com.ibm.icu.text.RBBISetBuilder Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of icu4j Show documentation
Show all versions of icu4j Show documentation
International Component for Unicode for Java (ICU4J) is a mature, widely used Java library
providing Unicode and Globalization support
// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html#License
/*
*******************************************************************************
* Copyright (C) 2003-2011, International Business Machines Corporation and *
* others. All Rights Reserved. *
*******************************************************************************
*/
package com.ibm.icu.text;
import java.io.IOException;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.List;
import com.ibm.icu.impl.Assert;
import com.ibm.icu.impl.Trie2Writable;
import com.ibm.icu.impl.Trie2_16;
import com.ibm.icu.text.RBBIRuleBuilder.IntPair;
//
// RBBISetBuilder Handles processing of Unicode Sets from RBBI rules
// (part of the rule building process.)
//
// Starting with the rules parse tree from the scanner,
//
// - Enumerate the set of UnicodeSets that are referenced
// by the RBBI rules.
// - compute a set of non-overlapping character ranges
// with all characters within a range belonging to the same
// set of input uniocde sets.
// - Derive a set of non-overlapping UnicodeSet (like things)
// that will correspond to columns in the state table for
// the RBBI execution engine. All characters within one
// of these sets belong to the same set of the original
// UnicodeSets from the user's rules.
// - construct the trie table that maps input characters
// to the index of the matching non-overlapping set of set from
// the previous step.
//
class RBBISetBuilder {
static class RangeDescriptor {
int fStartChar; // Start of range, unicode 32 bit value.
int fEndChar; // End of range, unicode 32 bit value.
int fNum; // runtime-mapped input value for this range.
List fIncludesSets; // vector of the the original
// Unicode sets that include this range.
// (Contains ptrs to uset nodes)
RangeDescriptor fNext; // Next RangeDescriptor in the linked list.
RangeDescriptor() {
fIncludesSets = new ArrayList();
}
RangeDescriptor(RangeDescriptor other) {
fStartChar = other.fStartChar;
fEndChar = other.fEndChar;
fNum = other.fNum;
fIncludesSets = new ArrayList(other.fIncludesSets);
}
//-------------------------------------------------------------------------------------
//
// RangeDesriptor::split()
//
//-------------------------------------------------------------------------------------
void split(int where) {
Assert.assrt(where>fStartChar && where<=fEndChar);
RangeDescriptor nr = new RangeDescriptor(this);
// RangeDescriptor copy constructor copies all fields.
// Only need to update those that are different after the split.
nr.fStartChar = where;
this.fEndChar = where-1;
nr.fNext = this.fNext;
this.fNext = nr;
// TODO: fIncludesSets is not updated. Check it out.
// Probably because they haven't been populated yet,
// but still sloppy.
}
//-------------------------------------------------------------------------------------
//
// RangeDescriptor::setDictionaryFlag
//
// Character Category Numbers that include characters from
// the original Unicode Set named "dictionary" have bit 14
// set to 1. The RBBI runtime engine uses this to trigger
// use of the word dictionary.
//
// This function looks through the Unicode Sets that it
// (the range) includes, and sets the bit in fNum when
// "dictionary" is among them.
//
// TODO: a faster way would be to find the set node for
// "dictionary" just once, rather than looking it
// up by name every time.
//
// -------------------------------------------------------------------------------------
void setDictionaryFlag() {
int i;
for (i=0; i=0) {printSets();}
// Initialize the process by creating a single range encompassing all characters
// that is in no sets.
//
fRangeList = new RangeDescriptor();
fRangeList.fStartChar = 0;
fRangeList.fEndChar = 0x10ffff;
//
// Find the set of non-overlapping ranges of characters
//
for (RBBINode usetNode : fRB.fUSetNodes) {
UnicodeSet inputSet = usetNode.fInputSet;
int inputSetRangeCount = inputSet.getRangeCount();
int inputSetRangeIndex = 0;
rlRange = fRangeList;
for (;;) {
if (inputSetRangeIndex >= inputSetRangeCount) {
break;
}
int inputSetRangeBegin = inputSet.getRangeStart(inputSetRangeIndex);
int inputSetRangeEnd = inputSet.getRangeEnd(inputSetRangeIndex);
// skip over ranges from the range list that are completely
// below the current range from the input unicode set.
while (rlRange.fEndChar < inputSetRangeBegin) {
rlRange = rlRange.fNext;
}
// If the start of the range from the range list is before with
// the start of the range from the unicode set, split the range list range
// in two, with one part being before (wholly outside of) the unicode set
// and the other containing the rest.
