public void selectElement_P(String en) {
protected void selectElement_P(String en) { if (en == null) throw new IllegalArgumentException("element name can't be null");
public void selectElement_P(String en) {	depth = vn.getCurrentDepth();	iter_type = PRECEDING;    ft = true;	    name = en;    contextCopy = (int[])vn.context.clone();    contextCopy[0]=vn.rootIndex;}