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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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package jdk.nashorn.internal.runtime.regexp;

import java.util.regex.MatchResult;
import jdk.nashorn.internal.runtime.BitVector;
import jdk.nashorn.internal.runtime.ECMAErrors;
import jdk.nashorn.internal.runtime.ParserException;

This is the base class for representing a parsed regular expression. Instances of this class are created by a RegExpFactory. /**
 * This is the base class for representing a parsed regular expression.
 *
 * Instances of this class are created by a {@link RegExpFactory}.
 */
public abstract class RegExp {

    
Pattern string. /** Pattern string. */
    private final String source;

    
Global search flag for this regexp./** Global search flag for this regexp.*/
    private boolean global;

    
Case insensitive flag for this regexp /** Case insensitive flag for this regexp */
    private boolean ignoreCase;

    
Multi-line flag for this regexp /** Multi-line flag for this regexp */
    private boolean multiline;

    
BitVector that keeps track of groups in negative lookahead /** BitVector that keeps track of groups in negative lookahead */
    protected BitVector groupsInNegativeLookahead;

    
Constructor.
Params:
source – the source string
flags – the flags string/**
     * Constructor.
     *
     * @param source the source string
     * @param flags the flags string
     */
    protected RegExp(final String source, final String flags) {
        this.source = source.length() == 0 ? "(?:)" : source;
        for (int i = 0; i < flags.length(); i++) {
            final char ch = flags.charAt(i);
            switch (ch) {
            case 'g':
                if (this.global) {
                    throwParserException("repeated.flag", "g");
                }
                this.global = true;
                break;
            case 'i':
                if (this.ignoreCase) {
                    throwParserException("repeated.flag", "i");
                }
                this.ignoreCase = true;
                break;
            case 'm':
                if (this.multiline) {
                    throwParserException("repeated.flag", "m");
                }
                this.multiline = true;
                break;
            default:
                throwParserException("unsupported.flag", Character.toString(ch));
            }
        }
    }

    
Get the source pattern of this regular expression.
Returns:
the source string/**
     * Get the source pattern of this regular expression.
     *
     * @return the source string
     */
    public String getSource() {
        return source;
    }

    
Set the global flag of this regular expression to global. 
Params:
global – the new global flag/**
     * Set the global flag of this regular expression to {@code global}.
     *
     * @param global the new global flag
     */
    public void setGlobal(final boolean global) {
        this.global = global;
    }

    
Get the global flag of this regular expression.
Returns:
the global flag/**
     * Get the global flag of this regular expression.
     *
     * @return the global flag
     */
    public boolean isGlobal() {
        return global;
    }

    
Get the ignore-case flag of this regular expression.
Returns:
the ignore-case flag/**
     * Get the ignore-case flag of this regular expression.
     *
     * @return the ignore-case flag
     */
    public boolean isIgnoreCase() {
        return ignoreCase;
    }

    
Get the multiline flag of this regular expression.
Returns:
the multiline flag/**
     * Get the multiline flag of this regular expression.
     *
     * @return the multiline flag
     */
    public boolean isMultiline() {
        return multiline;
    }

    
Get a bitset indicating which of the groups in this regular expression are inside a negative lookahead.
Returns:
the groups-in-negative-lookahead bitset/**
     * Get a bitset indicating which of the groups in this regular expression are inside a negative lookahead.
     *
     * @return the groups-in-negative-lookahead bitset
     */
    public BitVector getGroupsInNegativeLookahead() {
        return groupsInNegativeLookahead;
    }

    
Match this regular expression against str, starting at index start and return a MatchResult with the result. 
Params:
str – the string
Returns:
the matcher/**
     * Match this regular expression against {@code str}, starting at index {@code start}
     * and return a {@link MatchResult} with the result.
     *
     * @param str the string
     * @return the matcher
     */
    public abstract RegExpMatcher match(String str);

    
Throw a regexp parser exception.
Params:
key – the message key
str – string argument
Throws:
ParserException – unconditionally/**
     * Throw a regexp parser exception.
     *
     * @param key the message key
     * @param str string argument
     * @throws jdk.nashorn.internal.runtime.ParserException unconditionally
     */
    protected static void throwParserException(final String key, final String str) throws ParserException {
        throw new ParserException(ECMAErrors.getMessage("parser.error.regex." + key, str));
    }
}