Caldavsync Sources: src/net/fortuna/ical4j/util/Strings.java@fb9019fb1bf7 (annotated)

src/net/fortuna/ical4j/util/Strings.java@fb9019fb1bf7 (annotated)

src/net/fortuna/ical4j/util/Strings.java

Tue, 10 Feb 2015 18:12:00 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Tue, 10 Feb 2015 18:12:00 +0100
changeset 0: fb9019fb1bf7
permissions: -rw-r--r--

Import initial revisions of existing project AndroidCaldavSyncAdapater,
forked from upstream repository at 27e8a0f8495c92e0780d450bdf0c7cec77a03a55.

 /**
  * Copyright (c) 2012, Ben Fortuna
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  *  o Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *
  *  o Redistributions in binary form must reproduce the above copyright
  * notice, this list of conditions and the following disclaimer in the
  * documentation and/or other materials provided with the distribution.
  *
  *  o Neither the name of Ben Fortuna nor the names of any other contributors
  * may be used to endorse or promote products derived from this software
  * without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 package net.fortuna.ical4j.util;
 import java.util.regex.Pattern;
 /**
  * $Id$ [23-Apr-2004]
  *
  * Utility methods for working with parameters.
  * @author Ben Fortuna
  * <pre>
  * 4.3.11 Text
  *
  *    Value Name: TEXT
  *
  *    Purpose This value type is used to identify values that contain human
  *    readable text.
  *
  *    Formal Definition: The character sets supported by this revision of
  *    iCalendar are UTF-8 and US ASCII thereof. The applicability to other
  *    character sets is for future work. The value type is defined by the
  *    following notation.
  *
  *      text       = *(TSAFE-CHAR / ":" / DQUOTE / ESCAPED-CHAR)
  *      ; Folded according to description above
  *
  *      ESCAPED-CHAR = "\\" / "\;" / "\," / "\N" / "\n")
  *         ; \\ encodes \, \N or \n encodes newline
  *         ; \; encodes ;, \, encodes ,
  *
  *      TSAFE-CHAR = %x20-21 / %x23-2B / %x2D-39 / %x3C-5B
  *                   %x5D-7E / NON-US-ASCII
  *         ; Any character except CTLs not needed by the current
  *         ; character set, DQUOTE, ";", ":", "\", ","
  *
  *      Note: Certain other character sets may require modification of the
  *      above definitions, but this is beyond the scope of this document.
  *
  *    Description: If the property permits, multiple "text" values are
  *    specified by a COMMA character (US-ASCII decimal 44) separated list
  *    of values.
  *
  *    The language in which the text is represented can be controlled by
  *    the "LANGUAGE" property parameter.
  *
  *    An intentional formatted text line break MUST only be included in a
  *    "TEXT" property value by representing the line break with the
  *    character sequence of BACKSLASH (US-ASCII decimal 92), followed by a
  *    LATIN SMALL LETTER N (US-ASCII decimal 110) or a LATIN CAPITAL LETTER
  *    N (US-ASCII decimal 78), that is "\n" or "\N".
  *
  *    The "TEXT" property values may also contain special characters that
  *    are used to signify delimiters, such as a COMMA character for lists
  *    of values or a SEMICOLON character for structured values. In order to
  *    support the inclusion of these special characters in "TEXT" property
  *    values, they MUST be escaped with a BACKSLASH character. A BACKSLASH
  *    character (US-ASCII decimal 92) in a "TEXT" property value MUST be
  *    escaped with another BACKSLASH character. A COMMA character in a
  *    "TEXT" property value MUST be escaped with a BACKSLASH character
  *    (US-ASCII decimal 92). A SEMICOLON character in a "TEXT" property
  *    value MUST be escaped with a BACKSLASH character (US-ASCII decimal
  *    92).  However, a COLON character in a "TEXT" property value SHALL NOT
  *    be escaped with a BACKSLASH character.Example: A multiple line value
  *    of:
  *
  *      Project XYZ Final Review
  *      Conference Room - 3B
  *      Come Prepared.
  *
  *    would be represented as:
  *
  *      Project XYZ Final Review\nConference Room - 3B\nCome Prepared.
  * </pre>
  */
 public final class Strings {
     /**
      * Defines a regular expression representing all parameter strings that
      * should be quoted.
      */
     public static final Pattern PARAM_QUOTE_PATTERN = Pattern.compile("[:;,]|[^\\p{ASCII}]");
