title: "error: cannot find symbol" using Apache POI
body: <p>This is my code:</p>
  
  <pre><code>import java.io.FileInputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.util.*;
  
  import org.apache.poi.xssf.usermodel.XSSFCell;
  import org.apache.poi.xssf.usermodel.XSSFRow;
  import org.apache.poi.xssf.usermodel.XSSFSheet;
  import org.apache.poi.xssf.usermodel.XSSFWorkbook;
  
  
  public class Reader {
  
      public static void read_excel() {
  
          File excel =  new File ("C:\\Users\\Username\\Desktop\\java-Tools\\data.xlsx");
          FileInputStream fis = new FileInputStream(excel);
          XSSFWorkbook wb = new XSSFWorkbook(fis);
  }
  </code></pre>
  
  <p>This results in the following error message: </p>
  
  <pre><code>error: cannot find symbol 
  File excel =  new File ("C:\\Users\\Username\\Desktop\\java-Tools\\data.xlsx");
  symbol: class File
  location: class reader
  </code></pre>
  
  <p>I have set the CLASSPATH for the jar files of the Apache POI library. Here is the content of the CLASSPATH varibale:</p>
  
  <pre><code>.;C:\Users\Username\Desktop\Code\Classes;C:\poi-3.12\poi-3.12-20150511.jar;C:\poi-3.12\poi-ooxml-3.12-20150511.jar;C:\poi-3.12\poi-ooxml-schemas-3.12-20150511.jar;C:\poi-3.12\ooxml-lib\xmlbeans-2.6.0.jar;C:\poi-3.12\lib\commons-codec-1.9.jar;C:\poi-3.12\lib\commons-logging-1.1.3.jar;C:\poi-3.12\lib\junit-4.12.jar; C:\poi-3.12\lib\log4j-1.2.17.jar;C:\poi-3.12\poi-examples-3.12-20150511.jar;C:\poi-3.12\poi-excelant-3.12-20150511.jar;C:\poi-3.12\poi-scratchpad-3.12-20150511.jar
  </code></pre>
  
  <p>I don't understand why the programme does not compile !</p>