-
Trie2
-
createFromSerialized(ByteBuffer): Trie2
-
get(int): int
-
getFromU16SingleLead(char): int
-
Range
-
iterator(): Iterator<Range>
-
defaultValueMapper: ValueMapper
-
iterator(ValueMapper): Iterator<Range>
-
ValueMapper
-
UTrie2Header
-
header: UTrie2Header
-
index: char[]
-
data16: int
-
data32: int[]
-
indexLength: int
-
dataLength: int
-
index2NullOffset: int
-
initialValue: int
-
errorValue: int
-
highStart: int
-
highValueIndex: int
-
dataNullOffset: int
-
UTRIE2_OPTIONS_VALUE_BITS_MASK: int
-
UTRIE2_SHIFT_1: int
-
UTRIE2_SHIFT_2: int
-
UTRIE2_SHIFT_1_2: int
-
UTRIE2_OMITTED_BMP_INDEX_1_LENGTH: int
-
UTRIE2_INDEX_2_BLOCK_LENGTH: int
-
UTRIE2_INDEX_2_MASK: int
-
UTRIE2_DATA_BLOCK_LENGTH: int
-
UTRIE2_DATA_MASK: int
-
UTRIE2_INDEX_SHIFT: int
-
UTRIE2_DATA_GRANULARITY: int
-
UTRIE2_LSCP_INDEX_2_OFFSET: int
-
UTRIE2_LSCP_INDEX_2_LENGTH: int
-
UTRIE2_INDEX_2_BMP_LENGTH: int
-
UTRIE2_UTF8_2B_INDEX_2_OFFSET: int
-
UTRIE2_UTF8_2B_INDEX_2_LENGTH: int
-
UTRIE2_INDEX_1_OFFSET: int
-
UTRIE2_BAD_UTF8_DATA_OFFSET: int
-
Trie2Iterator
-
rangeEnd(int, int, int): int
-
initHash(): int
-
hashByte(int, int): int
-
hashUChar32(int, int): int
-
hashInt(int, int): int
-
/*
* Copyright (c) 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
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*
*******************************************************************************
* Copyright (C) 2009-2014, International Business Machines Corporation and
* others. All Rights Reserved.
*******************************************************************************
*/
package sun.text.normalizer;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.util.Iterator;
import java.util.NoSuchElementException;
This is the interface and common implementation of a Unicode Trie2.
It is a kind of compressed table that maps from Unicode code points (0..0x10ffff)
to 16- or 32-bit integer values. It works best when there are ranges of
characters with the same value, which is generally the case with Unicode
character properties.
This is the second common version of a Unicode trie (hence the name Trie2).
/**
* This is the interface and common implementation of a Unicode Trie2.
* It is a kind of compressed table that maps from Unicode code points (0..0x10ffff)
* to 16- or 32-bit integer values. It works best when there are ranges of
* characters with the same value, which is generally the case with Unicode
* character properties.
*
* This is the second common version of a Unicode trie (hence the name Trie2).
*
*/
abstract class Trie2 implements Iterable<Trie2.Range> {
Create a Trie2 from its serialized form. Inverse of utrie2_serialize().
Reads from the current position and leaves the buffer after the end of the trie.
The serialized format is identical between ICU4C and ICU4J, so this function
will work with serialized Trie2s from either.
The actual type of the returned Trie2 will be either Trie2_16 or Trie2_32, depending
on the width of the data.
To obtain the width of the Trie2, check the actual class type of the returned Trie2.
Or use the createFromSerialized() function of Trie2_16 or Trie2_32, which will
return only Tries of their specific type/size.
The serialized Trie2 on the stream may be in either little or big endian byte order.
This allows using serialized Tries from ICU4C without needing to consider the
byte order of the system that created them.
Params: - bytes – a byte buffer to the serialized form of a UTrie2.
Throws: - IllegalArgumentException – if the stream does not contain a serialized Trie2.
- IOException – if a read error occurs in the buffer.
Returns: An unserialized Trie2, ready for use.
/**
* Create a Trie2 from its serialized form. Inverse of utrie2_serialize().
*
* Reads from the current position and leaves the buffer after the end of the trie.
*
* The serialized format is identical between ICU4C and ICU4J, so this function
* will work with serialized Trie2s from either.
*
* The actual type of the returned Trie2 will be either Trie2_16 or Trie2_32, depending
* on the width of the data.
