title: Apache POI NoClassDefFoundError while reading excel files
body: <p>I am attempting to run this code:</p>
  
  <pre><code>public class ExcelSimpleTest {
      public static void main(String[] args) throws  Exception {
            File f = new File("C:\\Users\\yaron\\Desktop\\Test.xlsx");
            FileInputStream fis = new FileInputStream(f);
  
            XSSFWorkbook wb=new XSSFWorkbook(fis);
            Sheet sheet=wb.getSheetAt(0);
            System.out.println(sheet.getRow(0).getCell(0).getStringCellValue());
      }
  
  }
  </code></pre>
  
  <p>And am getting this error:</p>
  
  <pre><code>    Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/collections4/ListValuedMap
      at src.ExcelSimpleTest.main(ExcelSimpleTest.java:22)
  Caused by: java.lang.ClassNotFoundException: org.apache.commons.collections4.ListValuedMap
      at java.net.URLClassLoader.findClass(Unknown Source)
      at java.lang.ClassLoader.loadClass(Unknown Source)
      at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
      at java.lang.ClassLoader.loadClass(Unknown Source)
      ... 1 more
  </code></pre>
  
  <p>I checked on the internet and copied over the Apache POI files and don't understand what my problem is. </p>