/*
* Copyright (c) 2005, 2015, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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/*
*******************************************************************************
* Copyright (C) 1996-2015, International Business Machines Corporation and
* others. All Rights Reserved.
*******************************************************************************
*/
package sun.text.normalizer;
import java.io.IOException;
import java.text.ParsePosition;
import java.util.ArrayList;
import java.util.TreeSet;
/**
* A mutable set of Unicode characters and multicharacter strings.
* Objects of this class represent <em>character classes</em> used
* in regular expressions. A character specifies a subset of Unicode
* code points. Legal code points are U+0000 to U+10FFFF, inclusive.
*
* Note: method freeze() will not only make the set immutable, but
* also makes important methods much higher performance:
* contains(c), containsNone(...), span(...), spanBack(...) etc.
* After the object is frozen, any subsequent call that wants to change
* the object will throw UnsupportedOperationException.
*
* <p>The UnicodeSet class is not designed to be subclassed.
*
* <p><code>UnicodeSet</code> supports two APIs. The first is the
* <em>operand</em> API that allows the caller to modify the value of
* a <code>UnicodeSet</code> object. It conforms to Java 2's
* <code>java.util.Set</code> interface, although
* <code>UnicodeSet</code> does not actually implement that
* interface. All methods of <code>Set</code> are supported, with the
* modification that they take a character range or single character
* instead of an <code>Object</code>, and they take a
* <code>UnicodeSet</code> instead of a <code>Collection</code>. The
* operand API may be thought of in terms of boolean logic: a boolean
* OR is implemented by <code>add</code>, a boolean AND is implemented
* by <code>retain</code>, a boolean XOR is implemented by
* <code>complement</code> taking an argument, and a boolean NOT is
* implemented by <code>complement</code> with no argument. In terms
* of traditional set theory function names, <code>add</code> is a
* union, <code>retain</code> is an intersection, <code>remove</code>
* is an asymmetric difference, and <code>complement</code> with no
* argument is a set complement with respect to the superset range
* <code>MIN_VALUE-MAX_VALUE</code>
*
* <p>The second API is the
* <code>applyPattern()</code>/<code>toPattern()</code> API from the
* <code>java.text.Format</code>-derived classes. Unlike the
* methods that add characters, add categories, and control the logic
* of the set, the method <code>applyPattern()</code> sets all
* attributes of a <code>UnicodeSet</code> at once, based on a
* string pattern.
*
* <p><b>Pattern syntax</b></p>
*
* Patterns are accepted by the constructors and the
* <code>applyPattern()</code> methods and returned by the
* <code>toPattern()</code> method. These patterns follow a syntax
* similar to that employed by version 8 regular expression character
* classes. Here are some simple examples:
*
* <blockquote>
* <table>
* <tr align="top">
* <td nowrap valign="top" align="left"><code>[]</code></td>
* <td valign="top">No characters</td>
* </tr><tr align="top">
* <td nowrap valign="top" align="left"><code>[a]</code></td>
* <td valign="top">The character 'a'</td>
* </tr><tr align="top">
* <td nowrap valign="top" align="left"><code>[ae]</code></td>
* <td valign="top">The characters 'a' and 'e'</td>
* </tr>
* <tr>
* <td nowrap valign="top" align="left"><code>[a-e]</code></td>
* <td valign="top">The characters 'a' through 'e' inclusive, in Unicode code
* point order</td>
* </tr>
* <tr>
* <td nowrap valign="top" align="left"><code>[\\u4E01]</code></td>
* <td valign="top">The character U+4E01</td>
* </tr>
* <tr>
* <td nowrap valign="top" align="left"><code>[a{ab}{ac}]</code></td>
* <td valign="top">The character 'a' and the multicharacter strings "ab" and
* "ac"</td>
* </tr>
* <tr>
* <td nowrap valign="top" align="left"><code>[\p{Lu}]</code></td>
* <td valign="top">All characters in the general category Uppercase Letter</td>
* </tr>
* </table>
* </blockquote>
*
* Any character may be preceded by a backslash in order to remove any special
* meaning. White space characters, as defined by the Unicode Pattern_White_Space property, are
* ignored, unless they are escaped.
*
* <p>Property patterns specify a set of characters having a certain
* property as defined by the Unicode standard. Both the POSIX-like
* "[:Lu:]" and the Perl-like syntax "\p{Lu}" are recognized. For a
* complete list of supported property patterns, see the User's Guide
* for UnicodeSet at
* <a href="http://www.icu-project.org/userguide/unicodeSet.html">
* http://www.icu-project.org/userguide/unicodeSet.html</a>.
* Actual determination of property data is defined by the underlying
* Unicode database as implemented by UCharacter.
*
* <p>Patterns specify individual characters, ranges of characters, and
* Unicode property sets. When elements are concatenated, they
* specify their union. To complement a set, place a '^' immediately
* after the opening '['. Property patterns are inverted by modifying
* their delimiters; "[:^foo]" and "\P{foo}". In any other location,
* '^' has no special meaning.
*
* <p>Ranges are indicated by placing two a '-' between two
* characters, as in "a-z". This specifies the range of all
* characters from the left to the right, in Unicode order. If the
* left character is greater than or equal to the
* right character it is a syntax error. If a '-' occurs as the first
* character after the opening '[' or '[^', or if it occurs as the
* last character before the closing ']', then it is taken as a
* literal. Thus "[a\\-b]", "[-ab]", and "[ab-]" all indicate the same
* set of three characters, 'a', 'b', and '-'.
