte[] sbBuf = new byte[1];
    
            @Override
            public int read() throws IOException {
                return read(sbBuf, 0, 1) == -1 ? -1 : sbBuf[0] & 0xff;
            }
    
            @Override
            public int read(byte[] b, int off, int len) throws IOException {
                if (closed)
                    throw new IOException("Stream is closed");
                if (eof && nextout < 0)    // eof and no leftover
                    return -1;
                if (off < 0 || len < 0 || len > b.length - off)
                    throw new IndexOutOfBoundsException();
                int oldOff = off;
                if (nextout >= 0) {       // leftover output byte(s) in bits buf
                    do {
                        if (len == 0)
                            return off - oldOff;
                        b[off++] = (byte)(bits >> nextout);
                        len--;
                        nextout -= 8;
                    } while (nextout >= 0);
                    bits = 0;
                }
                while (len > 0) {
                    int v = is.read();
                    if (v == -1) {
                        eof = true;
                        if (nextin != 18) {
                            if (nextin == 12)
                                throw new IOException("Base64 stream has one un-decoded dangling byte.");
                            // treat ending xx/xxx without padding character legal.
                            // same logic as v == '=' below
                            b[off++] = (byte)(bits >> (16));
                            len--;
                            if (nextin == 0) {           // only one padding byte
                                if (len == 0) {          // no enough output space
                                    bits >>= 8;          // shift to lowest byte
                                    nextout = 0;
                                } else {
                                    b[off++] = (byte) (bits >>  8);
                                }
                            }
                        }
                        if (off == oldOff)
                            return -1;
                        else
                            return off - oldOff;
                    }
                    if (v == '=') {                  // padding byte(s)
                        // =     shiftto==18 unnecessary padding
                        // x=    shiftto==12 dangling x, invalid unit
                        // xx=   shiftto==6 && missing last '='
                        // xx=y  or last is not '='
                        if (nextin == 18 || nextin == 12 ||
                            nextin == 6 && is.read() != '=') {
                            throw new IOException("Illegal base64 ending sequence:" + nextin);
                        }
                        b[off++] = (byte)(bits >> (16));
                        len--;
                        if (nextin == 0) {           // only one padding byte
                            if (len == 0) {          // no enough output space
                                bits >>= 8;          // shift to lowest byte
                                nextout = 0;
                            } else {
                                b[off++] = (byte) (bits >>  8);
                            }
                        }
                        eof = true;
                        break;
                    }
                    if ((v = base64[v]) == -1) {
                        if (isMIME)                 // skip if for rfc2045
                            continue;
                        else
                            throw new IOException("Illegal base64 character " +
                                Integer.toString(v, 16));
                    }
                    bits |= (v << nextin);
                    if (nextin == 0) {
                        nextin = 18;    // clear for next
                        nextout = 16;
                        while (nextout >= 0) {
                            b[off++] = (byte)(bits >> nextout);
                            len--;
                            nextout -= 8;
                            if (len == 0 && nextout >= 0) {  // don't clean "bits"
                                return off - oldOff;
                            }
                        }
                        bits = 0;
                    } else {
                        nextin -= 6;
                    }
                }
                return off - oldOff;
            }
    
            @Override
            public int available() throws IOException {
                if (closed)
                    throw new IOException("Stream is closed");
                return is.available();   // TBD:
            }
    
            @Override
            public void close() throws IOException {
                if (!closed) {
                    closed = true;
                    is.close();
                }
            }
        }
    }

    (2)Base64工具类:

    package com.shuilangyizu.logistics;
    
    /**
     * @Description: base64加密,解密工具类
     * @author: shuilangyizu
     * @date: 2021年07月28日 15:55
     */
    public class Base64Util {
        /**
         * base64加密
         * @param content 待加密内容
         * @return byte[]
         */
        public static byte[] base64Encrypt(final String content) {
            return Base64.getEncoder().encode(content.getBytes());
        }
    
        /**
         * base64解密
         * @param encoderContent 已加密内容
         * @return byte[]
         */
        public static byte[] base64Decrypt(final byte[] encoderContent) {
            return Base64.getDecoder().decode(encoderContent);
        }
    }

     (3)HexUtils类:

    /**
     * @Description: base64加密,解密工具类
     * @author: shuilangyizu
     * @date: 2021年07月28日 15:55
     */
    package com.shuilangyizu.logistics;
    
    public final class HexUtils {
     private static final StringManager sm = StringManager.getManager(HexUtils.class);
     private static final int[] DEC = new int[]{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1, -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 10, 11, 12, 13, 14, 15};
     private static final byte[] HEX = new byte[]{48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 97, 98, 99, 100, 101, 102};
     private static final char[] hex = "0123456789abcdef".toCharArray();
    
     public HexUtils() {
     }
    
     public static int getDec(int index) {
         try {
             return DEC[index - 48];
         } catch (ArrayIndexOutOfBoundsException var2) {
             return -1;
         }
     }
    
     public static byte getHex(int index) {
         return HEX[index];
     }
    
     public static String toHexString(byte[] bytes) {
         if (null == bytes) {
             return null;
         } else {
             StringBuilder sb = new StringBuilder(bytes.length << 1);
             byte[] var2 = bytes;
             int var3 = bytes.length;
    