*
* To obtain the width of the Trie2, check the actual class type of the returned Trie2.
* Or use the createFromSerialized() function of Trie2_16 or Trie2_32, which will
* return only Tries of their specific type/size.
*
* The serialized Trie2 on the stream may be in either little or big endian byte order.
* This allows using serialized Tries from ICU4C without needing to consider the
* byte order of the system that created them.
*
* @param bytes a byte buffer to the serialized form of a UTrie2.
* @return An unserialized Trie2, ready for use.
* @throws IllegalArgumentException if the stream does not contain a serialized Trie2.
* @throws IOException if a read error occurs in the buffer.
*
*/
public static Trie2 createFromSerialized(ByteBuffer bytes) throws IOException {
// From ICU4C utrie2_impl.h
// * Trie2 data structure in serialized form:
// *
// * UTrie2Header header;
// * uint16_t index[header.index2Length];
// * uint16_t data[header.shiftedDataLength<<2]; -- or uint32_t data[...]
// * @internal
// */
// typedef struct UTrie2Header {
// /** "Tri2" in big-endian US-ASCII (0x54726932) */
// uint32_t signature;
// /**
// * options bit field:
// * 15.. 4 reserved (0)
// * 3.. 0 UTrie2ValueBits valueBits
// */
// uint16_t options;
//
// /** UTRIE2_INDEX_1_OFFSET..UTRIE2_MAX_INDEX_LENGTH */
// uint16_t indexLength;
//
// /** (UTRIE2_DATA_START_OFFSET..UTRIE2_MAX_DATA_LENGTH)>>UTRIE2_INDEX_SHIFT */
// uint16_t shiftedDataLength;
//
// /** Null index and data blocks, not shifted. */
// uint16_t index2NullOffset, dataNullOffset;
//
// /**
// * First code point of the single-value range ending with U+10ffff,
// * rounded up and then shifted right by UTRIE2_SHIFT_1.
// */
// uint16_t shiftedHighStart;
// } UTrie2Header;
ByteOrder outerByteOrder = bytes.order();
try {
UTrie2Header header = new UTrie2Header();
/* check the signature */
header.signature = bytes.getInt();
switch (header.signature) {
case 0x54726932:
// The buffer is already set to the trie data byte order.
break;
case 0x32697254:
// Temporarily reverse the byte order.
boolean isBigEndian = outerByteOrder == ByteOrder.BIG_ENDIAN;
bytes.order(isBigEndian ? ByteOrder.LITTLE_ENDIAN : ByteOrder.BIG_ENDIAN);
header.signature = 0x54726932;
break;
default:
throw new IllegalArgumentException("Buffer does not contain a serialized UTrie2");
}
header.options = bytes.getChar();
header.indexLength = bytes.getChar();
header.shiftedDataLength = bytes.getChar();
header.index2NullOffset = bytes.getChar();
header.dataNullOffset = bytes.getChar();
header.shiftedHighStart = bytes.getChar();
if ((header.options & UTRIE2_OPTIONS_VALUE_BITS_MASK) != 0) {
throw new IllegalArgumentException("UTrie2 serialized format error.");
}
Trie2 This;
This = new Trie2_16();
This.header = header;
/* get the length values and offsets */
This.indexLength = header.indexLength;
This.dataLength = header.shiftedDataLength << UTRIE2_INDEX_SHIFT;
This.index2NullOffset = header.index2NullOffset;
This.dataNullOffset = header.dataNullOffset;
This.highStart = header.shiftedHighStart << UTRIE2_SHIFT_1;
This.highValueIndex = This.dataLength - UTRIE2_DATA_GRANULARITY;
This.highValueIndex += This.indexLength;
// Allocate the Trie2 index array. If the data width is 16 bits, the array also
// includes the space for the data.
int indexArraySize = This.indexLength;
indexArraySize += This.dataLength;
This.index = new char[indexArraySize];
/* Read in the index */
int i;
for (i=0; i<This.indexLength; i++) {
This.index[i] = bytes.getChar();
}
/* Read in the data. 16 bit data goes in the same array as the index.
* 32 bit data goes in its own separate data array.
