token.java

java1.6众多例子参考

/*
 * Copyright 1999-2002,2004,2005 The Apache Software Foundation.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.sun.org.apache.xerces.internal.impl.xpath.regex;

import java.util.Vector;
import java.util.Hashtable;

/**
 * This class represents a node in parse tree.
 * 
 * @xerces.internal
 *
 * @version $Id: Token.java,v 1.2.6.1 2005/09/06 11:46:35 neerajbj Exp $
 */
class Token implements java.io.Serializable {

    private static final long serialVersionUID = 4049923761862293040L;

    static final boolean COUNTTOKENS = true;
    static int tokens = 0;

    static final int CHAR = 0;                  // Literal char
    static final int DOT = 11;                  // .
    static final int CONCAT = 1;                // XY
    static final int UNION = 2;                 // X|Y|Z
    static final int CLOSURE = 3;               // X*
    static final int RANGE = 4;                 // [a-zA-Z] etc.
    static final int NRANGE = 5;                // [^a-zA-Z] etc.
    static final int PAREN = 6;                 // (X) or (?:X)
    static final int EMPTY = 7;                 //
    static final int ANCHOR = 8;                // ^ $ \b \B \< \> \A \Z \z
    static final int NONGREEDYCLOSURE = 9;      // *? +?
    static final int STRING = 10;               // strings
    static final int BACKREFERENCE = 12;        // back references
    static final int LOOKAHEAD = 20;            // (?=...)
    static final int NEGATIVELOOKAHEAD = 21;    // (?!...)
    static final int LOOKBEHIND = 22;           // (?<=...)
    static final int NEGATIVELOOKBEHIND = 23;   // (?<!...)
    static final int INDEPENDENT = 24;          // (?>...)
    static final int MODIFIERGROUP = 25;        // (?ims-ims:...)
    static final int CONDITION = 26;            // (?(...)yes|no)

    static final int UTF16_MAX = 0x10ffff;

    int type;

    static Token token_dot;
    static Token token_0to9;
    static Token token_wordchars;
    static Token token_not_0to9;
    static Token token_not_wordchars;
    static Token token_spaces;
    static Token token_not_spaces;
    static Token token_empty;
    static Token token_linebeginning;
    static Token token_linebeginning2;
    static Token token_lineend;
    static Token token_stringbeginning;
    static Token token_stringend;
    static Token token_stringend2;
    static Token token_wordedge;
    static Token token_not_wordedge;
    static Token token_wordbeginning;
    static Token token_wordend;
    static {
        Token.token_empty = new Token(Token.EMPTY);

        Token.token_linebeginning = Token.createAnchor('^');
        Token.token_linebeginning2 = Token.createAnchor('@');
        Token.token_lineend = Token.createAnchor('$');
        Token.token_stringbeginning = Token.createAnchor('A');
        Token.token_stringend = Token.createAnchor('z');
        Token.token_stringend2 = Token.createAnchor('Z');
        Token.token_wordedge = Token.createAnchor('b');
        Token.token_not_wordedge = Token.createAnchor('B');
        Token.token_wordbeginning = Token.createAnchor('<');
        Token.token_wordend = Token.createAnchor('>');

        Token.token_dot = new Token(Token.DOT);

        Token.token_0to9 = Token.createRange();
        Token.token_0to9.addRange('0', '9');
        Token.token_wordchars = Token.createRange();
        Token.token_wordchars.addRange('0', '9');
        Token.token_wordchars.addRange('A', 'Z');
        Token.token_wordchars.addRange('_', '_');
        Token.token_wordchars.addRange('a', 'z');
        Token.token_spaces = Token.createRange();
        Token.token_spaces.addRange('\t', '\t');
        Token.token_spaces.addRange('\n', '\n');
        Token.token_spaces.addRange('\f', '\f');
        Token.token_spaces.addRange('\r', '\r');
        Token.token_spaces.addRange(' ', ' ');

