paxGname    = "gname"
	paxMtime    = "mtime"
	paxAtime    = "atime"
	paxCtime    = "ctime"   // Removed from later revision of PAX spec, but was valid
	paxCharset  = "charset" // Currently unused
	paxComment  = "comment" // Currently unused

	paxSchilyXattr = "SCHILY.xattr."

	// Keywords for GNU sparse files in a PAX extended header.
	paxGNUSparse          = "GNU.sparse."
	paxGNUSparseNumBlocks = "GNU.sparse.numblocks"

      this.right = null;
    }

    /** Constructor for the header node. */
    AvlNode() {
      this.elem = null;
      this.elemCount = 1;
    }

    // For discussion of pred() and succ(), see the comment on the pred and succ fields.

    private AvlNode<E> pred() {
      return requireNonNull(pred);
    }

    private AvlNode<E> succ() {
      return requireNonNull(succ);
    }

      boilerplate notice, with the fields enclosed by brackets "[]"
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      boilerplate notice, with the fields enclosed by brackets "[]"
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      boilerplate notice, with the fields enclosed by brackets "[]"
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      boilerplate notice, with the fields enclosed by brackets "{}"
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      boilerplate notice, with the fields enclosed by brackets "{}"
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