*
* <p>Sets may be intersected using the {@literal '&'} operator or the asymmetric
* set difference may be taken using the '-' operator, for example,
* "{@code [[:L:]&[\\u0000-\\u0FFF]]}" indicates the set of all Unicode letters
* with values less than 4096. Operators ({@literal '&'} and '|') have equal
* precedence and bind left-to-right. Thus
* "[[:L:]-[a-z]-[\\u0100-\\u01FF]]" is equivalent to
* "[[[:L:]-[a-z]]-[\\u0100-\\u01FF]]". This only really matters for
* difference; intersection is commutative.
*
* <table>
* <tr valign=top><td nowrap><code>[a]</code><td>The set containing 'a'
* <tr valign=top><td nowrap><code>[a-z]</code><td>The set containing 'a'
* through 'z' and all letters in between, in Unicode order
* <tr valign=top><td nowrap><code>[^a-z]</code><td>The set containing
* all characters but 'a' through 'z',
* that is, U+0000 through 'a'-1 and 'z'+1 through U+10FFFF
* <tr valign=top><td nowrap><code>[[<em>pat1</em>][<em>pat2</em>]]</code>
* <td>The union of sets specified by <em>pat1</em> and <em>pat2</em>
* <tr valign=top><td nowrap><code>[[<em>pat1</em>]&[<em>pat2</em>]]</code>
* <td>The intersection of sets specified by <em>pat1</em> and <em>pat2</em>
* <tr valign=top><td nowrap><code>[[<em>pat1</em>]-[<em>pat2</em>]]</code>
* <td>The asymmetric difference of sets specified by <em>pat1</em> and
* <em>pat2</em>
* <tr valign=top><td nowrap><code>[:Lu:] or \p{Lu}</code>
* <td>The set of characters having the specified
* Unicode property; in
* this case, Unicode uppercase letters
* <tr valign=top><td nowrap><code>[:^Lu:] or \P{Lu}</code>
* <td>The set of characters <em>not</em> having the given
* Unicode property
* </table>
*
* <p><b>Warning</b>: you cannot add an empty string ("") to a UnicodeSet.</p>
*
* <p><b>Formal syntax</b></p>
*
* <blockquote>
* <table>
* <tr align="top">
* <td nowrap valign="top" align="right"><code>pattern := </code></td>
* <td valign="top"><code>('[' '^'? item* ']') |
* property</code></td>
* </tr>
* <tr align="top">
* <td nowrap valign="top" align="right"><code>item := </code></td>
* <td valign="top"><code>char | (char '-' char) | pattern-expr<br>
* </code></td>
* </tr>
* <tr align="top">
* <td nowrap valign="top" align="right"><code>pattern-expr := </code></td>
* <td valign="top"><code>pattern | pattern-expr pattern |
* pattern-expr op pattern<br>
* </code></td>
* </tr>
* <tr align="top">
* <td nowrap valign="top" align="right"><code>op := </code></td>
* <td valign="top"><code>'&' | '-'<br>
* </code></td>
* </tr>
* <tr align="top">
* <td nowrap valign="top" align="right"><code>special := </code></td>
* <td valign="top"><code>'[' | ']' | '-'<br>
* </code></td>
* </tr>
* <tr align="top">
* <td nowrap valign="top" align="right"><code>char := </code></td>
* <td valign="top"><em>any character that is not</em><code> special<br>
* | ('\\' </code><em>any character</em><code>)<br>
* | ('\u' hex hex hex hex)<br>
* </code></td>
* </tr>
* <tr align="top">
* <td nowrap valign="top" align="right"><code>hex := </code></td>
* <td valign="top"><em>any character for which
* </em><code>Character.digit(c, 16)</code><em>
* returns a non-negative result</em></td>
* </tr>
* <tr>
* <td nowrap valign="top" align="right"><code>property := </code></td>
* <td valign="top"><em>a Unicode property set pattern</em></td>
* </tr>
* </table>
* <br>
* <table border="1">
* <tr>
* <td>Legend: <table>
* <tr>
* <td nowrap valign="top"><code>a := b</code></td>
* <td width="20" valign="top"> </td>
* <td valign="top"><code>a</code> may be replaced by <code>b</code> </td>
* </tr>
* <tr>
* <td nowrap valign="top"><code>a?</code></td>
* <td valign="top"></td>
* <td valign="top">zero or one instance of <code>a</code><br>
* </td>
* </tr>
* <tr>
* <td nowrap valign="top"><code>a*</code></td>
* <td valign="top"></td>
* <td valign="top">one or more instances of <code>a</code><br>
* </td>
* </tr>
* <tr>
* <td nowrap valign="top"><code>a | b</code></td>
* <td valign="top"></td>
* <td valign="top">either <code>a</code> or <code>b</code><br>
* </td>
* </tr>
* <tr>
* <td nowrap valign="top"><code>'a'</code></td>
* <td valign="top"></td>
* <td valign="top">the literal string between the quotes </td>
* </tr>
* </table>
* </td>
* </tr>
* </table>
* </blockquote>
* <p>To iterate over contents of UnicodeSet, the following are available:
* <ul><li>{@link #ranges()} to iterate through the ranges</li>
* <li>{@link #strings()} to iterate through the strings</li>
* <li>{@link #iterator()} to iterate through the entire contents in a single loop.
* That method is, however, not particularly efficient, since it "boxes" each code point into a String.
* </ul>
* All of the above can be used in <b>for</b> loops.
* The {@link com.ibm.icu.text.UnicodeSetIterator UnicodeSetIterator} can also be used, but not in <b>for</b> loops.
* <p>To replace, count elements, or delete spans, see {@link com.ibm.icu.text.UnicodeSetSpanner UnicodeSetSpanner}.
*
* @author Alan Liu
* @stable ICU 2.0
*/
class UnicodeSet {
private static final int LOW = 0x000000; // LOW <= all valid values. ZERO for codepoints
private static final int HIGH = 0x110000; // HIGH > all valid values. 10000 for code units.
// 110000 for codepoints
/**
* Minimum value that can be stored in a UnicodeSet.