*/
This.data16 = This.indexLength;
for (i=0; i<This.dataLength; i++) {
This.index[This.data16 + i] = bytes.getChar();
}
This.data32 = null;
This.initialValue = This.index[This.dataNullOffset];
This.errorValue = This.index[This.data16+UTRIE2_BAD_UTF8_DATA_OFFSET];
return This;
} finally {
bytes.order(outerByteOrder);
}
}
Get the value for a code point as stored in the Trie2.
Params: - codePoint – the code point
Returns: the value
/**
* Get the value for a code point as stored in the Trie2.
*
* @param codePoint the code point
* @return the value
*/
public abstract int get(int codePoint);
Get the trie value for a UTF-16 code unit.
A Trie2 stores two distinct values for input in the lead surrogate
range, one for lead surrogates, which is the value that will be
returned by this function, and a second value that is returned
by Trie2.get().
For code units outside of the lead surrogate range, this function
returns the same result as Trie2.get().
This function, together with the alternate value for lead surrogates,
makes possible very efficient processing of UTF-16 strings without
first converting surrogate pairs to their corresponding 32 bit code point
values.
At build-time, enumerate the contents of the Trie2 to see if there
is non-trivial (non-initialValue) data for any of the supplementary
code points associated with a lead surrogate.
If so, then set a special (application-specific) value for the
lead surrogate code _unit_, with Trie2Writable.setForLeadSurrogateCodeUnit().
At runtime, use Trie2.getFromU16SingleLead(). If there is non-trivial
data and the code unit is a lead surrogate, then check if a trail surrogate
follows. If so, assemble the supplementary code point and look up its value
with Trie2.get(); otherwise reset the lead
surrogate's value or do a code point lookup for it.
If there is only trivial data for lead and trail surrogates, then processing
can often skip them. For example, in normalization or case mapping
all characters that do not have any mappings are simply copied as is.
Params: - c – the code point or lead surrogate value.
Returns: the value
/**
* Get the trie value for a UTF-16 code unit.
*
* A Trie2 stores two distinct values for input in the lead surrogate
* range, one for lead surrogates, which is the value that will be
* returned by this function, and a second value that is returned
* by Trie2.get().
*
* For code units outside of the lead surrogate range, this function
* returns the same result as Trie2.get().
*
* This function, together with the alternate value for lead surrogates,
* makes possible very efficient processing of UTF-16 strings without
* first converting surrogate pairs to their corresponding 32 bit code point
* values.
*
* At build-time, enumerate the contents of the Trie2 to see if there
* is non-trivial (non-initialValue) data for any of the supplementary
* code points associated with a lead surrogate.
* If so, then set a special (application-specific) value for the
* lead surrogate code _unit_, with Trie2Writable.setForLeadSurrogateCodeUnit().
*
* At runtime, use Trie2.getFromU16SingleLead(). If there is non-trivial
* data and the code unit is a lead surrogate, then check if a trail surrogate
* follows. If so, assemble the supplementary code point and look up its value
* with Trie2.get(); otherwise reset the lead
* surrogate's value or do a code point lookup for it.
*
* If there is only trivial data for lead and trail surrogates, then processing
* can often skip them. For example, in normalization or case mapping
* all characters that do not have any mappings are simply copied as is.
*
* @param c the code point or lead surrogate value.
* @return the value
*/
public abstract int getFromU16SingleLead(char c);
When iterating over the contents of a Trie2, Elements of this type are produced.
The iterator will return one item for each contiguous range of codepoints having the same value.
When iterating, the same Trie2EnumRange object will be reused and returned for each range.
If you need to retain complete iteration results, clone each returned Trie2EnumRange,
or save the range in some other way, before advancing to the next iteration step.
/**
* When iterating over the contents of a Trie2, Elements of this type are produced.
* The iterator will return one item for each contiguous range of codepoints having the same value.
*
* When iterating, the same Trie2EnumRange object will be reused and returned for each range.
* If you need to retain complete iteration results, clone each returned Trie2EnumRange,
* or save the range in some other way, before advancing to the next iteration step.
*/
public static class Range {
public int startCodePoint;
public int endCodePoint; // Inclusive.
public int value;
public boolean leadSurrogate;
public boolean equals(Object other) {
if (other == null || !(other.getClass().equals(getClass()))) {
return false;
}
Range tother = (Range)other;
return this.startCodePoint == tother.startCodePoint &&
this.endCodePoint == tother.endCodePoint &&
this.value == tother.value &&
this.leadSurrogate == tother.leadSurrogate;
}
public int hashCode() {
int h = initHash();
h = hashUChar32(h, startCodePoint);
h = hashUChar32(h, endCodePoint);
h = hashInt(h, value);
h = hashByte(h, leadSurrogate? 1: 0);
return h;
}
}
Create an iterator over the value ranges in this Trie2.