// Then continue the loop; the post-split current range will then be skipped
// over
if (rlRange.fStartChar < inputSetRangeBegin) {
rlRange.split(inputSetRangeBegin);
continue;
}
// Same thing at the end of the ranges...
// If the end of the range from the range list doesn't coincide with
// the end of the range from the unicode set, split the range list
// range in two. The first part of the split range will be
// wholly inside the Unicode set.
if (rlRange.fEndChar > inputSetRangeEnd) {
rlRange.split(inputSetRangeEnd+1);
}
// The current rlRange is now entirely within the UnicodeSet range.
// Add this unicode set to the list of sets for this rlRange
if (rlRange.fIncludesSets.indexOf(usetNode) == -1) {
rlRange.fIncludesSets.add(usetNode);
}
// Advance over ranges that we are finished with.
if (inputSetRangeEnd == rlRange.fEndChar) {
inputSetRangeIndex++;
}
rlRange = rlRange.fNext;
}
}
if (fRB.fDebugEnv!=null && fRB.fDebugEnv.indexOf("range")>=0) { printRanges();}
//
// Group the above ranges, with each group consisting of one or more
// ranges that are in exactly the same set of original UnicodeSets.
// The groups are numbered, and these group numbers are the set of
// input symbols recognized by the run-time state machine.
//
// Numbering: # 0 (state table column 0) is unused.
// # 1 is reserved - table column 1 is for end-of-input
// # 2 is reserved - table column 2 is for beginning-in-input
// # 3 is the first range list.
//
RangeDescriptor rlSearchRange;
for (rlRange = fRangeList; rlRange!=null; rlRange=rlRange.fNext) {
for (rlSearchRange=fRangeList; rlSearchRange != rlRange; rlSearchRange=rlSearchRange.fNext) {
if (rlRange.fIncludesSets.equals(rlSearchRange.fIncludesSets)) {
rlRange.fNum = rlSearchRange.fNum;
break;
}
}
if (rlRange.fNum == 0) {
fGroupCount ++;
rlRange.fNum = fGroupCount+2;
rlRange.setDictionaryFlag();
addValToSets(rlRange.fIncludesSets, fGroupCount+2);
}
}
// Handle input sets that contain the special string {eof}.
// Column 1 of the state table is reserved for EOF on input.
// Column 2 is reserved for before-the-start-input.
// (This column can be optimized away later if there are no rule
// references to {bof}.)
// Add this column value (1 or 2) to the equivalent expression
// subtree for each UnicodeSet that contains the string {eof}
// Because {bof} and {eof} are not a characters in the normal sense,
// they doesn't affect the computation of ranges or TRIE.
String eofString = "eof";
String bofString = "bof";
for (RBBINode usetNode : fRB.fUSetNodes) {
UnicodeSet inputSet = usetNode.fInputSet;
if (inputSet.contains(eofString)) {
addValToSet(usetNode, 1);
}
if (inputSet.contains(bofString)) {
addValToSet(usetNode, 2);
fSawBOF = true;
}
}
if (fRB.fDebugEnv!=null && fRB.fDebugEnv.indexOf("rgroup")>=0) {printRangeGroups();}
if (fRB.fDebugEnv!=null && fRB.fDebugEnv.indexOf("esets")>=0) {printSets();}
}
/**
* Build the Trie table for mapping UChar32 values to the corresponding
* range group number.
*/
void buildTrie() {
RangeDescriptor rlRange;
fTrie = new Trie2Writable(0, // Initial value for all code points.
0); // Error value for out-of-range input.
for (rlRange = fRangeList; rlRange!=null; rlRange=rlRange.fNext) {
fTrie.setRange(
rlRange.fStartChar, // Range start
rlRange.fEndChar, // Range end (inclusive)
rlRange.fNum, // value for range
true // Overwrite previously written values
);
}
}
/**
* Merge two character categories that have been identified as having equivalent behavior.
* The ranges belonging to the second category (table column) will be added to the first.
* @param categories the pair of categories to be merged.
