1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/net/fortuna/ical4j/data/FoldingWriter.java Tue Feb 10 18:12:00 2015 +0100
1.3 @@ -0,0 +1,155 @@
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.FilterWriter;
1.38 +import java.io.IOException;
1.39 +import java.io.Writer;
1.40 +
1.41 +import org.apache.commons.logging.Log;
1.42 +import org.apache.commons.logging.LogFactory;
1.43 +
1.44 +/**
1.45 + * <pre>
1.46 + * $Id$ [Apr 6, 2004]
1.47 + * </pre>
1.48 + *
1.49 + * A writer that performs iCalendar folding as it writes.
1.50 + * @author Ben Fortuna
1.51 + */
1.52 +public class FoldingWriter extends FilterWriter {
1.53 +
1.54 + /**
1.55 + * reduced to 73 to be consistent with Apple iCal..
1.56 + */
1.57 + public static final int REDUCED_FOLD_LENGTH = 73;
1.58 +
1.59 + /**
1.60 + * Lines of text SHOULD NOT be longer than 75 octets, excluding the line break.
1.61 + */
1.62 + public static final int MAX_FOLD_LENGTH = 75;
1.63 +
1.64 + private static final char[] FOLD_PATTERN = { '\r', '\n', ' ' };
1.65 +
1.66 + private final Log log = LogFactory.getLog(FoldingWriter.class);
1.67 +
1.68 + private int lineLength;
1.69 +
1.70 + private final int foldLength;
1.71 +
1.72 + /**
1.73 + * @param writer a writer to write output to
1.74 + * @param foldLength the maximum line length
1.75 + */
1.76 + public FoldingWriter(final Writer writer, final int foldLength) {
1.77 + super(writer);
1.78 + this.foldLength = Math.min(foldLength, MAX_FOLD_LENGTH);
1.79 + }
1.80 +
1.81 + /**
1.82 + * @param writer a writer to write output to
1.83 + */
1.84 + public FoldingWriter(final Writer writer) {
1.85 + this(writer, REDUCED_FOLD_LENGTH);
1.86 + }
1.87 +
1.88 + /**
1.89 + * {@inheritDoc}
1.90 + */
1.91 + public final void write(final int c) throws IOException {
1.92 +
1.93 + /*
1.94 + * super.write(c); if (c == '\n') { lineLength = 0; } else { lineLength += 1; } if (lineLength >= FOLD_LENGTH) {
1.95 + * super.write(FOLD_PATTERN); }
1.96 + */
1.97 + write(new char[] { (char) c }, 0, 1);
1.98 + }
1.99 +
1.100 + /**
1.101 + * {@inheritDoc}
1.102 + */
1.103 + public final void write(final char[] buffer, final int offset,
1.104 + final int length) throws IOException {
1.105 + final int maxIndex = offset + length - 1;
1.106 + for (int i = offset; i <= maxIndex; i++) {
1.107 +
1.108 + // debugging..
1.109 + if (log.isTraceEnabled()) {
1.110 + log.trace("char [" + buffer[i] + "], line length ["
1.111 + + lineLength + "]");
1.112 + }
1.113 +
1.114 + // check for fold first so we don't unnecessarily fold after
1.115 + // no more data..
1.116 + if (lineLength >= foldLength) {
1.117 + super.write(FOLD_PATTERN, 0, FOLD_PATTERN.length);
1.118 +
1.119 + // re-initialise to 1 to account for the space in fold pattern..
1.120 + lineLength = 1;
1.121 + }
1.122 +
1.123 + super.write(buffer[i]);
1.124 +
1.125 + if (buffer[i] == '\r' || buffer[i] == '\n') {
1.126 + lineLength = 0;
1.127 + }
1.128 + else {
1.129 + lineLength += 1;
1.130 + }
1.131 + }
1.132 + }
1.133 +
1.134 + /**
1.135 + * {@inheritDoc}
1.136 + */
1.137 + public final void write(final String str, final int off, final int len)
1.138 + throws IOException {
1.139 + write(str.toCharArray(), off, len);
1.140 + }
1.141 +
1.142 + /*
1.143 + * (non-Javadoc)
1.144 + * @see java.io.FilterWriter#write(java.lang.String, int, int) public void write(String arg0, int arg1, int arg2)
1.145 + * throws IOException { super.write(arg0, arg1, arg2); if (arg0.indexOf('\n') >= 0) { lineLength = 0; } else {
1.146 + * lineLength += 1; } fold(); }
1.147 + */
1.148 +
1.149 + /*
1.150 + * (non-Javadoc)
1.151 + * @see java.io.Writer#write(java.lang.String) public void write(String arg0) throws IOException {
1.152 + * /* if (lineLength +
1.153 + * arg0.length() >= FOLD_LENGTH) { super.write(arg0.substring(0,FOLD_LENGTH-lineLength-1));
1.154 + * super.write(FOLD_PATTERN); super.write(arg0.substring(FOLD_LENGTH-lineLength)); } else { super.write(arg0); } if
1.155 + * (arg0.indexOf('\n') >= 0) { lineLength = 0; } else { lineLength += 1; } fold(); char[] chars =
1.156 + * arg0.toCharArray(); for (int i=0; i <chars.length; i++) { write(chars[i]); } }
1.157 + */
1.158 +}
