XPath查询结果不显示

package com.imooc.plan;

import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.Node;
import org.dom4j.io.SAXReader;
import org.dom4j.DocumentException;

import java.util.List;

public class XPathTextor {
   public void xPath(String xpathExp){
       String file = "F:\\idea workspace\\xmlText\\src\\plan.xml";
       //读取Xml文件
       SAXReader reader = new SAXReader();
       try {
           Document document = reader.read(file);
           //执行XPath方法
           List<Node> nodes = document.selectNodes(xpathExp);
           for (Node node : nodes){
               Element emp = (Element) node;
               System.out.println(emp.elementText("course-name"));
               System.out.println(emp.elementText("class-hour"));
               System.out.println(emp.elementText("exam-form"));
           }
       }catch (DocumentException e){
           e.printStackTrace();
       }
   }

   public static void main(String[] args) {
       XPathTextor xt = new XPathTextor();
       xt.xPath("/teaching-plan/course");
   }
}

结果

"C:\Program Files\Java\jdk-11.0.2\bin\java.exe" "-javaagent:F:\IntelliJ IDEA 2018.3.4\lib\idea_rt.jar=56894:F:\IntelliJ IDEA 2018.3.4\bin" -Dfile.encoding=UTF-8 -classpath "F:\idea workspace\xmlText\out\production\xmlText;F:\dom4j\dom4j-2.1.1.jar;F:\jaxen\jaxen-1.1.6.jar;F:\idea workspace\xmlText\lib\dom4j-2.1.1.jar;F:\idea workspace\xmlText\lib\jaxen-1.1.6.jar" com.imooc.plan.XPathTextor

进程已结束，退出代码 0