NoClassDefFoundErrorが：私はExcelシートからデータを取得しようとしていますWorkbookFactory.create（WorkbookFactory.java:266）

Question

が、これはコードです：私はそれを実行したときに

public static void main(String[] args) throws Exception { 
    File f = new File("C:\\Users\\Alex\\Documents\\Victoria.xlsx"); 
    Workbook wb = WorkbookFactory.create(f); 
    Sheet s = wb.getSheetAt(0); 
    Row r =s.getRow(0); 
    Cell c=r.getCell(0); 
    s.getLastRowNum(); 
    int rowcount = s.getLastRowNum(); 
    System.out.println("rows are"+rowcount); 
    System.out.println(c.getStringCellValue()); 
} 

これは私が取得していますエラーメッセージです：

WARNING: An illegal reflective access operation has occurred 
WARNING: Illegal reflective access by 
## Heading ## org.apache.poi.openxml4j.util.ZipSecureFile$1 (file:/C:/Users /Alex/Downloads/selenium-java-3.6.0/poi-3.17/poi-ooxml-3.17.jar) to field java.io.FilterInputStream.in 
WARNING: Please consider reporting this to the maintainers of org.apache.poi.openxml4j.util.ZipSecureFile$1 
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations 
WARNING: All illegal access operations will be denied in a future release 
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/collections4/ListValuedMap 
at org.apache.poi.ss.usermodel.WorkbookFactory.create(WorkbookFactory.java:266) 
at org.apache.poi.ss.usermodel.WorkbookFactory.create(WorkbookFactory.java:226) 
at org.apache.poi.ss.usermodel.WorkbookFactory.create(WorkbookFactory.java:205) 
at CreateSingle_ValueRet.main(CreateSingle_ValueRet.java:13) 
Caused by: java.lang.ClassNotFoundException: 
org.apache.commons.collections4.ListValuedMap 
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(Unknown Source) 
at java.base/java.lang.ClassLoader.loadClass(Unknown Source) 
... 4 more 

私はEclipse Oxigenを使用しています。

Answer 1

あなたのクラスパスにcommons-colletions4が見つかりません。それを追加すると、例外がなくなるはずです。