* @stable ICU 2.0
*/
public static final int MIN_VALUE = LOW;
/**
* Maximum value that can be stored in a UnicodeSet.
* @stable ICU 2.0
*/
public static final int MAX_VALUE = HIGH - 1;
private int len; // length used; list may be longer to minimize reallocs
private int[] list; // MUST be terminated with HIGH
private int[] rangeList; // internal buffer
private int[] buffer; // internal buffer
// NOTE: normally the field should be of type SortedSet; but that is missing a public clone!!
// is not private so that UnicodeSetIterator can get access
TreeSet<String> strings = new TreeSet<String>();
/**
* The pattern representation of this set. This may not be the
* most economical pattern. It is the pattern supplied to
* applyPattern(), with variables substituted and whitespace
* removed. For sets constructed without applyPattern(), or
* modified using the non-pattern API, this string will be null,
* indicating that toPattern() must generate a pattern
* representation from the inversion list.
*/
private static final int START_EXTRA = 16; // initial storage. Must be >= 0
private static final int GROW_EXTRA = START_EXTRA; // extra amount for growth. Must be >= 0
private static UnicodeSet INCLUSION = null;
private volatile BMPSet bmpSet; // The set is frozen if bmpSet or stringSpan is not null.
private volatile UnicodeSetStringSpan stringSpan;
//----------------------------------------------------------------
// Public API
//----------------------------------------------------------------
/**
* Constructs an empty set.
* @stable ICU 2.0
*/
private UnicodeSet() {
list = new int[1 + START_EXTRA];
list[len++] = HIGH;
}
/**
* Constructs a copy of an existing set.
* @stable ICU 2.0
*/
private UnicodeSet(UnicodeSet other) {
set(other);
}
/**
* Constructs a set containing the given range. If <code>end >
* start</code> then an empty set is created.
*
* @param start first character, inclusive, of range
* @param end last character, inclusive, of range
* @stable ICU 2.0
*/
public UnicodeSet(int start, int end) {
this();
complement(start, end);
}
/**
* Constructs a set from the given pattern. See the class description
* for the syntax of the pattern language. Whitespace is ignored.
* @param pattern a string specifying what characters are in the set
* @exception java.lang.IllegalArgumentException if the pattern contains
* a syntax error.
* @stable ICU 2.0
*/
public UnicodeSet(String pattern) {
this();
applyPattern(pattern, null);
}
/**
* Make this object represent the same set as <code>other</code>.
* @param other a <code>UnicodeSet</code> whose value will be
* copied to this object
* @stable ICU 2.0
*/
public UnicodeSet set(UnicodeSet other) {
checkFrozen();
list = other.list.clone();
len = other.len;
strings = new TreeSet<String>(other.strings);
return this;
}
/**
* Returns the number of elements in this set (its cardinality)
* Note than the elements of a set may include both individual
* codepoints and strings.
*
* @return the number of elements in this set (its cardinality).
* @stable ICU 2.0
*/
public int size() {
int n = 0;
int count = getRangeCount();
for (int i = 0; i < count; ++i) {
n += getRangeEnd(i) - getRangeStart(i) + 1;
}
return n + strings.size();
}
// for internal use, after checkFrozen has been called
private UnicodeSet add_unchecked(int start, int end) {
if (start < MIN_VALUE || start > MAX_VALUE) {
throw new IllegalArgumentException("Invalid code point U+" + Utility.hex(start, 6));
}
if (end < MIN_VALUE || end > MAX_VALUE) {
throw new IllegalArgumentException("Invalid code point U+" + Utility.hex(end, 6));
}
if (start < end) {
add(range(start, end), 2, 0);
} else if (start == end) {
add(start);
}
return this;
}
/**
* Adds the specified character to this set if it is not already
* present. If this set already contains the specified character,
* the call leaves this set unchanged.
* @stable ICU 2.0
*/
public final UnicodeSet add(int c) {
checkFrozen();
return add_unchecked(c);
}
// for internal use only, after checkFrozen has been called
private final UnicodeSet add_unchecked(int c) {
if (c < MIN_VALUE || c > MAX_VALUE) {
throw new IllegalArgumentException("Invalid code point U+" + Utility.hex(c, 6));
}
// find smallest i such that c < list[i]
// if odd, then it is IN the set
// if even, then it is OUT of the set
int i = findCodePoint(c);
// already in set?
if ((i & 1) != 0) return this;
// HIGH is 0x110000
// assert(list[len-1] == HIGH);
// empty = [HIGH]
// [start_0, limit_0, start_1, limit_1, HIGH]
// [..., start_k-1, limit_k-1, start_k, limit_k, ..., HIGH]
// ^
// list[i]
// i == 0 means c is before the first range
if (c == list[i]-1) {
// c is before start of next range
list[i] = c;
// if we touched the HIGH mark, then add a new one
if (c == MAX_VALUE) {
ensureCapacity(len+1);
list[len++] = HIGH;
}
if (i > 0 && c == list[i-1]) {
// collapse adjacent ranges
// [..., start_k-1, c, c, limit_k, ..., HIGH]
// ^
// list[i]
System.arraycopy(list, i+1, list, i-1, len-i-1);
len -= 2;
}
}
else if (i > 0 && c == list[i-1]) {
// c is after end of prior range
list[i-1]++;
// no need to chcek for collapse here
}
else {
// At this point we know the new char is not adjacent to
// any existing ranges, and it is not 10FFFF.
// [..., start_k-1, limit_k-1, start_k, limit_k, ..., HIGH]
// ^
// list[i]
// [..., start_k-1, limit_k-1, c, c+1, start_k, limit_k, ..., HIGH]
// ^
// list[i]
// Don't use ensureCapacity() to save on copying.
