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Internal package of Alachisoft.
There is a newer version: 5.3.3
package Alachisoft.NCache.Parser;

// C# Translation of GoldParser, by Marcus Klimstra .
// Based on GOLDParser by Devin Cook .

/**
 * The Rule class is used to represent the logical structures of the grammar.
 * Rules consist of a head containing a nonterminal followed by a series of
 * both nonterminals and terminals.
 */
public class Rule {
    private Symbol m_ruleNT; // non-terminal rule
    private java.util.ArrayList m_ruleSymbols;
    private int m_tableIndex;

    /* constructor */

    /**
     * Creates a new Rule.
     */
    public Rule(int p_tableIndex, Symbol p_head) {
        m_ruleSymbols = new java.util.ArrayList();
        m_tableIndex = p_tableIndex;
        m_ruleNT = p_head;
    }

    /* public properties */

    /**
     * Gets the index of this Rule in the GoldParser's rule-table.
     */
    public final int getTableIndex() {
        return m_tableIndex;
    }

    /**
     * Gets the head symbol of this rule.
     */
    public final Symbol getRuleNonTerminal() {
        return m_ruleNT;
    }

    /**
     * Gets the number of symbols in the body (right-hand-side) of the rule.
     */
    public final int getSymbolCount() {
        return m_ruleSymbols.size();
    }

    /* internal properties */

    /**
     * The name of this rule.
     */
    public final String getName() {
        return "<" + m_ruleNT.getName() + ">";
    }

    /**
     * The definition of this rule.
     */
    public final String getDefinition() {
        StringBuilder result = new StringBuilder();
        java.util.Iterator enumerator = m_ruleSymbols.iterator();

        while (enumerator.hasNext()) {
            Symbol symbol = (Symbol) enumerator.next();
            result.append(symbol.toString()).append(" ");
        }

        return result.toString();
    }

    /**
     *
     */
    public final boolean getContainsOneNonTerminal() {
        return m_ruleSymbols.size() == 1 && ((Symbol) m_ruleSymbols.get(0)).getKind().getValue() == 0;
    }

    /* public methods */

    /**
     * Returns the symbol in the body of the rule with the specified index.
     */
    public final Symbol GetSymbol(int p_index) {
        if (p_index >= 0 && p_index < m_ruleSymbols.size()) {
            return (Symbol) m_ruleSymbols.get(p_index);
        } else {
            return null;
        }
    }

    /**
     * Returns the Backus-Noir representation of this Rule.
     */
    @Override
    public String toString() {
        return getName() + " ::= " + getDefinition();
    }

    // equals ?

    /**
     *
     */
    public final void AddItem(Symbol p_symbol) {
        m_ruleSymbols.add(p_symbol);
    }
}