コード例 #1
0
ファイル: Data.java プロジェクト: JosuaKrause/basex
  /**
   * Deletes a node and its descendants.
   *
   * @param pre pre value of the node to delete
   */
  public final void delete(final int pre) {
    meta.update();

    // size of the subtree to delete
    int k = kind(pre);
    final int s = size(pre, k);
    resources.delete(pre, s);

    if (meta.updindex) {
      // delete child records from indexes
      indexDelete(pre, s);
    }

    /// explicitly delete text or attribute value
    if (k != DOC && k != ELEM) delete(pre, k != ATTR);

    // reduce size of ancestors
    int par = pre;
    // check if we are an attribute (different size counters)
    if (k == ATTR) {
      par = parent(par, ATTR);
      attSize(par, ELEM, attSize(par, ELEM) - 1);
      size(par, ELEM, size(par, ELEM) - 1);
      k = kind(par);
    }

    // reduce size of ancestors
    while (par > 0 && k != DOC) {
      par = parent(par, k);
      k = kind(par);
      size(par, k, size(par, k) - s);
    }

    // preserve empty root node
    if (kind(pre) == DOC) --meta.ndocs;

    if (meta.updindex) {
      // delete node and descendants from ID -> PRE map:
      idmap.delete(pre, id(pre), -s);
    }

    // delete node from table structure and reduce document size
    table.delete(pre, s);

    if (!cache) updateDist(pre, -s);

    // propagate PRE value shifts to namespaces
    nspaces.delete(pre, s, this);
  }
コード例 #2
0
ファイル: Data.java プロジェクト: JosuaKrause/basex
  /**
   * Replaces parts of the database with the specified data instance.
   *
   * @param rpre pre value to be replaced
   * @param clip data clip
   */
  public final void replace(final int rpre, final DataClip clip) {
    meta.update();

    final int dsize = clip.size();
    final Data data = clip.data;

    final int rkind = kind(rpre);
    final int rsize = size(rpre, rkind);
    final int rpar = parent(rpre, rkind);
    final int diff = dsize - rsize;
    buffer(dsize);
    resources.replace(rpre, rsize, clip);

    if (meta.updindex) {
      // update index
      indexDelete(rpre, rsize);
      indexBegin();
    }

    for (int dpre = clip.start; dpre < clip.end; ++dpre) {
      final int dkind = data.kind(dpre);
      final int dpar = data.parent(dpre, dkind);
      final int pre = rpre + dpre - clip.start;
      final int dis = dpar >= 0 ? dpre - dpar : pre - rpar;

      switch (dkind) {
        case DOC:
          // add document
          doc(pre, data.size(dpre, dkind), data.text(dpre, true));
          meta.ndocs++;
          break;
        case ELEM:
          // add element
          byte[] nm = data.name(dpre, dkind);
          elem(
              dis,
              tagindex.index(nm, null, false),
              data.attSize(dpre, dkind),
              data.size(dpre, dkind),
              nspaces.uri(nm, true),
              false);
          break;
        case TEXT:
        case COMM:
        case PI:
          // add text
          text(pre, dis, data.text(dpre, true), dkind);
          break;
        case ATTR:
          // add attribute
          nm = data.name(dpre, dkind);
          attr(
              pre,
              dis,
              atnindex.index(nm, null, false),
              data.text(dpre, false),
              nspaces.uri(nm, false),
              false);
          break;
      }
    }

    if (meta.updindex) {
      indexEnd();
      // update ID -> PRE map:
      idmap.delete(rpre, id(rpre), -rsize);
      idmap.insert(rpre, meta.lastid - dsize + 1, dsize);
    }

    // update table:
    table.replace(rpre, buffer(), rsize);
    buffer(1);

    // no distance/size update if the two subtrees are of equal size
    if (diff == 0) return;

    // increase/decrease size of ancestors, adjust distances of siblings
    int p = rpar;
    while (p >= 0) {
      final int k = kind(p);
      size(p, k, size(p, k) + diff);
      p = parent(p, k);
    }

    if (!cache) updateDist(rpre + dsize, diff);

    // adjust attribute size of parent if attributes inserted. attribute size
    // of parent cannot be reduced via a replace expression.
    int dpre = clip.start;
    if (data.kind(dpre) == ATTR) {
      int d = 0;
      while (dpre < clip.end && data.kind(dpre++) == ATTR) d++;
      if (d > 1) attSize(rpar, kind(rpar), d + 1);
    }
  }