// NOTE: This has no measurable impact on performance,
// but it might help in some usage patterns.
if (len+2 > list.length) {
int[] temp = new int[len + 2 + GROW_EXTRA];
if (i != 0) System.arraycopy(list, 0, temp, 0, i);
System.arraycopy(list, i, temp, i+2, len-i);
list = temp;
} else {
System.arraycopy(list, i, list, i+2, len-i);
}
list[i] = c;
list[i+1] = c+1;
len += 2;
}
return this;
}
/**
* Adds the specified multicharacter to this set if it is not already
* present. If this set already contains the multicharacter,
* the call leaves this set unchanged.
* Thus {@code "ch" => {"ch"}}
* <br><b>Warning: you cannot add an empty string ("") to a UnicodeSet.</b>
* @param s the source string
* @return this object, for chaining
* @stable ICU 2.0
*/
public final UnicodeSet add(CharSequence s) {
checkFrozen();
int cp = getSingleCP(s);
if (cp < 0) {
strings.add(s.toString());
} else {
add_unchecked(cp, cp);
}
return this;
}
/**
* Utility for getting code point from single code point CharSequence.
* See the public UTF16.getSingleCodePoint()
* @return a code point IF the string consists of a single one.
* otherwise returns -1.
* @param s to test
*/
private static int getSingleCP(CharSequence s) {
if (s.length() < 1) {
throw new IllegalArgumentException("Can't use zero-length strings in UnicodeSet");
}
if (s.length() > 2) return -1;
if (s.length() == 1) return s.charAt(0);
// at this point, len = 2
int cp = UTF16.charAt(s, 0);
if (cp > 0xFFFF) { // is surrogate pair
return cp;
}
return -1;
}
/**
* Complements the specified range in this set. Any character in
* the range will be removed if it is in this set, or will be
* added if it is not in this set. If {@code end > start}
* then an empty range is complemented, leaving the set unchanged.
*
* @param start first character, inclusive, of range to be removed
* from this set.
* @param end last character, inclusive, of range to be removed
* from this set.
* @stable ICU 2.0
*/
public UnicodeSet complement(int start, int end) {
checkFrozen();
if (start < MIN_VALUE || start > MAX_VALUE) {
throw new IllegalArgumentException("Invalid code point U+" + Utility.hex(start, 6));
}
if (end < MIN_VALUE || end > MAX_VALUE) {
throw new IllegalArgumentException("Invalid code point U+" + Utility.hex(end, 6));
}
if (start <= end) {
xor(range(start, end), 2, 0);
}
return this;
}
/**
* Returns true if this set contains the given character.
* @param c character to be checked for containment
* @return true if the test condition is met
* @stable ICU 2.0
*/
public boolean contains(int c) {
if (c < MIN_VALUE || c > MAX_VALUE) {
throw new IllegalArgumentException("Invalid code point U+" + Utility.hex(c, 6));
}
if (bmpSet != null) {
return bmpSet.contains(c);
}
if (stringSpan != null) {
return stringSpan.contains(c);
}
/*
// Set i to the index of the start item greater than ch
// We know we will terminate without length test!
int i = -1;
while (true) {
if (c < list[++i]) break;
}
*/
int i = findCodePoint(c);
return ((i & 1) != 0); // return true if odd
}
/**
* Returns the smallest value i such that c < list[i]. Caller
* must ensure that c is a legal value or this method will enter
* an infinite loop. This method performs a binary search.
* @param c a character in the range MIN_VALUE..MAX_VALUE
* inclusive
* @return the smallest integer i in the range 0..len-1,
* inclusive, such that c < list[i]
*/
private final int findCodePoint(int c) {
/* Examples:
findCodePoint(c)
set list[] c=0 1 3 4 7 8
=== ============== ===========
[] [110000] 0 0 0 0 0 0
[\u0000-\u0003] [0, 4, 110000] 1 1 1 2 2 2
[\u0004-\u0007] [4, 8, 110000] 0 0 0 1 1 2
[:all:] [0, 110000] 1 1 1 1 1 1
*/
// Return the smallest i such that c < list[i]. Assume
// list[len - 1] == HIGH and that c is legal (0..HIGH-1).
if (c < list[0]) return 0;
// High runner test. c is often after the last range, so an
// initial check for this condition pays off.
if (len >= 2 && c >= list[len-2]) return len-1;
int lo = 0;
int hi = len - 1;
// invariant: c >= list[lo]
// invariant: c < list[hi]
for (;;) {
int i = (lo + hi) >>> 1;
if (i == lo) return hi;
if (c < list[i]) {
hi = i;
} else {
lo = i;
}
}
}
/**
* Retains only the elements in this set that are contained in the
* specified set. In other words, removes from this set all of
* its elements that are not contained in the specified set. This
* operation effectively modifies this set so that its value is
* the <i>intersection</i> of the two sets.
*
* @param c set that defines which elements this set will retain.
* @stable ICU 2.0
*/
public UnicodeSet retainAll(UnicodeSet c) {
checkFrozen();
retain(c.list, c.len, 0);
strings.retainAll(c.strings);
return this;
}
/**
* Removes all of the elements from this set. This set will be
* empty after this call returns.
* @stable ICU 2.0
*/
public UnicodeSet clear() {
checkFrozen();
list[0] = HIGH;
len = 1;
strings.clear();
return this;
}
/**
* Iteration method that returns the number of ranges contained in
* this set.
* @see #getRangeStart
* @see #getRangeEnd
* @stable ICU 2.0
*/
public int getRangeCount() {
return len/2;
}
/**
* Iteration method that returns the first character in the
* specified range of this set.
* @exception ArrayIndexOutOfBoundsException if index is outside
* the range <code>0..getRangeCount()-1</code>
* @see #getRangeCount
* @see #getRangeEnd
* @stable ICU 2.0
*/
public int getRangeStart(int index) {
return list[index*2];
}
/**
* Iteration method that returns the last character in the
* specified range of this set.
