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A strong typed high performance Java Template engine with .Net Razor like syntax
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/* 
 * Copyright (C) 2013 The Rythm Engine project
 * Gelin Luo 
 *
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
*/
package com.greenlaw110.rythm.sandbox;

/**
 * Source code come from 
 * http://www.source-code.biz/base64coder/java/Base64Coder.java.txt,
 * 
 * Under Apache License, V2.0
 */
class Base64 {

    // The line separator string of the operating system.
    private static final String systemLineSeparator = System.getProperty("line.separator");

    // Mapping table from 6-bit nibbles to Base64 characters.
    private static final char[] map1 = new char[64];

    static {
        int i = 0;
        for (char c = 'A'; c <= 'Z'; c++) map1[i++] = c;
        for (char c = 'a'; c <= 'z'; c++) map1[i++] = c;
        for (char c = '0'; c <= '9'; c++) map1[i++] = c;
        map1[i++] = '+';
        map1[i++] = '/';
    }

    // Mapping table from Base64 characters to 6-bit nibbles.
    private static final byte[] map2 = new byte[128];

    static {
        for (int i = 0; i < map2.length; i++) map2[i] = -1;
        for (int i = 0; i < 64; i++) map2[map1[i]] = (byte) i;
    }

    /**
     * Encodes a byte array into Base64 format.
     * No blanks or line breaks are inserted in the output.
     *
     * @param in An array containing the data bytes to be encoded.
     * @return A character array containing the Base64 encoded data.
     */
    public static char[] encode(byte[] in) {
        return encode(in, 0, in.length);
    }


    /**
     * Encodes a byte array into Base64 format.
     * No blanks or line breaks are inserted in the output.
     *
     * @param in   An array containing the data bytes to be encoded.
     * @param iOff Offset of the first byte in in to be processed.
     * @param iLen Number of bytes to process in in, starting at iOff.
     * @return A character array containing the Base64 encoded data.
     */
    public static char[] encode(byte[] in, int iOff, int iLen) {
        int oDataLen = (iLen * 4 + 2) / 3;       // output length without padding
        int oLen = ((iLen + 2) / 3) * 4;         // output length including padding
        char[] out = new char[oLen];
        int ip = iOff;
        int iEnd = iOff + iLen;
        int op = 0;
        while (ip < iEnd) {
            int i0 = in[ip++] & 0xff;
            int i1 = ip < iEnd ? in[ip++] & 0xff : 0;
            int i2 = ip < iEnd ? in[ip++] & 0xff : 0;
            int o0 = i0 >>> 2;
            int o1 = ((i0 & 3) << 4) | (i1 >>> 4);
            int o2 = ((i1 & 0xf) << 2) | (i2 >>> 6);
            int o3 = i2 & 0x3F;
            out[op++] = map1[o0];
            out[op++] = map1[o1];
            out[op] = op < oDataLen ? map1[o2] : '=';
            op++;
            out[op] = op < oDataLen ? map1[o3] : '=';
            op++;
        }
        return out;
    }

}