code: protected String getContentWithoutOuterTags(XmlElement xe){
  		int indentLevel = 0;
  		StringBuilder sb = new StringBuilder();
  		Iterator<Element> iter = xe.getElements().iterator();
  		while(iter.hasNext()){
  			sb.append(iter.next().getFormattedContent(indentLevel));
  			if(iter.hasNext()){
  	            OutputUtilities.newLine(sb);				
  			}
  		}
          return sb.toString();
  	}
docs: /*
  获取xml标签内部的内容
  @author Pin Liu