* @exception ArrayIndexOutOfBoundsException if index is outside
* the range <code>0..getRangeCount()-1</code>
* @see #getRangeStart
* @see #getRangeEnd
* @stable ICU 2.0
*/
public int getRangeEnd(int index) {
return (list[index*2 + 1] - 1);
}
//----------------------------------------------------------------
// Implementation: Pattern parsing
//----------------------------------------------------------------
/**
* Parses the given pattern, starting at the given position. The character
* at pattern.charAt(pos.getIndex()) must be '[', or the parse fails.
* Parsing continues until the corresponding closing ']'. If a syntax error
* is encountered between the opening and closing brace, the parse fails.
* Upon return from a successful parse, the ParsePosition is updated to
* point to the character following the closing ']', and an inversion
* list for the parsed pattern is returned. This method
* calls itself recursively to parse embedded subpatterns.
*
* @param pattern the string containing the pattern to be parsed. The
* portion of the string from pos.getIndex(), which must be a '[', to the
* corresponding closing ']', is parsed.
* @param pos upon entry, the position at which to being parsing. The
* character at pattern.charAt(pos.getIndex()) must be a '['. Upon return
* from a successful parse, pos.getIndex() is either the character after the
* closing ']' of the parsed pattern, or pattern.length() if the closing ']'
* is the last character of the pattern string.
* @return an inversion list for the parsed substring
* of <code>pattern</code>
* @exception java.lang.IllegalArgumentException if the parse fails.
*/
private UnicodeSet applyPattern(String pattern,
ParsePosition pos) {
if ("[:age=3.2:]".equals(pattern)) {
checkFrozen();
VersionInfo version = VersionInfo.getInstance("3.2");
applyFilter(new VersionFilter(version), UCharacterProperty.SRC_PROPSVEC);
} else {
throw new IllegalStateException("UnicodeSet.applyPattern(unexpected pattern "
+ pattern + ")");
}
return this;
}
//----------------------------------------------------------------
// Implementation: Utility methods
//----------------------------------------------------------------
private void ensureCapacity(int newLen) {
if (newLen <= list.length) return;
int[] temp = new int[newLen + GROW_EXTRA];
System.arraycopy(list, 0, temp, 0, len);
list = temp;
}
private void ensureBufferCapacity(int newLen) {
if (buffer != null && newLen <= buffer.length) return;
buffer = new int[newLen + GROW_EXTRA];
}
/**
* Assumes start <= end.
*/
private int[] range(int start, int end) {
if (rangeList == null) {
rangeList = new int[] { start, end+1, HIGH };
} else {
rangeList[0] = start;
rangeList[1] = end+1;
}
return rangeList;
}
//----------------------------------------------------------------
// Implementation: Fundamental operations
//----------------------------------------------------------------
// polarity = 0, 3 is normal: x xor y
// polarity = 1, 2: x xor ~y == x === y
private UnicodeSet xor(int[] other, int otherLen, int polarity) {
ensureBufferCapacity(len + otherLen);
int i = 0, j = 0, k = 0;
int a = list[i++];
int b;
if (polarity == 1 || polarity == 2) {
b = LOW;
if (other[j] == LOW) { // skip base if already LOW
++j;
b = other[j];
}
} else {
b = other[j++];
}
// simplest of all the routines
// sort the values, discarding identicals!
while (true) {
if (a < b) {
buffer[k++] = a;
a = list[i++];
} else if (b < a) {
buffer[k++] = b;
b = other[j++];
} else if (a != HIGH) { // at this point, a == b
// discard both values!
a = list[i++];
b = other[j++];
} else { // DONE!
buffer[k++] = HIGH;
len = k;
break;
}
}
// swap list and buffer
int[] temp = list;
list = buffer;
buffer = temp;
return this;
}
// polarity = 0 is normal: x union y
// polarity = 2: x union ~y
// polarity = 1: ~x union y
// polarity = 3: ~x union ~y
private UnicodeSet add(int[] other, int otherLen, int polarity) {
ensureBufferCapacity(len + otherLen);
int i = 0, j = 0, k = 0;
int a = list[i++];
int b = other[j++];
// change from xor is that we have to check overlapping pairs
// polarity bit 1 means a is second, bit 2 means b is.
main:
while (true) {
switch (polarity) {
case 0: // both first; take lower if unequal
if (a < b) { // take a
// Back up over overlapping ranges in buffer[]
if (k > 0 && a <= buffer[k-1]) {
// Pick latter end value in buffer[] vs. list[]
a = max(list[i], buffer[--k]);
} else {
// No overlap
buffer[k++] = a;
a = list[i];
}
i++; // Common if/else code factored out
polarity ^= 1;
} else if (b < a) { // take b
if (k > 0 && b <= buffer[k-1]) {
b = max(other[j], buffer[--k]);
} else {
buffer[k++] = b;
b = other[j];
}
j++;
polarity ^= 2;
} else { // a == b, take a, drop b
if (a == HIGH) break main;
// This is symmetrical; it doesn't matter if
// we backtrack with a or b. - liu
if (k > 0 && a <= buffer[k-1]) {
a = max(list[i], buffer[--k]);
} else {
// No overlap
buffer[k++] = a;
a = list[i];
}
i++;
polarity ^= 1;
b = other[j++]; polarity ^= 2;
}
break;
case 3: // both second; take higher if unequal, and drop other
if (b <= a) { // take a
if (a == HIGH) break main;
buffer[k++] = a;
} else { // take b
if (b == HIGH) break main;
buffer[k++] = b;
}
a = list[i++]; polarity ^= 1; // factored common code
b = other[j++]; polarity ^= 2;
break;
case 1: // a second, b first; if b < a, overlap
if (a < b) { // no overlap, take a
buffer[k++] = a; a = list[i++]; polarity ^= 1;
} else if (b < a) { // OVERLAP, drop b
b = other[j++]; polarity ^= 2;
} else { // a == b, drop both!
