why i am getting NullPointerException in sessionfactory?

Exception in thread "main" java.lang.NullPointerException at org.hibernate.internal.util.StringHelper.unqualify(StringHelper.java:295) at org.hibernate.boot.model.source.internal.hbm.AbstractEntitySourceImpl.extractEntityNamingSource(AbstractEntitySourceImpl.java:119) at org.hibernate.boot.model.source.internal.hbm.AbstractEntitySourceImpl.(AbstractEntitySourceImpl.java:82) at org.hibernate.boot.model.source.internal.hbm.RootEntitySourceImpl.(RootEntitySourceImpl.java:25) at org.hibernate.boot.model.source.internal.hbm.EntityHierarchyBuilder.indexMappingDocument(EntityHierarchyBuilder.java:96) at org.hibernate.boot.model.source.internal.hbm.HbmMetadataSourceProcessorImpl.(HbmMetadataSourceProcessorImpl.java:63) at org.hibernate.boot.model.source.internal.hbm.HbmMetadataSourceProcessorImpl.(HbmMetadataSourceProcessorImpl.java:40) at org.hibernate.boot.model.process.spi.MetadataBuildingProcess$1.(MetadataBuildingProcess.java:161) at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:158) at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.build(MetadataBuildingProcess.java:86) at org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:479) at org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:85) at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:709) at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:746) at org.bankmanagement.dao.impl.AccountDAOImpl.(AccountDAOImpl.java:15) at org.bankmanagement.service.impl.AccountServiceImpl.(AccountServiceImpl.java:10) at org.bankmanagement.controller.AccountController.(AccountController.java:12) at org.bankmanagement.MainApplication.main(MainApplication.java:16)