Values from the Trie2 are not remapped or filtered, but are returned as they
are stored in the Trie2.
Returns: an Iterator
/**
* Create an iterator over the value ranges in this Trie2.
* Values from the Trie2 are not remapped or filtered, but are returned as they
* are stored in the Trie2.
*
* @return an Iterator
*/
public Iterator<Range> iterator() {
return iterator(defaultValueMapper);
}
private static ValueMapper defaultValueMapper = new ValueMapper() {
public int map(int in) {
return in;
}
};
Create an iterator over the value ranges from this Trie2.
Values from the Trie2 are passed through a caller-supplied remapping function,
and it is the remapped values that determine the ranges that
will be produced by the iterator.
Params: - mapper – provides a function to remap values obtained from the Trie2.
Returns: an Iterator
/**
* Create an iterator over the value ranges from this Trie2.
* Values from the Trie2 are passed through a caller-supplied remapping function,
* and it is the remapped values that determine the ranges that
* will be produced by the iterator.
*
*
* @param mapper provides a function to remap values obtained from the Trie2.
* @return an Iterator
*/
public Iterator<Range> iterator(ValueMapper mapper) {
return new Trie2Iterator(mapper);
}
When iterating over the contents of a Trie2, an instance of TrieValueMapper may
be used to remap the values from the Trie2. The remapped values will be used
both in determining the ranges of codepoints and as the value to be returned
for each range.
Example of use, with an anonymous subclass of TrieValueMapper:
ValueMapper m = new ValueMapper() {
int map(int in) {return in & 0x1f;};
}
for (Iterator iter = trie.iterator(m); i.hasNext(); ) {
Trie2EnumRange r = i.next();
... // Do something with the range r.
}
/**
* When iterating over the contents of a Trie2, an instance of TrieValueMapper may
* be used to remap the values from the Trie2. The remapped values will be used
* both in determining the ranges of codepoints and as the value to be returned
* for each range.
*
* Example of use, with an anonymous subclass of TrieValueMapper:
*
*
* ValueMapper m = new ValueMapper() {
* int map(int in) {return in & 0x1f;};
* }
* for (Iterator<Trie2EnumRange> iter = trie.iterator(m); i.hasNext(); ) {
* Trie2EnumRange r = i.next();
* ... // Do something with the range r.
* }
*
*/
public interface ValueMapper {
public int map(int originalVal);
}
//--------------------------------------------------------------------------------
//
// Below this point are internal implementation items. No further public API.
//
//--------------------------------------------------------------------------------
Trie2 data structure in serialized form:
UTrie2Header header;
uint16_t index[header.index2Length];
uint16_t data[header.shiftedDataLength<<2]; -- or uint32_t data[...]
For Java, this is read from the stream into an instance of UTrie2Header.
(The C version just places a struct over the raw serialized data.)
@internal
/**
* Trie2 data structure in serialized form:
*
* UTrie2Header header;
* uint16_t index[header.index2Length];
* uint16_t data[header.shiftedDataLength<<2]; -- or uint32_t data[...]
*
* For Java, this is read from the stream into an instance of UTrie2Header.
* (The C version just places a struct over the raw serialized data.)
*
* @internal
*/
static class UTrie2Header {
"Tri2" in big-endian US-ASCII (0x54726932) /** "Tri2" in big-endian US-ASCII (0x54726932) */
int signature;
options bit field (uint16_t):
15.. 4 reserved (0)
3.. 0 UTrie2ValueBits valueBits
/**
* options bit field (uint16_t):
* 15.. 4 reserved (0)
* 3.. 0 UTrie2ValueBits valueBits
*/
int options;
UTRIE2_INDEX_1_OFFSET..UTRIE2_MAX_INDEX_LENGTH (uint16_t) /** UTRIE2_INDEX_1_OFFSET..UTRIE2_MAX_INDEX_LENGTH (uint16_t) */
int indexLength;
(UTRIE2_DATA_START_OFFSET..UTRIE2_MAX_DATA_LENGTH)>>UTRIE2_INDEX_SHIFT (uint16_t) /** (UTRIE2_DATA_START_OFFSET..UTRIE2_MAX_DATA_LENGTH)>>UTRIE2_INDEX_SHIFT (uint16_t) */
int shiftedDataLength;
Null index and data blocks, not shifted. (uint16_t) /** Null index and data blocks, not shifted. (uint16_t) */
int index2NullOffset, dataNullOffset;
First code point of the single-value range ending with U+10ffff,
rounded up and then shifted right by UTRIE2_SHIFT_1. (uint16_t)
/**
* First code point of the single-value range ending with U+10ffff,
* rounded up and then shifted right by UTRIE2_SHIFT_1. (uint16_t)
*/
int shiftedHighStart;
}
//
// Data members of UTrie2.
