When the hopper. ImportOrLoad () is executed, the Demo project runs without problems, adding to my project error, the jar package is consistent.
This is the wrong reason.
Servlet.service() for servlet [dispatcher] in context with path [/OfflineMap] threw exception [Handler dispatch failed; nested exception is java.lang.NoClassDefFoundError: com/carrotsearch/hppc/IntLookupContainer] with root cause
java.lang.ClassNotFoundException: com.carrotsearch.hppc.IntLookupContainer
Sounds like a dependency issue. Do you use Maven?