if (a == HIGH) break main;
a = list[i++]; polarity ^= 1;
b = other[j++]; polarity ^= 2;
}
break;
case 2: // a first, b second; if a < b, overlap
if (b < a) { // no overlap, take b
buffer[k++] = b; b = other[j++]; polarity ^= 2;
} else if (a < b) { // OVERLAP, drop a
a = list[i++]; polarity ^= 1;
} else { // a == b, drop both!
if (a == HIGH) break main;
a = list[i++]; polarity ^= 1;
b = other[j++]; polarity ^= 2;
}
break;
}
}
buffer[k++] = HIGH; // terminate
len = k;
// swap list and buffer
int[] temp = list;
list = buffer;
buffer = temp;
return this;
}
// polarity = 0 is normal: x intersect y
// polarity = 2: x intersect ~y == set-minus
// polarity = 1: ~x intersect y
// polarity = 3: ~x intersect ~y
private UnicodeSet retain(int[] other, int otherLen, int polarity) {
ensureBufferCapacity(len + otherLen);
int i = 0, j = 0, k = 0;
int a = list[i++];
int b = other[j++];
// change from xor is that we have to check overlapping pairs
// polarity bit 1 means a is second, bit 2 means b is.
main:
while (true) {
switch (polarity) {
case 0: // both first; drop the smaller
if (a < b) { // drop a
a = list[i++]; polarity ^= 1;
} else if (b < a) { // drop b
b = other[j++]; polarity ^= 2;
} else { // a == b, take one, drop other
if (a == HIGH) break main;
buffer[k++] = a; a = list[i++]; polarity ^= 1;
b = other[j++]; polarity ^= 2;
}
break;
case 3: // both second; take lower if unequal
if (a < b) { // take a
buffer[k++] = a; a = list[i++]; polarity ^= 1;
} else if (b < a) { // take b
buffer[k++] = b; b = other[j++]; polarity ^= 2;
} else { // a == b, take one, drop other
if (a == HIGH) break main;
buffer[k++] = a; a = list[i++]; polarity ^= 1;
b = other[j++]; polarity ^= 2;
}
break;
case 1: // a second, b first;
if (a < b) { // NO OVERLAP, drop a
a = list[i++]; polarity ^= 1;
} else if (b < a) { // OVERLAP, take b
buffer[k++] = b; b = other[j++]; polarity ^= 2;
} else { // a == b, drop both!
if (a == HIGH) break main;
a = list[i++]; polarity ^= 1;
b = other[j++]; polarity ^= 2;
}
break;
case 2: // a first, b second; if a < b, overlap
if (b < a) { // no overlap, drop b
b = other[j++]; polarity ^= 2;
} else if (a < b) { // OVERLAP, take a
buffer[k++] = a; a = list[i++]; polarity ^= 1;
} else { // a == b, drop both!
if (a == HIGH) break main;
a = list[i++]; polarity ^= 1;
b = other[j++]; polarity ^= 2;
}
break;
}
}
buffer[k++] = HIGH; // terminate
len = k;
// swap list and buffer
int[] temp = list;
list = buffer;
buffer = temp;
return this;
}
private static final int max(int a, int b) {
return (a > b) ? a : b;
}
//----------------------------------------------------------------
// Generic filter-based scanning code
//----------------------------------------------------------------
private static interface Filter {
boolean contains(int codePoint);
}
private static final VersionInfo NO_VERSION = VersionInfo.getInstance(0, 0, 0, 0);
private static class VersionFilter implements Filter {
VersionInfo version;
VersionFilter(VersionInfo version) { this.version = version; }
public boolean contains(int ch) {
VersionInfo v = UCharacter.getAge(ch);
// Reference comparison ok; VersionInfo caches and reuses
// unique objects.
return v != NO_VERSION &&
v.compareTo(version) <= 0;
}
}
private static synchronized UnicodeSet getInclusions(int src) {
if (src != UCharacterProperty.SRC_PROPSVEC) {
throw new IllegalStateException("UnicodeSet.getInclusions(unknown src "+src+")");
}
if (INCLUSION == null) {
UnicodeSet incl = new UnicodeSet();
UCharacterProperty.INSTANCE.upropsvec_addPropertyStarts(incl);
INCLUSION = incl;
}
return INCLUSION;
}
/**
* Generic filter-based scanning code for UCD property UnicodeSets.
*/
private UnicodeSet applyFilter(Filter filter, int src) {
// Logically, walk through all Unicode characters, noting the start
// and end of each range for which filter.contain(c) is
// true. Add each range to a set.
//
// To improve performance, use an inclusions set which
// encodes information about character ranges that are known
// to have identical properties.
// getInclusions(src) contains exactly the first characters of
// same-value ranges for the given properties "source".
clear();
int startHasProperty = -1;
UnicodeSet inclusions = getInclusions(src);
int limitRange = inclusions.getRangeCount();
for (int j=0; j<limitRange; ++j) {
// get current range
int start = inclusions.getRangeStart(j);
int end = inclusions.getRangeEnd(j);
// for all the code points in the range, process
for (int ch = start; ch <= end; ++ch) {
// only add to the unicodeset on inflection points --
// where the hasProperty value changes to false
if (filter.contains(ch)) {
if (startHasProperty < 0) {
startHasProperty = ch;
}
} else if (startHasProperty >= 0) {
add_unchecked(startHasProperty, ch-1);
startHasProperty = -1;
}
}
}
if (startHasProperty >= 0) {
add_unchecked(startHasProperty, 0x10FFFF);
}
return this;
}
/**
* Is this frozen, according to the Freezable interface?
