code: protected void parseIf() {
  		String condition = tokenizer.getToken().substring(2);
  		if (StringUtils.isBlank(condition)) {
  			throw new IfConditionNotFoundRuntimeException();
  		}
  		IfNode ifNode = new IfNode(Math.max(this.position - 2, 0), condition);
  		this.position = this.tokenizer.getPosition();
  		peek().addChild(ifNode);
  		push(ifNode);
  		parseEnd();
  	}
docs: IF文解析