             for(int var4 = 0; var4 < var3; ++var4) {
                 byte aByte = var2[var4];
                 sb.append(hex[(aByte & 240) >> 4]).append(hex[aByte & 15]);
             }
    
             return sb.toString();
         }
     }
    
     public static byte[] fromHexString(String input) {
         if (input == null) {
             return null;
         } else if ((input.length() & 1) == 1) {
             throw new IllegalArgumentException(sm.getString("hexUtils.fromHex.oddDigits"));
         } else {
             char[] inputChars = input.toCharArray();
             byte[] result = new byte[input.length() >> 1];
    
             for(int i = 0; i < result.length; ++i) {
                 int upperNibble = getDec(inputChars[2 * i]);
                 int lowerNibble = getDec(inputChars[2 * i + 1]);
                 if (upperNibble < 0 || lowerNibble < 0) {
                     throw new IllegalArgumentException(sm.getString("hexUtils.fromHex.nonHex"));
                 }
    
                 result[i] = (byte)((upperNibble << 4) + lowerNibble);
             }
    
             return result;
         }
     }
    }

    (4)StringManager类:

    /**
     * @Description: base64加密,解密工具类
     * @author: shuilangyizu
     * @date: 2021年07月28日 15:55
     */
    package com.shuilangyizu.logistics;
    
    import java.text.FieldPosition;
    import java.text.MessageFormat;
    import java.util.Enumeration;
    import java.util.Hashtable;
    import java.util.LinkedHashMap;
    import java.util.Locale;
    import java.util.Map;
    import java.util.MissingResourceException;
    import java.util.ResourceBundle;
    import java.util.Map.Entry;
    
    public class StringManager {
     private static int LOCALE_CACHE_SIZE = 10;
     private final ResourceBundle bundle;
     private final Locale locale;
     private static final Map<String, Map<Locale, StringManager>> managers = new Hashtable();
    
     private StringManager(String packageName, Locale locale) {
         String bundleName = packageName + ".LocalStrings";
         ResourceBundle bnd = null;
    
         try {
             if (locale.getLanguage().equals(Locale.ENGLISH.getLanguage())) {
                 locale = Locale.ROOT;
             }
    
             bnd = ResourceBundle.getBundle(bundleName, locale);
         } catch (MissingResourceException var9) {
             ClassLoader cl = Thread.currentThread().getContextClassLoader();
             if (cl != null) {
                 try {
                     bnd = ResourceBundle.getBundle(bundleName, locale, cl);
                 } catch (MissingResourceException var8) {
                 }
             }
         }
    
         this.bundle = bnd;
         if (this.bundle != null) {
             Locale bundleLocale = this.bundle.getLocale();
             if (bundleLocale.equals(Locale.ROOT)) {
                 this.locale = Locale.ENGLISH;
             } else {
                 this.locale = bundleLocale;
             }
         } else {
             this.locale = null;
         }
    
     }
    
     public String getString(String key) {
         String str;
         if (key == null) {
             str = "key may not have a null value";
             throw new IllegalArgumentException(str);
         } else {
             str = null;
    
             try {
                 if (this.bundle != null) {
                     str = this.bundle.getString(key);
                 }
             } catch (MissingResourceException var4) {
                 str = null;
             }
    
             return str;
         }
     }
    
     public String getString(String key, Object... args) {
         String value = this.getString(key);
         if (value == null) {
             value = key;
         }
    
         MessageFormat mf = new MessageFormat(value);
         mf.setLocale(this.locale);
         return mf.format(args, new StringBuffer(), (FieldPosition)null).toString();
     }
    
     public Locale getLocale() {
         return this.locale;
     }
    
     public static final StringManager getManager(Class<?> clazz) {
         return getManager(clazz.getPackage().getName());
     }
    
     public static final StringManager getManager(String packageName) {
         return getManager(packageName, Locale.getDefault());
     }
    
     public static final synchronized StringManager getManager(String packageName, Locale locale) {
         Map<Locale, StringManager> map = (Map)managers.get(packageName);
         if (map == null) {
             map = new LinkedHashMap<Locale, StringManager>(LOCALE_CACHE_SIZE, 1.0F, true) {
                 private static final long serialVersionUID = 1L;
    
                 protected boolean removeEldestEntry(Entry<Locale, StringManager> eldest) {
                     return this.size() > StringManager.LOCALE_CACHE_SIZE - 1;
                 }
             };
             managers.put(packageName, map);
         }
    
         StringManager mgr = (StringManager)((Map)map).get(locale);
         if (mgr == null) {
             mgr = new StringManager(packageName, locale);
             ((Map)map).put(locale, mgr);
         }
    
         return mgr;
     }
    
     public static StringManager getManager(String packageName, Enumeration<Locale> requestedLocales) {
         while(true) {
             if (requestedLocales.hasMoreElements()) {
                 Locale locale = (Locale)requestedLocales.nextElement();
                 StringManager result = getManager(packageName, locale);
                 if (!result.getLocale().equals(locale)) {
                     continue;
                 }
    
                 return result;
             }
    
             return getManager(packageName);
         }
     }
    }
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  • 原文地址:https://www.cnblogs.com/shuilangyizu/p/15071405.html
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