IntSet.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;

public class IntSet {
    //    public static boolean DEBUG = false;
    private int[] elements = new int[0];

    public IntSet() {
    }

    private IntSet(IntSet set
    ) {
        elements = (int[]) set.elements.clone();
    }

    public void and(IntSet set
    ) {
        if (set
                == this) {
            return;
        }

        int length = 0;

        int l = 0;
        int r = 0;
        while ((l < elements.length) && (r < set.elements.length)) {
            if (elements[l] < set.elements[r]) {
                l++;
            } else if (elements[l] == set.elements[r]) {
                length++;
                l++;
                r++;
            } else {
                r++;
            }
        }

        int[] old = elements;
        elements = new int[length];

        length = l = r = 0;
        while ((l < old.length) && (r < set.elements.length)) {
            if (old[l] < set.elements[r]) {
                l++;
            } else if (old[l] == set.elements[r]) {
                elements[length++] = old[l];
                l++;
                r++;
            } else {
                r++;
            }
        }

    }

    public void clear(int bit) {
        elements = new int[0];
    }

    @Override
    public Object clone() {
        return new IntSet(this);
    }

    @Override
    public boolean equals(Object obj) {
        if (obj == null) {
            return false;
        }

        if (!(obj instanceof IntSet)) {
            return false;
        }

        IntSet set
                = (IntSet) obj;

        if (elements.length != set.elements.length) {
            return false;
        }

        for (int i = 0; i < elements.length; i++) {
            if (elements[i] != set.elements[i]) {
                return false;
            }
        }

        return true;
    }

    public boolean get
            (int bit) {
        int low = 0;
        int high = elements.length - 1;

        while (low <= high) {
            int middle = (low + high) / 2;

            if (bit < elements[middle]) {
                high = middle - 1;
            } else if (bit == elements[middle]) {
                return true;
            } else {
                low = middle + 1;
            }
        }

        return false;
    }

    @Override
    public int hashCode() {
        int result = 0;

        for (int i = 0; i < elements.length; i++) {
            result += elements[i];
        }

        return result;
    }

    public void or(IntSet set
    ) {
        if (set
                == this) {
            return;
        }

        //        if(DEBUG)
        //        {
        //            System.out.println(
        //            " elements.length:" + elements.length +
        //            " set.elements.length:" + set.elements.length);
        //        }

        int length = 0;

        int l = 0;
        int r = 0;
        while ((l < elements.length) || (r < set.elements.length)) {
            //            if(DEBUG)
            //            {
            //                System.out.println(
            //                " l:" + l +
            //                " r:" + r +
            //                " length:" + length);
            //            }

            if ((r == set.elements.length) ||
                    ((l != elements.length) && (elements[l] < set.elements[r]))) {
                length++;
                l++;
            } else if ((l == elements.length) ||
                    (elements[l] > set.elements[r])) {
                length++;
                r++;
            } else {
                length++;
                l++;
                r++;
            }
        }

        int[] old = elements;
        elements = new int[length];

        length = l = r = 0;
        while ((l < old.length) || (r < set.elements.length)) {
            //            if(DEBUG)
            //            {
            //                System.out.println(
            //                " l:" + l +
            //                " r:" + r +
            //                " length:" + length);
            //            }

            if ((r == set.elements.length) ||
                    ((l != old.length) && (old[l] < set.elements[r]))) {
                elements[length++] = old[l];
                l++;
            } else if ((l == old.length) ||
                    (old[l] > set.elements[r])) {
                elements[length++] = set.elements[r];
                r++;
            } else {
                elements[length++] = old[l];
                l++;
                r++;
            }
        }

    }

    public void set
            (int bit) {
        if (!get
                (bit)) {
            int[] old = elements;
            elements = new int[old.length + 1];

            int old_pos = 0;
            boolean bit_inserted = false;
            int pos = 0;

            while (pos < elements.length) {
                if (!bit_inserted) {
                    if (old_pos < old.length) {
                        if (bit < old[old_pos]) {
                            elements[pos++] = bit;
                            bit_inserted = true;
                        } else {
                            elements[pos++] = old[old_pos++];
                        }
                    } else {
                        elements[pos++] = bit;
                        bit_inserted = true;
                    }
                } else {
                    elements[pos++] = old[old_pos++];
                }
            }
        }
    }

    public int size() {
        if (elements.length == 0) {
            return 0;
        }

        return elements[elements.length - 1] + 1;
    }

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

        s.append("{");

        boolean comma = false;

        for (int i = 0; i < elements.length; i++) {
            if (comma) {
                s.append(", ");
            } else {
                comma = true;
            }

            s.append(elements[i]);
        }
        s.append("}");

        return s.toString();
    }

    public void xor(IntSet set
    ) {
        if (set
                == this) {
            set
                    = (IntSet) set.clone();
        }

        int length = 0;
        int l = 0;
        int r = 0;

        while ((l < elements.length) || (r < set.elements.length)) {
            if ((r == set.elements.length) ||
                    ((l != elements.length) && (elements[l] < set.elements[r]))) {
                length++;
                l++;
            } else if ((l == elements.length) ||
                    (elements[l] > set.elements[r])) {
                length++;
                r++;
            } else {
                l++;
                r++;
            }
        }

        int[] old = elements;
        elements = new int[length];

        length = l = r = 0;
        while ((l < old.length) || (r < set.elements.length)) {
            if ((r == set.elements.length) ||
                    ((l != old.length) && (old[l] < set.elements[r]))) {
                elements[length++] = old[l];
                l++;
            } else if ((l == old.length) ||
                    (old[l] > set.elements[r])) {
                elements[length++] = set.elements[r];
                r++;
            } else {
                l++;
                r++;
            }
        }
    }

    public int[] elements() {
        return (int[]) elements/*.clone()*/;
    }
}