/*
* 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).
*
*/
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.
*
* @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.
*
* @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.
*
* @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.
*/
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.
*
* @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.
*
*
* @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<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
*/
static class UTrie2Header {
/** "Tri2" in big-endian US-ASCII (0x54726932) */
int signature;
/**
* 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) */
int indexLength;
/** (UTRIE2_DATA_START_OFFSET..UTRIE2_MAX_DATA_LENGTH)>>UTRIE2_INDEX_SHIFT (uint16_t) */
int shiftedDataLength;
/** 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)
*/
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. */
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.
*/
static final int UTRIE2_OPTIONS_VALUE_BITS_MASK=0x000f;
/** 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. */
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
*/
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.
*/
static final int UTRIE2_OMITTED_BMP_INDEX_1_LENGTH=0x10000>>UTRIE2_SHIFT_1;
/** 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. */
static final int UTRIE2_INDEX_2_MASK=UTRIE2_INDEX_2_BLOCK_LENGTH-1;
/** 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. */
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.
*/
static final int UTRIE2_INDEX_SHIFT=2;
/** 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.)
*/
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 */
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.
*/
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.
*/
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.
*/
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
*/
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
*
*/
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 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.
*
* @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;
}
}