//
UTrie2Header header;
char index[]; // Index array. Includes data for 16 bit Tries.
int data16; // Offset to data portion of the index array, if 16 bit data.
// zero if 32 bit data.
int data32[]; // NULL if 16b data is used via index
int indexLength;
int dataLength;
int index2NullOffset; // 0xffff if there is no dedicated index-2 null block
int initialValue;
Value returned for out-of-range code points and illegal UTF-8. /** Value returned for out-of-range code points and illegal UTF-8. */
int errorValue;
/* Start of the last range which ends at U+10ffff, and its value. */
int highStart;
int highValueIndex;
int dataNullOffset;
Trie2 constants, defining shift widths, index array lengths, etc.
These are needed for the runtime macros but users can treat these as
implementation details and skip to the actual public API further below.
/**
* Trie2 constants, defining shift widths, index array lengths, etc.
*
* These are needed for the runtime macros but users can treat these as
* implementation details and skip to the actual public API further below.
*/
static final int UTRIE2_OPTIONS_VALUE_BITS_MASK=0x000f;
Shift size for getting the index-1 table offset. /** Shift size for getting the index-1 table offset. */
static final int UTRIE2_SHIFT_1=6+5;
Shift size for getting the index-2 table offset. /** Shift size for getting the index-2 table offset. */
static final int UTRIE2_SHIFT_2=5;
Difference between the two shift sizes,
for getting an index-1 offset from an index-2 offset. 6=11-5
/**
* Difference between the two shift sizes,
* for getting an index-1 offset from an index-2 offset. 6=11-5
*/
static final int UTRIE2_SHIFT_1_2=UTRIE2_SHIFT_1-UTRIE2_SHIFT_2;
Number of index-1 entries for the BMP. 32=0x20
This part of the index-1 table is omitted from the serialized form.
/**
* Number of index-1 entries for the BMP. 32=0x20
* This part of the index-1 table is omitted from the serialized form.
*/
static final int UTRIE2_OMITTED_BMP_INDEX_1_LENGTH=0x10000>>UTRIE2_SHIFT_1;
Number of entries in an index-2 block. 64=0x40 /** Number of entries in an index-2 block. 64=0x40 */
static final int UTRIE2_INDEX_2_BLOCK_LENGTH=1<<UTRIE2_SHIFT_1_2;
Mask for getting the lower bits for the in-index-2-block offset. /** Mask for getting the lower bits for the in-index-2-block offset. */
static final int UTRIE2_INDEX_2_MASK=UTRIE2_INDEX_2_BLOCK_LENGTH-1;
Number of entries in a data block. 32=0x20 /** Number of entries in a data block. 32=0x20 */
static final int UTRIE2_DATA_BLOCK_LENGTH=1<<UTRIE2_SHIFT_2;
Mask for getting the lower bits for the in-data-block offset. /** Mask for getting the lower bits for the in-data-block offset. */
static final int UTRIE2_DATA_MASK=UTRIE2_DATA_BLOCK_LENGTH-1;
Shift size for shifting left the index array values.
Increases possible data size with 16-bit index values at the cost
of compactability.
This requires data blocks to be aligned by UTRIE2_DATA_GRANULARITY.
/**
* Shift size for shifting left the index array values.
* Increases possible data size with 16-bit index values at the cost
* of compactability.
* This requires data blocks to be aligned by UTRIE2_DATA_GRANULARITY.
*/
static final int UTRIE2_INDEX_SHIFT=2;
The alignment size of a data block. Also the granularity for compaction. /** The alignment size of a data block. Also the granularity for compaction. */
static final int UTRIE2_DATA_GRANULARITY=1<<UTRIE2_INDEX_SHIFT;
The part of the index-2 table for U+D800..U+DBFF stores values for
lead surrogate code _units_ not code _points_.