*
* @return value
* @stable ICU 3.8
*/
public boolean isFrozen() {
return (bmpSet != null || stringSpan != null);
}
/**
* Freeze this class, according to the Freezable interface.
*
* @return this
* @stable ICU 4.4
*/
public UnicodeSet freeze() {
if (!isFrozen()) {
// Do most of what compact() does before freezing because
// compact() will not work when the set is frozen.
// Small modification: Don't shrink if the savings would be tiny (<=GROW_EXTRA).
// Delete buffer first to defragment memory less.
buffer = null;
if (list.length > (len + GROW_EXTRA)) {
// Make the capacity equal to len or 1.
// We don't want to realloc of 0 size.
int capacity = (len == 0) ? 1 : len;
int[] oldList = list;
list = new int[capacity];
for (int i = capacity; i-- > 0;) {
list[i] = oldList[i];
}
}
// Optimize contains() and span() and similar functions.
if (!strings.isEmpty()) {
stringSpan = new UnicodeSetStringSpan(this, new ArrayList<String>(strings), UnicodeSetStringSpan.ALL);
}
if (stringSpan == null || !stringSpan.needsStringSpanUTF16()) {
// Optimize for code point spans.
// There are no strings, or
// all strings are irrelevant for span() etc. because
// all of each string's code points are contained in this set.
// However, fully contained strings are relevant for spanAndCount(),
// so we create both objects.
bmpSet = new BMPSet(list, len);
}
}
return this;
}
/**
* Span a string using this UnicodeSet.
* <p>To replace, count elements, or delete spans, see {@link com.ibm.icu.text.UnicodeSetSpanner UnicodeSetSpanner}.
* @param s The string to be spanned
* @param spanCondition The span condition
* @return the length of the span
* @stable ICU 4.4
*/
public int span(CharSequence s, SpanCondition spanCondition) {
return span(s, 0, spanCondition);
}
/**
* Span a string using this UnicodeSet.
* If the start index is less than 0, span will start from 0.
* If the start index is greater than the string length, span returns the string length.
* <p>To replace, count elements, or delete spans, see {@link com.ibm.icu.text.UnicodeSetSpanner UnicodeSetSpanner}.
* @param s The string to be spanned
* @param start The start index that the span begins
* @param spanCondition The span condition
* @return the string index which ends the span (i.e. exclusive)
* @stable ICU 4.4
*/
public int span(CharSequence s, int start, SpanCondition spanCondition) {
int end = s.length();
if (start < 0) {
start = 0;
} else if (start >= end) {
return end;
}
if (bmpSet != null) {
// Frozen set without strings, or no string is relevant for span().
return bmpSet.span(s, start, spanCondition, null);
}
if (stringSpan != null) {
return stringSpan.span(s, start, spanCondition);
} else if (!strings.isEmpty()) {
int which = spanCondition == SpanCondition.NOT_CONTAINED ? UnicodeSetStringSpan.FWD_UTF16_NOT_CONTAINED
: UnicodeSetStringSpan.FWD_UTF16_CONTAINED;
UnicodeSetStringSpan strSpan = new UnicodeSetStringSpan(this, new ArrayList<String>(strings), which);
if (strSpan.needsStringSpanUTF16()) {
return strSpan.span(s, start, spanCondition);
}
}
return spanCodePointsAndCount(s, start, spanCondition, null);
}
/**
* Same as span() but also counts the smallest number of set elements on any path across the span.
* <p>To replace, count elements, or delete spans, see {@link com.ibm.icu.text.UnicodeSetSpanner UnicodeSetSpanner}.
* @param outCount An output-only object (must not be null) for returning the count.
* @return the limit (exclusive end) of the span
*/
public int spanAndCount(CharSequence s, int start, SpanCondition spanCondition, OutputInt outCount) {
if (outCount == null) {
throw new IllegalArgumentException("outCount must not be null");
}
int end = s.length();
if (start < 0) {
start = 0;
} else if (start >= end) {
return end;
}
if (stringSpan != null) {
// We might also have bmpSet != null,
// but fully-contained strings are relevant for counting elements.
return stringSpan.spanAndCount(s, start, spanCondition, outCount);
} else if (bmpSet != null) {
return bmpSet.span(s, start, spanCondition, outCount);
} else if (!strings.isEmpty()) {
int which = spanCondition == SpanCondition.NOT_CONTAINED ? UnicodeSetStringSpan.FWD_UTF16_NOT_CONTAINED
: UnicodeSetStringSpan.FWD_UTF16_CONTAINED;
which |= UnicodeSetStringSpan.WITH_COUNT;
UnicodeSetStringSpan strSpan = new UnicodeSetStringSpan(this, new ArrayList<String>(strings), which);
return strSpan.spanAndCount(s, start, spanCondition, outCount);
}
return spanCodePointsAndCount(s, start, spanCondition, outCount);
}
private int spanCodePointsAndCount(CharSequence s, int start,
SpanCondition spanCondition, OutputInt outCount) {
// Pin to 0/1 values.
boolean spanContained = (spanCondition != SpanCondition.NOT_CONTAINED);
int c;
int next = start;
int length = s.length();
int count = 0;
do {
c = Character.codePointAt(s, next);
if (spanContained != contains(c)) {
break;
}
++count;
next += Character.charCount(c);
} while (next < length);
if (outCount != null) { outCount.value = count; }
return next;
}
/**
* Span a string backwards (from the fromIndex) using this UnicodeSet.
* If the fromIndex is less than 0, spanBack will return 0.
* If fromIndex is greater than the string length, spanBack will start from the string length.
* <p>To replace, count elements, or delete spans, see {@link com.ibm.icu.text.UnicodeSetSpanner UnicodeSetSpanner}.
