LR0Collection.java

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * This file is part of SableCC.                             *
 * See the file "LICENSE" for copyright information and the  *
 * terms and conditions for copying, distribution and        *
 * modification of SableCC.                                  *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

package org.sablecc.sablecc;

import java.util.TreeMap;
import java.util.Vector;

@SuppressWarnings({"rawtypes", "unchecked"})
final class LR0Collection {
    private final Vector sets = new Vector(0);
    private final TreeMap setIndices = new TreeMap();
    private final Vector GOTO = new Vector(0);
    final Vector names = new Vector(0);

    LR0Collection(LR0ItemSet set
    ) {
        add
                (set
                        , -1, null);

        for (int i = 0; i < sets.size(); i++) {
            System.out.print(".");
            Symbol[] symbols = Symbol.symbols();

            for (int j = 0; j < symbols.length; j++) {
                addGoto(i, symbols[j], Grammar.GOTO(set
                        (i), symbols[j]));
            }
        }
        System.out.println();
    }

    private int add
            (LR0ItemSet set
                    , int from, Symbol symbol) {
        Integer result = set
                (set
                );

        if (result == null) {
            result = new Integer(sets.size());

            setIndices.put(set
                    , result);
            sets.addElement(set
            );
            GOTO.addElement(new TreeMap());
            if (from == -1) {
                names.addElement(" ");
            } else {
                names.addElement(names.elementAt(from) + "" + symbol + " ");
            }
        }

        return result.intValue();
    }

    private static LR0ItemSet empty = new LR0ItemSet();

    public static void reinit() {
        empty = new LR0ItemSet();
    }

    private void addGoto(int from, Symbol symbol, LR0ItemSet to) {
        if (!to.equals(empty)) {
            ((TreeMap) GOTO.elementAt(from)).put(symbol, new Integer(add
                    (to, from, symbol)));
        }
    }

    private Integer set
            (LR0ItemSet set
            ) {
        return (Integer) setIndices.get(set
        );
    }

    private LR0ItemSet set
            (int index) {
        return (LR0ItemSet) sets.elementAt(index);
    }

    LR0ItemSet[] sets() {
        LR0ItemSet[] result = new LR0ItemSet[sets.size()];
        sets.copyInto(result);

        return result;
    }

    Integer GOTO(int set
            , Symbol symbol) {
        return (Integer) ((TreeMap) GOTO.elementAt(set
        )).get(symbol);
    }

    @Override
    public String toString() {
        StringBuffer result = new StringBuffer();

        result.append("{[LR0ItemCollection]" + System.getProperty("line.separator"));
        LR0ItemSet[] sets = sets();
        Symbol[] symbols = Symbol.symbols();

        for (int i = 0; i < sets.length; i++) {
            result.append(i + ":" + Grammar.CLOSURE(sets[i]));
            result.append(System.getProperty("line.separator"));

            for (int j = 0; j < symbols.length; j++) {
                if (GOTO(i, symbols[j]) != null) {
                    result.append("[");
                    result.append(symbols[j]);
                    result.append(":");
                    result.append(GOTO(i, symbols[j]));
                    result.append("]");
                }
            }

            result.append(System.getProperty("line.separator"));
        }

        result.append("}");
        return result.toString();
    }
}