Values for lead surrogate code _points_ are indexed with this portion of the table.
Length=32=0x20=0x400>>UTRIE2_SHIFT_2. (There are 1024=0x400 lead surrogates.)
/**
* The part of the index-2 table for U+D800..U+DBFF stores values for
* lead surrogate code _units_ not code _points_.
* Values for lead surrogate code _points_ are indexed with this portion of the table.
* Length=32=0x20=0x400>>UTRIE2_SHIFT_2. (There are 1024=0x400 lead surrogates.)
*/
static final int UTRIE2_LSCP_INDEX_2_OFFSET=0x10000>>UTRIE2_SHIFT_2;
static final int UTRIE2_LSCP_INDEX_2_LENGTH=0x400>>UTRIE2_SHIFT_2;
Count the lengths of both BMP pieces. 2080=0x820 /** Count the lengths of both BMP pieces. 2080=0x820 */
static final int UTRIE2_INDEX_2_BMP_LENGTH=UTRIE2_LSCP_INDEX_2_OFFSET+UTRIE2_LSCP_INDEX_2_LENGTH;
The 2-byte UTF-8 version of the index-2 table follows at offset 2080=0x820.
Length 32=0x20 for lead bytes C0..DF, regardless of UTRIE2_SHIFT_2.
/**
* The 2-byte UTF-8 version of the index-2 table follows at offset 2080=0x820.
* Length 32=0x20 for lead bytes C0..DF, regardless of UTRIE2_SHIFT_2.
*/
static final int UTRIE2_UTF8_2B_INDEX_2_OFFSET=UTRIE2_INDEX_2_BMP_LENGTH;
static final int UTRIE2_UTF8_2B_INDEX_2_LENGTH=0x800>>6; /* U+0800 is the first code point after 2-byte UTF-8 */
The index-1 table, only used for supplementary code points, at offset 2112=0x840.
Variable length, for code points up to highStart, where the last single-value range starts.
Maximum length 512=0x200=0x100000>>UTRIE2_SHIFT_1.
(For 0x100000 supplementary code points U+10000..U+10ffff.)
The part of the index-2 table for supplementary code points starts
after this index-1 table.
Both the index-1 table and the following part of the index-2 table
are omitted completely if there is only BMP data.
/**
* The index-1 table, only used for supplementary code points, at offset 2112=0x840.
* Variable length, for code points up to highStart, where the last single-value range starts.
* Maximum length 512=0x200=0x100000>>UTRIE2_SHIFT_1.
* (For 0x100000 supplementary code points U+10000..U+10ffff.)
*
* The part of the index-2 table for supplementary code points starts
* after this index-1 table.
*
* Both the index-1 table and the following part of the index-2 table
* are omitted completely if there is only BMP data.
*/
static final int UTRIE2_INDEX_1_OFFSET=UTRIE2_UTF8_2B_INDEX_2_OFFSET+UTRIE2_UTF8_2B_INDEX_2_LENGTH;
The illegal-UTF-8 data block follows the ASCII block, at offset 128=0x80.
Used with linear access for single bytes 0..0xbf for simple error handling.
Length 64=0x40, not UTRIE2_DATA_BLOCK_LENGTH.
/**
* The illegal-UTF-8 data block follows the ASCII block, at offset 128=0x80.
* Used with linear access for single bytes 0..0xbf for simple error handling.
* Length 64=0x40, not UTRIE2_DATA_BLOCK_LENGTH.
*/
static final int UTRIE2_BAD_UTF8_DATA_OFFSET=0x80;
Implementation class for an iterator over a Trie2.
Iteration over a Trie2 first returns all of the ranges that are indexed by code points,
then returns the special alternate values for the lead surrogates
@internal
/**
* Implementation class for an iterator over a Trie2.