*/
void mergeCategories(IntPair categories) {
assert(categories.first >= 1);
assert(categories.second > categories.first);
for (RangeDescriptor rd = fRangeList; rd != null; rd = rd.fNext) {
int rangeNum = rd.fNum & ~DICT_BIT;
int rangeDict = rd.fNum & DICT_BIT;
if (rangeNum == categories.second) {
rd.fNum = categories.first | rangeDict;
} else if (rangeNum > categories.second) {
rd.fNum--;
}
}
--fGroupCount;
}
//-----------------------------------------------------------------------------------
//
// getTrieSize() Return the size that will be required to serialize the Trie.
//
//-----------------------------------------------------------------------------------
int getTrieSize() {
if (fFrozenTrie == null) {
fFrozenTrie = fTrie.toTrie2_16();
fTrie = null;
}
return fFrozenTrie.getSerializedLength();
}
//-----------------------------------------------------------------------------------
//
// serializeTrie() Write the serialized trie to an output stream
//
//-----------------------------------------------------------------------------------
void serializeTrie(OutputStream os) throws IOException {
if (fFrozenTrie == null) {
fFrozenTrie = fTrie.toTrie2_16();
fTrie = null;
}
fFrozenTrie.serialize(os);
}
//------------------------------------------------------------------------
//
// addValToSets Add a runtime-mapped input value to each uset from a
// list of uset nodes. (val corresponds to a state table column.)
// For each of the original Unicode sets - which correspond
// directly to uset nodes - a logically equivalent expression
// is constructed in terms of the remapped runtime input
// symbol set. This function adds one runtime input symbol to
// a list of sets.
//
// The "logically equivalent expression" is the tree for an
// or-ing together of all of the symbols that go into the set.
//
//------------------------------------------------------------------------
void addValToSets(List sets, int val) {
for (RBBINode usetNode : sets) {
addValToSet(usetNode, val);
}
}
void addValToSet(RBBINode usetNode, int val) {
RBBINode leafNode = new RBBINode(RBBINode.leafChar);
leafNode.fVal = val;
if (usetNode.fLeftChild == null) {
usetNode.fLeftChild = leafNode;
leafNode.fParent = usetNode;
} else {
// There are already input symbols present for this set.
// Set up an OR node, with the previous stuff as the left child
// and the new value as the right child.
RBBINode orNode = new RBBINode(RBBINode.opOr);
orNode.fLeftChild = usetNode.fLeftChild;
orNode.fRightChild = leafNode;
orNode.fLeftChild.fParent = orNode;
orNode.fRightChild.fParent = orNode;
usetNode.fLeftChild = orNode;
orNode.fParent = usetNode;
}
}
//------------------------------------------------------------------------
//
// getNumCharCategories
//
//------------------------------------------------------------------------
int getNumCharCategories() {
return fGroupCount + 3;
}
//------------------------------------------------------------------------
//
// sawBOF
//
//------------------------------------------------------------------------
boolean sawBOF() {
return fSawBOF;
}
//------------------------------------------------------------------------
//
// getFirstChar Given a runtime RBBI character category, find
// the first UChar32 that is in the set of chars
// in the category.
//------------------------------------------------------------------------
int getFirstChar(int category) {
RangeDescriptor rlRange;
int retVal = -1;
for (rlRange = fRangeList; rlRange!=null; rlRange=rlRange.fNext) {
if (rlRange.fNum == category) {
retVal = rlRange.fStartChar;
break;
}
}
return retVal;
}
//------------------------------------------------------------------------
//
// printRanges A debugging function.
// dump out all of the range definitions.
//
//------------------------------------------------------------------------
///CLOVER:OFF
void printRanges() {
RangeDescriptor rlRange;
int i;
System.out.print("\n\n Nonoverlapping Ranges ...\n");
for (rlRange = fRangeList; rlRange!=null; rlRange=rlRange.fNext) {
System.out.print(" " + rlRange.fNum + " " + rlRange.fStartChar + "-" + rlRange.fEndChar);
for (i=0; i lastPrintedGroupNum) {
lastPrintedGroupNum = groupNum;
if (groupNum<10) {System.out.print(" ");}
System.out.print(groupNum + " ");
if ((rlRange.fNum & DICT_BIT) != 0) { System.out.print(" ");}
for (i=0; i