package org.bouncycastle.util.encoders;import java.io.ByteArrayOutputStream;import java.io.IOException;import java.io.OutputStream;/** * Convert binary data to and from UrlBase64 encoding.  This is identical to * Base64 encoding, except that the padding character is "." and the other  * non-alphanumeric characters are "-" and "_" instead of "+" and "/". * <p> * The purpose of UrlBase64 encoding is to provide a compact encoding of binary * data that is safe for use as an URL parameter. Base64 encoding does not * produce encoded values that are safe for use in URLs, since "/" can be  * interpreted as a path delimiter; "+" is the encoded form of a space; and * "=" is used to separate a name from the corresponding value in an URL  * parameter. */public class UrlBase64{    private static final Encoder encoder = new UrlBase64Encoder();        /**     * Encode the input data producing a URL safe base 64 encoded byte array.     *     * @return a byte array containing the URL safe base 64 encoded data.     */    public static byte[] encode(        byte[]    data)    {        ByteArrayOutputStream    bOut = new ByteArrayOutputStream();                try        {            encoder.encode(data, 0, data.length, bOut);        }        catch (IOException e)        {            throw new RuntimeException("exception encoding URL safe base64 string: " + e);        }                return bOut.toByteArray();    }    /**     * Encode the byte data writing it to the given output stream.     *     * @return the number of bytes produced.     */    public static int encode(        byte[]                data,        OutputStream    out)        throws IOException    {        return encoder.encode(data, 0, data.length, out);    }        /**     * Decode the URL safe base 64 encoded input data - white space will be ignored.     *     * @return a byte array representing the decoded data.     */    public static byte[] decode(        byte[]    data)    {        ByteArrayOutputStream    bOut = new ByteArrayOutputStream();                try        {            encoder.decode(data, 0, data.length, bOut);        }        catch (IOException e)        {            throw new RuntimeException("exception decoding URL safe base64 string: " + e);        }                return bOut.toByteArray();    }        /**     * decode the URL safe base 64 encoded byte data writing it to the given output stream,     * whitespace characters will be ignored.     *     * @return the number of bytes produced.     */    public static int decode(        byte[]                data,        OutputStream    out)        throws IOException    {        return encoder.decode(data, 0, data.length, out);    }        /**     * decode the URL safe base 64 encoded String data - whitespace will be ignored.     *     * @return a byte array representing the decoded data.     */    public static byte[] decode(        String    data)    {        ByteArrayOutputStream    bOut = new ByteArrayOutputStream();                try        {            encoder.decode(data, bOut);        }        catch (IOException e)        {            throw new RuntimeException("exception decoding URL safe base64 string: " + e);        }                return bOut.toByteArray();    }        /**     * Decode the URL safe base 64 encoded String data writing it to the given output stream,     * whitespace characters will be ignored.     *     * @return the number of bytes produced.     */    public static int decode(        String                data,        OutputStream    out)        throws IOException    {        return encoder.decode(data, out);    }}