1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/net/fortuna/ical4j/data/UnfoldingReader.java Tue Feb 10 18:12:00 2015 +0100
1.3 @@ -0,0 +1,239 @@
1.4 +/**
1.5 + * Copyright (c) 2012, Ben Fortuna
1.6 + * All rights reserved.
1.7 + *
1.8 + * Redistribution and use in source and binary forms, with or without
1.9 + * modification, are permitted provided that the following conditions
1.10 + * are met:
1.11 + *
1.12 + * o Redistributions of source code must retain the above copyright
1.13 + * notice, this list of conditions and the following disclaimer.
1.14 + *
1.15 + * o Redistributions in binary form must reproduce the above copyright
1.16 + * notice, this list of conditions and the following disclaimer in the
1.17 + * documentation and/or other materials provided with the distribution.
1.18 + *
1.19 + * o Neither the name of Ben Fortuna nor the names of any other contributors
1.20 + * may be used to endorse or promote products derived from this software
1.21 + * without specific prior written permission.
1.22 + *
1.23 + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
1.24 + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
1.25 + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
1.26 + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
1.27 + * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
1.28 + * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
1.29 + * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
1.30 + * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
1.31 + * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
1.32 + * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
1.33 + * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.34 + */
1.35 +package net.fortuna.ical4j.data;
1.36 +
1.37 +import java.io.IOException;
1.38 +import java.io.PushbackReader;
1.39 +import java.io.Reader;
1.40 +import java.util.Arrays;
1.41 +
1.42 +import net.fortuna.ical4j.util.CompatibilityHints;
1.43 +
1.44 +import org.apache.commons.logging.Log;
1.45 +import org.apache.commons.logging.LogFactory;
1.46 +
1.47 +/**
1.48 + * <pre>
1.49 + * $Id$ [06-Apr-2004]
1.50 + * </pre>
1.51 + *
1.52 + * A reader which performs iCalendar unfolding as it reads. Note that unfolding rules may be "relaxed" to allow
1.53 + * unfolding of non-conformant *.ics files. By specifying the system property "ical4j.unfolding.relaxed=true" iCalendar
1.54 + * files created with Mozilla Calendar/Sunbird may be correctly unfolded.
1.55 + *
1.56 + * To wrap this reader with a {@link java.io.BufferedReader} you must ensure you specify an identical buffer size
1.57 + * to that used in the {@link java.io.BufferedReader}.
1.58 + *
1.59 + * @author Ben Fortuna
1.60 + */
1.61 +public class UnfoldingReader extends PushbackReader {
1.62 +
1.63 + private Log log = LogFactory.getLog(UnfoldingReader.class);
1.64 +
1.65 + /**
1.66 + * The pattern used to identify a fold in an iCalendar data stream.
1.67 + */
1.68 + private static final char[] DEFAULT_FOLD_PATTERN_1 = { '\r', '\n', ' ' };
1.69 +
1.70 + /**
1.71 + * The pattern used to identify a fold in Microsoft Outlook 2007.
1.72 + */
1.73 + private static final char[] DEFAULT_FOLD_PATTERN_2 = { '\r', '\n', '\t' };
1.74 +
1.75 + /**
1.76 + * The pattern used to identify a fold in Mozilla Calendar/Sunbird and KOrganizer.
1.77 + */
1.78 + private static final char[] RELAXED_FOLD_PATTERN_1 = { '\n', ' ' };
1.79 +
1.80 + /**
1.81 + * The pattern used to identify a fold in Microsoft Outlook 2007.
1.82 + */
1.83 + private static final char[] RELAXED_FOLD_PATTERN_2 = { '\n', '\t' };
1.84 +
1.85 + private char[][] patterns;
1.86 +
1.87 + private char[][] buffers;
1.88 +
1.89 + private int linesUnfolded;
1.90 +
1.91 + private int maxPatternLength = 0;
1.92 +
1.93 + /**
1.94 + * Creates a new unfolding reader instance. Relaxed unfolding flag is read from system property.
1.95 + * @param in the reader to unfold from
1.96 + */
1.97 + public UnfoldingReader(final Reader in) {
1.98 + this(in, DEFAULT_FOLD_PATTERN_1.length, CompatibilityHints
1.99 + .isHintEnabled(CompatibilityHints.KEY_RELAXED_UNFOLDING));
1.100 + }
1.101 +
1.102 + /**
1.103 + * @param in reader source for data
1.104 + * @param size the buffer size
1.105 + */
1.106 + public UnfoldingReader(final Reader in, int size) {
1.107 + this(in, size, CompatibilityHints.isHintEnabled(CompatibilityHints.KEY_RELAXED_UNFOLDING));
1.108 + }
1.109 +
1.110 + /**
1.111 + * @param in reader source for data
1.112 + * @param relaxed indicates whether relaxed unfolding is enabled
1.113 + */
1.114 + public UnfoldingReader(final Reader in, boolean relaxed) {
1.115 + this(in, DEFAULT_FOLD_PATTERN_1.length, relaxed);
1.116 + }
1.117 +
1.118 + /**
1.119 + * Creates a new unfolding reader instance.