     private static final Pattern ESCAPE_PUNCTUATION_PATTERN = Pattern.compile("([,;])");
     private static final Pattern UNESCAPE_PUNCTUATION_PATTERN = Pattern.compile("\\\\([,;\"])");
     private static final Pattern ESCAPE_NEWLINE_PATTERN = Pattern.compile("\r?\n");
     private static final Pattern UNESCAPE_NEWLINE_PATTERN = Pattern.compile("(?<!\\\\)\\\\n");
     private static final Pattern ESCAPE_BACKSLASH_PATTERN = Pattern.compile("\\\\");
     private static final Pattern UNESCAPE_BACKSLASH_PATTERN = Pattern.compile("\\\\\\\\");
     /**
      * A string used to denote the start (and end) of iCalendar content lines.
      */
     public static final String LINE_SEPARATOR = "\r\n";
     /**
      * Constructor made private to prevent instantiation.
      */
     private Strings() {
     }
     /**
      * Convenience method for adding quotes. The specified
      * object is converted to a string representation by
      * calling its <code>toString()</code> method.
      * @param aValue an object to quote
      * @return a quoted string
      */
     public static String quote(final Object aValue) {
         if (aValue != null) {
             return "\"" + aValue + "\"";
         }
         return "\"\"";
     }
     /**
      * Convenience method for removing surrounding quotes
      * from a string value.
      * @param aValue a string to remove quotes from
      * @return an un-quoted string
      */
     public static String unquote(final String aValue) {
         if (aValue != null && aValue.startsWith("\"") && aValue.endsWith("\"")) {
             return aValue.substring(0, aValue.length() - 1).substring(1);
         }
         return aValue;
     }
     /**
      * Convenience method for escaping special characters.
      * @param aValue a string value to escape
      * @return an escaped representation of the specified
      * string
      */
     public static String escape(final String aValue) {
         return escapePunctuation(escapeNewline(escapeBackslash(aValue)));
     }
     /**
      * Convenience method for replacing escaped special characters
      * with their original form.
      * @param aValue a string value to unescape
      * @return a string representation of the specified
      * string with escaped characters replaced with their
      * original form
      */
     public static String unescape(final String aValue) {
         return unescapeBackslash(unescapeNewline(unescapePunctuation(aValue)));
     }
     private static String escapePunctuation(String value) {
         if (value != null) {
             return ESCAPE_PUNCTUATION_PATTERN.matcher(value).replaceAll("\\\\$1");
         }
         return value;
     }
     private static String unescapePunctuation(String value) {
         if (value != null) {
             return UNESCAPE_PUNCTUATION_PATTERN.matcher(value).replaceAll("$1");
         }
         return value;
     }
     public static String escapeNewline(String value) {
         if (value != null) {
             return ESCAPE_NEWLINE_PATTERN.matcher(value).replaceAll("\\\\n");
         }
         return value;
     }
     private static String unescapeNewline(String value) {
         if (value != null) {
             return UNESCAPE_NEWLINE_PATTERN.matcher(value).replaceAll("\n");
         }
         return value;
     }
     private static String escapeBackslash(String value) {
         if (value != null) {
             return ESCAPE_BACKSLASH_PATTERN.matcher(value).replaceAll("\\\\\\\\");
         }
         return value;
     }
     private static String unescapeBackslash(String value) {
         if (value != null) {
             return UNESCAPE_BACKSLASH_PATTERN.matcher(value).replaceAll("\\\\");
         }
         return value;
     }
     /**
      * Wraps <code>java.lang.String.valueOf()</code> to return an empty string
      * where the specified object is null.
      * @param object an object instance
      * @return a string representation of the object
      */
     public static String valueOf(final Object object) {
         if (object == null) {
             return "";
         }
         return object.toString();
     }
 }

Caldavsync Sources / annotate

src/net/fortuna/ical4j/util/Strings.java@fb9019fb1bf7 (annotated)

src/net/fortuna/ical4j/util/Strings.java