public void sub()

in jflex/src/main/java/jflex/core/unicode/IntCharSet.java [365:439]

• 55 lines of code
• 12 McCabe index (conditional complexity)

  public void sub(IntCharSet set) {
    if (DEBUG) {
      Out.dump("complement");
      Out.dump("this  : " + this);
      Out.dump("other : " + set);
      assert invariants();
      // not asserting non-null, because we'll already get an exception and it confuses lgtm.com
      assert set.invariants();
      assert isSubSet(set, this);
      assert set != this; // reference comparison intended, must supply different object
    }

    int i = 0; // index in this.intervals
    int j = 0; // index in set.intervals

    int setSize = set.intervals.size();

    while (i < intervals.size() && j < setSize) {
      Interval x = this.intervals.get(i);
      Interval y = set.intervals.get(j);

      if (DEBUG) {
        Out.dump("this      : " + this);
        Out.dump("this  [" + i + "] : " + x);
        Out.dump("other [" + j + "] : " + y);
      }

      if (x.end < y.start) {
        i++;
        continue;
      }

      if (y.end < x.start) {
        j++;
        continue;
      }

      // x.end >= y.start && y.end >= x.start ->
      // x.end <= y.end && x.start >= y.start (prec)

      if (x.start == y.start && x.end == y.end) {
        intervals.remove(i);
        j++;
        continue;
      }

      // x.end <= y.end && x.start >= y.start &&
      // (x.end < y.end || x.start > y.start) ->
      // x.start < x.end

      if (x.start == y.start) {
        x.start = y.end + 1;
        j++;
        continue;
      }

      if (x.end == y.end) {
        x.end = y.start - 1;
        i++;
        j++;
        continue;
      }

      intervals.add(i, new Interval(x.start, y.start - 1));
      x.start = y.end + 1;

      i++;
      j++;
    }

    if (DEBUG) {
      Out.dump("result: " + this);
      assert invariants();
    }
  }