NoClassDefFoundError: org/openxmlformats/schemas/spreadsheetml/x2006/main/ExternalLinkDocument

Error

Exception in thread "main" java.lang.NoClassDefFoundError: org/openxmlformats/schemas/spreadsheetml/x2006/main/ExternalLinkDocument
	at org.apache.poi.xssf.model.ExternalLinksTable.readFrom(ExternalLinksTable.java:72)
	at org.apache.poi.xssf.model.ExternalLinksTable.<init>(ExternalLinksTable.java:66)
	at org.apache.poi.ooxml.POIXMLFactory.createDocumentPart(POIXMLFactory.java:61)
	at org.apache.poi.ooxml.POIXMLDocumentPart.read(POIXMLDocumentPart.java:661)
	at org.apache.poi.ooxml.POIXMLDocument.load(POIXMLDocument.java:165)
	at org.apache.poi.xssf.usermodel.XSSFWorkbook.<init>(XSSFWorkbook.java:260)
	at org.apache.poi.xssf.usermodel.XSSFWorkbook.<init>(XSSFWorkbook.java:290)
	at org.apache.poi.xssf.usermodel.XSSFWorkbook.<init>(XSSFWorkbook.java:286)
	at hello.Lautturi.main(Lautturi.java:101)
Caused by: java.lang.ClassNotFoundException: org.openxmlformats.schemas.spreadsheetml.x2006.main.ExternalLinkDocument
	at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:641)
	at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:188)
	at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
	... 9 more

Solution

Download POI Jar from
https://poi.apache.org/download.html

add poi-ooxml-full-5.2.3.jar to the classpath of your project.