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1905 chandransh 1 
package in.shop2020.serving.utils.ebs;
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import java.io.ByteArrayOutputStream;
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/**
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 * This class contains two static methods for Base64 encoding and decoding.
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 *
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 * @author <a href="http://izhuk.com">Igor Zhukovsky</a>
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 */
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public class Base64 {
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	final static String base64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
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	/**
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	 * Decodes BASE64 encoded string.
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	 *
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	 * @param encoded
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	 *            The BASE64 encoded string to be decoded
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	 * @return decoded data as byte array
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	 */
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	public byte[] decode(String encoded) {
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		int i;
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		byte output[] = new byte[3];
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		int state;
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		ByteArrayOutputStream data = new ByteArrayOutputStream(encoded.length());
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		state = 1;
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		for (i = 0; i < encoded.length(); i++) {
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			byte c;
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			{
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				char alpha = encoded.charAt(i);
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				if (Character.isWhitespace(alpha))
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					continue;
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				if ((alpha >= 'A') && (alpha <= 'Z'))
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					c = (byte) (alpha - 'A');
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				else if ((alpha >= 'a') && (alpha <= 'z'))
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					c = (byte) (26 + (alpha - 'a'));
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				else if ((alpha >= '0') && (alpha <= '9'))
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					c = (byte) (52 + (alpha - '0'));
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				else if (alpha == '+')
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					c = 62;
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				else if (alpha == '/')
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					c = 63;
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				else if (alpha == '=')
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					break; // end
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				else
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					return null; // error
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			}
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			switch (state) {
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			case 1:
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				output[0] = (byte) (c << 2);
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				break;
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			case 2:
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				output[0] |= (byte) (c >>> 4);
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				output[1] = (byte) ((c & 0x0F) << 4);
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				break;
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			case 3:
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				output[1] |= (byte) (c >>> 2);
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				output[2] = (byte) ((c & 0x03) << 6);
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				break;
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			case 4:
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				output[2] |= c;
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				data.write(output, 0, output.length);
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				break;
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			}
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			state = (state < 4 ? state + 1 : 1);
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		} // for
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		if (i < encoded.length()) /* then '=' found, but the end of string */
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			switch (state) {
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			case 3:
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				data.write(output, 0, 1);
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				return (encoded.charAt(i) == '=')
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						&& (encoded.charAt(i + 1) == '=') ? data.toByteArray()
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						: null;
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			case 4:
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				data.write(output, 0, 2);
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				return (encoded.charAt(i) == '=') ? data.toByteArray() : null;
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			default:
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				return null;
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			}
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		else
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			return (state == 1 ? data.toByteArray() : null); /* end of string */
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	} // decode
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	/**
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	 * Encodes binary data by BASE64 method.
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	 *
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	 * @param data
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	 *            binary data as byte array
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	 * @return encoded data as String
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	 */
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	public String encode(byte[] data) {
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		char output[] = new char[4];
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		int state = 1;
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		int restbits = 0;
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		int chunks = 0;
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		StringBuffer encoded = new StringBuffer();
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		for (int i = 0; i < data.length; i++) {
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			int ic = (data[i] >= 0 ? data[i] : (data[i] & 0x7F) + 128);
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			switch (state) {
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			case 1:
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				output[0] = base64.charAt(ic >>> 2);
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				restbits = ic & 0x03;
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				break;
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			case 2:
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				output[1] = base64.charAt((restbits << 4) | (ic >>> 4));
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				restbits = ic & 0x0F;
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				break;
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			case 3:
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				output[2] = base64.charAt((restbits << 2) | (ic >>> 6));
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				output[3] = base64.charAt(ic & 0x3F);
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				encoded.append(output);
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				// keep no more than 76 character per line
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				chunks++;
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				if ((chunks % 19) == 0)
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					encoded.append("\r\n");
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				break;
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			}
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			state = (state < 3 ? state + 1 : 1);
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		} // for
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		/* final */
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		switch (state) {
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		case 2:
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			output[1] = base64.charAt((restbits << 4));
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			output[2] = output[3] = '=';
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			encoded.append(output);
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			break;
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		case 3:
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			output[2] = base64.charAt((restbits << 2));
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			output[3] = '=';
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			encoded.append(output);
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			break;
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		}
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		return encoded.toString();
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	}
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}