Base32InputStream.java

/*
 * 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 org.apache.commons.codec.binary;

import java.io.InputStream;

/**
 * Provides Base32 encoding and decoding in a streaming fashion (unlimited
 * size). When encoding the default lineLength is 76 characters and the default
 * lineEnding is CRLF, but these can be overridden by using the appropriate
 * constructor.
 * <p>
 * The default behaviour of the Base32InputStream is to DECODE, whereas the
 * default behaviour of the Base32OutputStream is to ENCODE, but this behaviour
 * can be overridden by using a different constructor.
 * </p>
 * <p>
 * Since this class operates directly on byte streams, and not character
 * streams, it is hard-coded to only encode/decode character encodings which are
 * compatible with the lower 127 ASCII chart (ISO-8859-1, Windows-1252, UTF-8,
 * etc).
 * </p>
 * 
 * @version $Id: Base32InputStream.java 1376694 2012-08-23 20:55:04Z tn $
 * @see <a href="http://www.ietf.org/rfc/rfc4648.txt">RFC 4648</a>
 * @since 1.5
 */
public class Base32InputStream extends BaseNCodecInputStream {

	/**
	 * Creates a Base32InputStream such that all data read is Base32-decoded
	 * from the original provided InputStream.
	 * 
	 * @param in
	 *            InputStream to wrap.
	 */
	public Base32InputStream(InputStream in) {
		this(in, false);
	}

	/**
	 * Creates a Base32InputStream such that all data read is either
	 * Base32-encoded or Base32-decoded from the original provided InputStream.
	 * 
	 * @param in
	 *            InputStream to wrap.
	 * @param doEncode
	 *            true if we should encode all data read from us, false if we
	 *            should decode.
	 */
	public Base32InputStream(InputStream in, boolean doEncode) {
		super(in, new Base32(false), doEncode);
	}

	/**
	 * Creates a Base32InputStream such that all data read is either
	 * Base32-encoded or Base32-decoded from the original provided InputStream.
	 * 
	 * @param in
	 *            InputStream to wrap.
	 * @param doEncode
	 *            true if we should encode all data read from us, false if we
	 *            should decode.
	 * @param lineLength
	 *            If doEncode is true, each line of encoded data will contain
	 *            lineLength characters (rounded down to nearest multiple of 4).
	 *            If lineLength <=0, the encoded data is not divided into lines.
	 *            If doEncode is false, lineLength is ignored.
	 * @param lineSeparator
	 *            If doEncode is true, each line of encoded data will be
	 *            terminated with this byte sequence (e.g. \r\n). If lineLength
	 *            <= 0, the lineSeparator is not used. If doEncode is false
	 *            lineSeparator is ignored.
	 */
	public Base32InputStream(InputStream in, boolean doEncode, int lineLength,
			byte[] lineSeparator) {
		super(in, new Base32(lineLength, lineSeparator), doEncode);
	}

}