1.120 + * @param in a reader to read from
1.121 + * @param size the buffer size
1.122 + * @param relaxed specifies whether unfolding is relaxed
1.123 + */
1.124 + public UnfoldingReader(final Reader in, int size, final boolean relaxed) {
1.125 + super(in, size);
1.126 + if (relaxed) {
1.127 + patterns = new char[4][];
1.128 + patterns[0] = DEFAULT_FOLD_PATTERN_1;
1.129 + patterns[1] = DEFAULT_FOLD_PATTERN_2;
1.130 + patterns[2] = RELAXED_FOLD_PATTERN_1;
1.131 + patterns[3] = RELAXED_FOLD_PATTERN_2;
1.132 + }
1.133 + else {
1.134 + patterns = new char[2][];
1.135 + patterns[0] = DEFAULT_FOLD_PATTERN_1;
1.136 + patterns[1] = DEFAULT_FOLD_PATTERN_2;
1.137 + }
1.138 + buffers = new char[patterns.length][];
1.139 + for (int i = 0; i < patterns.length; i++) {
1.140 + buffers[i] = new char[patterns[i].length];
1.141 + maxPatternLength = Math.max(maxPatternLength, patterns[i].length);
1.142 + }
1.143 + }
1.144 +
1.145 + /**
1.146 + * @return number of lines unfolded so far while reading
1.147 + */
1.148 + public final int getLinesUnfolded() {
1.149 + return linesUnfolded;
1.150 + }
1.151 +
1.152 + /**
1.153 + * {@inheritDoc}
1.154 + */
1.155 + public final int read() throws IOException {
1.156 + final int c = super.read();
1.157 + boolean doUnfold = false;
1.158 + for (int i = 0; i < patterns.length; i++) {
1.159 + if (c == patterns[i][0]) {
1.160 + doUnfold = true;
1.161 + break;
1.162 + }
1.163 + }
1.164 + if (!doUnfold) {
1.165 + return c;
1.166 + }
1.167 + else {
1.168 + unread(c);
1.169 + }
1.170 +
1.171 + unfold();
1.172 +
1.173 + return super.read();
1.174 + }
1.175 +
1.176 + /**
1.177 + * {@inheritDoc}
1.178 + */
1.179 + public int read(final char[] cbuf, final int off, final int len) throws IOException {
1.180 + final int read = super.read(cbuf, off, len);
1.181 + boolean doUnfold = false;
1.182 + for (int i = 0; i < patterns.length; i++) {
1.183 + if (read > 0 && cbuf[0] == patterns[i][0]) {
1.184 + doUnfold = true;
1.185 + break;
1.186 + }
1.187 + else {
1.188 + for (int j = 0; j < read; j++) {
1.189 + if (cbuf[j] == patterns[i][0]) {
1.190 + unread(cbuf, j, read - j);
1.191 + return j;
1.192 + }
1.193 + }
1.194 + }
1.195 + }
1.196 + if (!doUnfold) {
1.197 + return read;
1.198 + }
1.199 + else {
1.200 + unread(cbuf, off, read);
1.201 + }
1.202 +
1.203 + unfold();
1.204 +
1.205 + return super.read(cbuf, off, maxPatternLength);
1.206 + }
1.207 +
1.208 + private void unfold() throws IOException {
1.209 + // need to loop since one line fold might be directly followed by another
1.210 + boolean didUnfold;
1.211 + do {
1.212 + didUnfold = false;
1.213 +
1.214 + for (int i = 0; i < buffers.length; i++) {
1.215 + int read = 0;
1.216 + while (read < buffers[i].length) {
1.217 + final int partialRead = super.read(buffers[i], read, buffers[i].length - read);
1.218 + if (partialRead < 0) {
1.219 + break;
1.220 + }
1.221 + read += partialRead;
1.222 + }
1.223 + if (read > 0) {
1.224 + if (!Arrays.equals(patterns[i], buffers[i])) {
1.225 + unread(buffers[i], 0, read);
1.226 + }
1.227 + else {
1.228 + if (log.isTraceEnabled()) {
1.229 + log.trace("Unfolding...");
1.230 + }
1.231 + linesUnfolded++;
1.232 + didUnfold = true;
1.233 + }
1.234 + }
1.235 +// else {
1.236 +// return read;
1.237 +// }
1.238 + }
1.239 + }
1.240 + while (didUnfold);
1.241 + }
1.242 +}