        Token.token_not_0to9 = Token.complementRanges(Token.token_0to9);
        Token.token_not_wordchars = Token.complementRanges(Token.token_wordchars);
        Token.token_not_spaces = Token.complementRanges(Token.token_spaces);
    }

    static Token.ParenToken createLook(int type, Token child) {
        if (COUNTTOKENS)  Token.tokens ++;
        return new Token.ParenToken(type, child, 0);
    }
    static Token.ParenToken createParen(Token child, int pnumber) {
        if (COUNTTOKENS)  Token.tokens ++;
        return new Token.ParenToken(Token.PAREN, child, pnumber);
    }
    static Token.ClosureToken createClosure(Token tok) {
        if (COUNTTOKENS)  Token.tokens ++;
        return new Token.ClosureToken(Token.CLOSURE, tok);
    }
    static Token.ClosureToken createNGClosure(Token tok) {
        if (COUNTTOKENS)  Token.tokens ++;
        return new Token.ClosureToken(Token.NONGREEDYCLOSURE, tok);
    }
    static Token.ConcatToken createConcat(Token tok1, Token tok2) {
        if (COUNTTOKENS)  Token.tokens ++;
        return new Token.ConcatToken(tok1, tok2);
    }
    static Token.UnionToken createConcat() {
        if (COUNTTOKENS)  Token.tokens ++;
        return new Token.UnionToken(Token.CONCAT); // *** It is not a bug.
    }
    static Token.UnionToken createUnion() {
        if (COUNTTOKENS)  Token.tokens ++;
        return new Token.UnionToken(Token.UNION);
    }
    static Token createEmpty() {
        return Token.token_empty;
    }
    static RangeToken createRange() {
        if (COUNTTOKENS)  Token.tokens ++;
        return new RangeToken(Token.RANGE);
    }
    static RangeToken createNRange() {
        if (COUNTTOKENS)  Token.tokens ++;
        return new RangeToken(Token.NRANGE);
    }
    static Token.CharToken createChar(int ch) {
        if (COUNTTOKENS)  Token.tokens ++;
        return new Token.CharToken(Token.CHAR, ch);
    }
    static private Token.CharToken createAnchor(int ch) {
        if (COUNTTOKENS)  Token.tokens ++;
        return new Token.CharToken(Token.ANCHOR, ch);
    }
    static Token.StringToken createBackReference(int refno) {
        if (COUNTTOKENS)  Token.tokens ++;
        return new Token.StringToken(Token.BACKREFERENCE, null, refno);
    }
    static Token.StringToken createString(String str) {
        if (COUNTTOKENS)  Token.tokens ++;
        return new Token.StringToken(Token.STRING, str, 0);
    }
    static Token.ModifierToken createModifierGroup(Token child, int add, int mask) {
        if (COUNTTOKENS)  Token.tokens ++;
        return new Token.ModifierToken(child, add, mask);
    }
    static Token.ConditionToken createCondition(int refno, Token condition,
                                                Token yespat, Token nopat) {
        if (COUNTTOKENS)  Token.tokens ++;
        return new Token.ConditionToken(refno, condition, yespat, nopat);
    }

    protected Token(int type) {
        this.type = type;
    }

    /**
     * A number of children.
     */
    int size() {
        return 0;
    }
    Token getChild(int index) {
        return null;
    }
    void addChild(Token tok) {
        throw new RuntimeException("Not supported.");
    }

                                                // for RANGE or NRANGE
    protected void addRange(int start, int end) {
        throw new RuntimeException("Not supported.");
    }
    protected void sortRanges() {
        throw new RuntimeException("Not supported.");
    }
    protected void compactRanges() {
        throw new RuntimeException("Not supported.");
    }
    protected void mergeRanges(Token tok) {
        throw new RuntimeException("Not supported.");
    }
    protected void subtractRanges(Token tok) {
        throw new RuntimeException("Not supported.");
    }
    protected void intersectRanges(Token tok) {
        throw new RuntimeException("Not supported.");
    }
    static Token complementRanges(Token tok) {
        return RangeToken.complementRanges(tok);
    }


    void setMin(int min) {                      // for CLOSURE
    }
    void setMax(int max) {                      // for CLOSURE
    }
    int getMin() {                              // for CLOSURE
        return -1;
    }
    int getMax() {                              // for CLOSURE
        return -1;
    }
    int getReferenceNumber() {                  // for STRING
        return 0;
    }
    String getString() {                        // for STRING
        return null;
    }

    int getParenNumber() {
        return 0;
    }
    int getChar() {
        return -1;
    }

    public String toString() {
        return this.toString(0);
    }
    public String toString(int options) {
        return this.type == Token.DOT ? "." : "";
    }