* @param s The string to be spanned
* @param fromIndex The index of the char (exclusive) that the string should be spanned backwards
* @param spanCondition The span condition
* @return The string index which starts the span (i.e. inclusive).
* @stable ICU 4.4
*/
public int spanBack(CharSequence s, int fromIndex, SpanCondition spanCondition) {
if (fromIndex <= 0) {
return 0;
}
if (fromIndex > s.length()) {
fromIndex = s.length();
}
if (bmpSet != null) {
// Frozen set without strings, or no string is relevant for spanBack().
return bmpSet.spanBack(s, fromIndex, spanCondition);
}
if (stringSpan != null) {
return stringSpan.spanBack(s, fromIndex, spanCondition);
} else if (!strings.isEmpty()) {
int which = (spanCondition == SpanCondition.NOT_CONTAINED)
? UnicodeSetStringSpan.BACK_UTF16_NOT_CONTAINED
: UnicodeSetStringSpan.BACK_UTF16_CONTAINED;
UnicodeSetStringSpan strSpan = new UnicodeSetStringSpan(this, new ArrayList<String>(strings), which);
if (strSpan.needsStringSpanUTF16()) {
return strSpan.spanBack(s, fromIndex, spanCondition);
}
}
// Pin to 0/1 values.
boolean spanContained = (spanCondition != SpanCondition.NOT_CONTAINED);
int c;
int prev = fromIndex;
do {
c = Character.codePointBefore(s, prev);
if (spanContained != contains(c)) {
break;
}
prev -= Character.charCount(c);
} while (prev > 0);
return prev;
}
/**
* Clone a thawed version of this class, according to the Freezable interface.
* @return the clone, not frozen
* @stable ICU 4.4
*/
public UnicodeSet cloneAsThawed() {
UnicodeSet result = new UnicodeSet(this);
assert !result.isFrozen();
return result;
}
// internal function
private void checkFrozen() {
if (isFrozen()) {
throw new UnsupportedOperationException("Attempt to modify frozen object");
}
}
/**
* Argument values for whether span() and similar functions continue while the current character is contained vs.
* not contained in the set.
* <p>
* The functionality is straightforward for sets with only single code points, without strings (which is the common
* case):
* <ul>
* <li>CONTAINED and SIMPLE work the same.
* <li>CONTAINED and SIMPLE are inverses of NOT_CONTAINED.
* <li>span() and spanBack() partition any string the
* same way when alternating between span(NOT_CONTAINED) and span(either "contained" condition).
* <li>Using a
* complemented (inverted) set and the opposite span conditions yields the same results.
* </ul>
* When a set contains multi-code point strings, then these statements may not be true, depending on the strings in
* the set (for example, whether they overlap with each other) and the string that is processed. For a set with
* strings:
* <ul>
* <li>The complement of the set contains the opposite set of code points, but the same set of strings.
* Therefore, complementing both the set and the span conditions may yield different results.
* <li>When starting spans
* at different positions in a string (span(s, ...) vs. span(s+1, ...)) the ends of the spans may be different
* because a set string may start before the later position.
* <li>span(SIMPLE) may be shorter than
* span(CONTAINED) because it will not recursively try all possible paths. For example, with a set which
* contains the three strings "xy", "xya" and "ax", span("xyax", CONTAINED) will return 4 but span("xyax",
* SIMPLE) will return 3. span(SIMPLE) will never be longer than span(CONTAINED).
* <li>With either "contained" condition, span() and spanBack() may partition a string in different ways. For example,
* with a set which contains the two strings "ab" and "ba", and when processing the string "aba", span() will yield
* contained/not-contained boundaries of { 0, 2, 3 } while spanBack() will yield boundaries of { 0, 1, 3 }.
* </ul>
* Note: If it is important to get the same boundaries whether iterating forward or backward through a string, then
* either only span() should be used and the boundaries cached for backward operation, or an ICU BreakIterator could
* be used.
* <p>
* Note: Unpaired surrogates are treated like surrogate code points. Similarly, set strings match only on code point
* boundaries, never in the middle of a surrogate pair.
*
* @stable ICU 4.4
*/
public enum SpanCondition {
/**
* Continues a span() while there is no set element at the current position.
* Increments by one code point at a time.
* Stops before the first set element (character or string).
* (For code points only, this is like while contains(current)==false).
* <p>
* When span() returns, the substring between where it started and the position it returned consists only of
* characters that are not in the set, and none of its strings overlap with the span.
*
* @stable ICU 4.4
*/
NOT_CONTAINED,
/**
* Spans the longest substring that is a concatenation of set elements (characters or strings).
* (For characters only, this is like while contains(current)==true).
* <p>
* When span() returns, the substring between where it started and the position it returned consists only of set
* elements (characters or strings) that are in the set.
* <p>
* If a set contains strings, then the span will be the longest substring for which there
* exists at least one non-overlapping concatenation of set elements (characters or strings).
* This is equivalent to a POSIX regular expression for <code>(OR of each set element)*</code>.
* (Java/ICU/Perl regex stops at the first match of an OR.)
*
* @stable ICU 4.4
*/
CONTAINED,
/**
* Continues a span() while there is a set element at the current position.
* Increments by the longest matching element at each position.
* (For characters only, this is like while contains(current)==true).
* <p>
* When span() returns, the substring between where it started and the position it returned consists only of set
* elements (characters or strings) that are in the set.
* <p>
* If a set only contains single characters, then this is the same as CONTAINED.
* <p>
* If a set contains strings, then the span will be the longest substring with a match at each position with the
* longest single set element (character or string).
* <p>
* Use this span condition together with other longest-match algorithms, such as ICU converters
* (ucnv_getUnicodeSet()).
*
* @stable ICU 4.4
*/
SIMPLE,
}
}