com.ibm.icu.lang.CharacterProperties Maven / Gradle / Ivy
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// © 2018 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html#License
package com.ibm.icu.lang;
import com.ibm.icu.impl.CharacterPropertiesImpl;
import com.ibm.icu.text.UnicodeSet;
import com.ibm.icu.util.CodePointMap;
import com.ibm.icu.util.CodePointTrie;
import com.ibm.icu.util.MutableCodePointTrie;
/**
* Sets and maps for Unicode properties.
* The methods here return an object per property:
* A set for each ICU-supported binary property with all code points for which the property is true.
* A map for each ICU-supported enumerated/catalog/int-valued property
* which maps all Unicode code points to their values for that property.
*
* For details see the method descriptions.
* For lookup of property values by code point see class {@link UCharacter}.
*
* @stable ICU 63
*/
public final class CharacterProperties {
private CharacterProperties() {} // all-static
private static final UnicodeSet sets[] = new UnicodeSet[UProperty.BINARY_LIMIT];
private static final CodePointMap maps[] = new CodePointMap[UProperty.INT_LIMIT - UProperty.INT_START];
private static UnicodeSet makeSet(int property) {
UnicodeSet set = new UnicodeSet();
UnicodeSet inclusions = CharacterPropertiesImpl.getInclusionsForProperty(property);
int numRanges = inclusions.getRangeCount();
int startHasProperty = -1;
for (int i = 0; i < numRanges; ++i) {
int rangeEnd = inclusions.getRangeEnd(i);
for (int c = inclusions.getRangeStart(i); c <= rangeEnd; ++c) {
// TODO: Get a UCharacterProperty.BinaryProperty to avoid the property dispatch.
if (UCharacter.hasBinaryProperty(c, property)) {
if (startHasProperty < 0) {
// Transition from false to true.
startHasProperty = c;
}
} else if (startHasProperty >= 0) {
// Transition from true to false.
set.add(startHasProperty, c - 1);
startHasProperty = -1;
}
}
}
if (startHasProperty >= 0) {
set.add(startHasProperty, 0x10FFFF);
}
return set.freeze();
}
private static CodePointMap makeMap(int property) {
int nullValue = property == UProperty.SCRIPT ? UScript.UNKNOWN : 0;
MutableCodePointTrie mutableTrie = new MutableCodePointTrie(nullValue, nullValue);
UnicodeSet inclusions = CharacterPropertiesImpl.getInclusionsForProperty(property);
int numRanges = inclusions.getRangeCount();
int start = 0;
int value = nullValue;
for (int i = 0; i < numRanges; ++i) {
int rangeEnd = inclusions.getRangeEnd(i);
for (int c = inclusions.getRangeStart(i); c <= rangeEnd; ++c) {
// TODO: Get a UCharacterProperty.IntProperty to avoid the property dispatch.
int nextValue = UCharacter.getIntPropertyValue(c, property);
if (value != nextValue) {
if (value != nullValue) {
mutableTrie.setRange(start, c - 1, value);
}
start = c;
value = nextValue;
}
}
}
if (value != 0) {
mutableTrie.setRange(start, 0x10FFFF, value);
}
CodePointTrie.Type type;
if (property == UProperty.BIDI_CLASS || property == UProperty.GENERAL_CATEGORY) {
type = CodePointTrie.Type.FAST;
} else {
type = CodePointTrie.Type.SMALL;
}
CodePointTrie.ValueWidth valueWidth;
// TODO: UCharacterProperty.IntProperty
int max = UCharacter.getIntPropertyMaxValue(property);
if (max <= 0xff) {
valueWidth = CodePointTrie.ValueWidth.BITS_8;
} else if (max <= 0xffff) {
valueWidth = CodePointTrie.ValueWidth.BITS_16;
} else {
valueWidth = CodePointTrie.ValueWidth.BITS_32;
}
return mutableTrie.buildImmutable(type, valueWidth);
}
/**
* Returns a frozen UnicodeSet for a binary property.
* Throws an exception if the property number is not one for a binary property.
*
*
The returned set contains all code points for which the property is true.
*
* @param property {@link UProperty#BINARY_START}..{@link UProperty#BINARY_LIMIT}-1
* @return the property as a set
* @see UProperty
* @see UCharacter#hasBinaryProperty
* @stable ICU 63
*/
public static final UnicodeSet getBinaryPropertySet(int property) {
if (property < 0 || UProperty.BINARY_LIMIT <= property) {
throw new IllegalArgumentException("" + property +
" is not a constant for a UProperty binary property");
}
synchronized(sets) {
UnicodeSet set = sets[property];
if (set == null) {
sets[property] = set = makeSet(property);
}
return set;
}
}
/**
* Returns an immutable CodePointMap for an enumerated/catalog/int-valued property.
* Throws an exception if the property number is not one for an "int property".
*
*
The returned object maps all Unicode code points to their values for that property.
* For documentation of the integer values see {@link UCharacter#getIntPropertyValue(int, int)}.
*
*
The actual type of the returned object differs between properties
* and may change over time.
*
* @param property {@link UProperty#INT_START}..{@link UProperty#INT_LIMIT}-1
* @return the property as a map
* @see UProperty
* @see UCharacter#getIntPropertyValue
* @stable ICU 63
*/
public static final CodePointMap getIntPropertyMap(int property) {
if (property < UProperty.INT_START || UProperty.INT_LIMIT <= property) {
throw new IllegalArgumentException("" + property +
" is not a constant for a UProperty int property");
}
synchronized(maps) {
CodePointMap map = maps[property - UProperty.INT_START];
if (map == null) {
maps[property - UProperty.INT_START] = map = makeMap(property);
}
return map;
}
}
}