*
* Iteration over a Trie2 first returns all of the ranges that are indexed by code points,
* then returns the special alternate values for the lead surrogates
*
* @internal
*/
class Trie2Iterator implements Iterator<Range> {
// The normal constructor that configures the iterator to cover the complete
// contents of the Trie2
Trie2Iterator(ValueMapper vm) {
mapper = vm;
nextStart = 0;
limitCP = 0x110000;
doLeadSurrogates = true;
}
The main next() function for Trie2 iterators
/**
* The main next() function for Trie2 iterators
*
*/
public Range next() {
if (!hasNext()) {
throw new NoSuchElementException();
}
if (nextStart >= limitCP) {
// Switch over from iterating normal code point values to
// doing the alternate lead-surrogate values.
doingCodePoints = false;
nextStart = 0xd800;
}
int endOfRange = 0;
int val = 0;
int mappedVal = 0;
if (doingCodePoints) {
// Iteration over code point values.
val = get(nextStart);
mappedVal = mapper.map(val);
endOfRange = rangeEnd(nextStart, limitCP, val);
// Loop once for each range in the Trie2 with the same raw (unmapped) value.
// Loop continues so long as the mapped values are the same.
for (;;) {
if (endOfRange >= limitCP-1) {
break;
}
val = get(endOfRange+1);
if (mapper.map(val) != mappedVal) {
break;
}
endOfRange = rangeEnd(endOfRange+1, limitCP, val);
}
} else {
// Iteration over the alternate lead surrogate values.
val = getFromU16SingleLead((char)nextStart);
mappedVal = mapper.map(val);
endOfRange = rangeEndLS((char)nextStart);
// Loop once for each range in the Trie2 with the same raw (unmapped) value.
// Loop continues so long as the mapped values are the same.
for (;;) {
if (endOfRange >= 0xdbff) {
break;
}
val = getFromU16SingleLead((char)(endOfRange+1));
if (mapper.map(val) != mappedVal) {
break;
}
endOfRange = rangeEndLS((char)(endOfRange+1));
}
}
returnValue.startCodePoint = nextStart;
returnValue.endCodePoint = endOfRange;
returnValue.value = mappedVal;
returnValue.leadSurrogate = !doingCodePoints;
nextStart = endOfRange+1;
return returnValue;
}
/**
*
*/
public boolean hasNext() {
return doingCodePoints && (doLeadSurrogates || nextStart < limitCP) || nextStart < 0xdc00;
}
private int rangeEndLS(char startingLS) {
if (startingLS >= 0xdbff) {
return 0xdbff;
}
int c;
int val = getFromU16SingleLead(startingLS);
for (c = startingLS+1; c <= 0x0dbff; c++) {
if (getFromU16SingleLead((char)c) != val) {
break;
}
}
return c-1;
}
//
// Iteration State Variables
//
private ValueMapper mapper;
private Range returnValue = new Range();
// The starting code point for the next range to be returned.
private int nextStart;
// The upper limit for the last normal range to be returned. Normally 0x110000, but
// may be lower when iterating over the code points for a single lead surrogate.
private int limitCP;
// True while iterating over the Trie2 values for code points.
// False while iterating over the alternate values for lead surrogates.
private boolean doingCodePoints = true;
// True if the iterator should iterate the special values for lead surrogates in
// addition to the normal values for code points.
private boolean doLeadSurrogates = true;
}
Find the last character in a contiguous range of characters with the
same Trie2 value as the input character.
Params: - c – The character to begin with.
Returns: The last contiguous character with the same value.
/**
* Find the last character in a contiguous range of characters with the
* same Trie2 value as the input character.
*
* @param c The character to begin with.
* @return The last contiguous character with the same value.
*/
int rangeEnd(int start, int limitp, int val) {
int c;
int limit = Math.min(highStart, limitp);
for (c = start+1; c < limit; c++) {
if (get(c) != val) {
break;
}
}
if (c >= highStart) {
c = limitp;
}
return c - 1;
}
//
// Hashing implementation functions. FNV hash. Respected public domain algorithm.
//
private static int initHash() {
return 0x811c9DC5; // unsigned 2166136261
}
private static int hashByte(int h, int b) {
h = h * 16777619;
h = h ^ b;
return h;
}
private static int hashUChar32(int h, int c) {
h = Trie2.hashByte(h, c & 255);
h = Trie2.hashByte(h, (c>>8) & 255);
h = Trie2.hashByte(h, c>>16);
return h;
}
private static int hashInt(int h, int i) {
h = Trie2.hashByte(h, i & 255);
h = Trie2.hashByte(h, (i>>8) & 255);
h = Trie2.hashByte(h, (i>>16) & 255);
h = Trie2.hashByte(h, (i>>24) & 255);
return h;
}
}