    /**
     * How many characters are needed?
     */
    final int getMinLength() {
        switch (this.type) {
          case CONCAT:
            int sum = 0;
            for (int i = 0;  i < this.size();  i ++)
                sum += this.getChild(i).getMinLength();
            return sum;

          case CONDITION:
          case UNION:
            if (this.size() == 0)
                return 0;
            int ret = this.getChild(0).getMinLength();
            for (int i = 1;  i < this.size();  i ++) {
                int min = this.getChild(i).getMinLength();
                if (min < ret)  ret = min;
            }
            return ret;

          case CLOSURE:
          case NONGREEDYCLOSURE:
            if (this.getMin() >= 0)
                return this.getMin() * this.getChild(0).getMinLength();
            return 0;

          case EMPTY:
          case ANCHOR:
            return 0;

          case DOT:
          case CHAR:
          case RANGE:
          case NRANGE:
            return 1;

          case INDEPENDENT:
          case PAREN:
          case MODIFIERGROUP:
            return this.getChild(0).getMinLength();

          case BACKREFERENCE:
            return 0;                           // *******

          case STRING:
            return this.getString().length();

          case LOOKAHEAD:
          case NEGATIVELOOKAHEAD:
          case LOOKBEHIND:
          case NEGATIVELOOKBEHIND:
            return 0;                           // ***** Really?

          default:
            throw new RuntimeException("Token#getMinLength(): Invalid Type: "+this.type);
        }
    }

    final int getMaxLength() {
        switch (this.type) {
          case CONCAT:
            int sum = 0;
            for (int i = 0;  i < this.size();  i ++) {
                int d = this.getChild(i).getMaxLength();
                if (d < 0)  return -1;
                sum += d;
            }
            return sum;

          case CONDITION:
          case UNION:
            if (this.size() == 0)
                return 0;
            int ret = this.getChild(0).getMaxLength();
            for (int i = 1;  ret >= 0 && i < this.size();  i ++) {
                int max = this.getChild(i).getMaxLength();
                if (max < 0) {                  // infinity
                    ret = -1;
                    break;
                }
                if (max > ret)  ret = max;
            }
            return ret;

          case CLOSURE:
          case NONGREEDYCLOSURE:
            if (this.getMax() >= 0)
                                                // When this.child.getMaxLength() < 0,
                                                // this returns minus value
                return this.getMax() * this.getChild(0).getMaxLength();
            return -1;

          case EMPTY:
          case ANCHOR:
            return 0;

          case CHAR:
            return 1;
          case DOT:
          case RANGE:
          case NRANGE:
            return 2;

          case INDEPENDENT:
          case PAREN:
          case MODIFIERGROUP:
            return this.getChild(0).getMaxLength();

          case BACKREFERENCE:
            return -1;                          // ******

          case STRING:
            return this.getString().length();

          case LOOKAHEAD:
          case NEGATIVELOOKAHEAD:
          case LOOKBEHIND:
          case NEGATIVELOOKBEHIND:
            return 0;                           // ***** Really?

          default:
            throw new RuntimeException("Token#getMaxLength(): Invalid Type: "+this.type);
        }
    }

    static final int FC_CONTINUE = 0;
    static final int FC_TERMINAL = 1;
    static final int FC_ANY = 2;
    private static final boolean isSet(int options, int flag) {
        return (options & flag) == flag;
    }
    final int analyzeFirstCharacter(RangeToken result, int options) {
        switch (this.type) {
          case CONCAT:
            int ret = FC_CONTINUE;
            for (int i = 0;  i < this.size();  i ++)