SLF4J: This version of SLF4J requires log4j version 1.2.12 or later. See also http://www.slf4j.org/codes.html#log4j_version
log4j:WARN No appenders could be found for logger (org.hibernate.cfg.Environment).
log4j:WARN Please initialize the log4j system properly.
Exception in thread "main" org.hibernate.PropertyNotFoundException: Could not find a getter for Room_ID in class com.entity.room
at org.hibernate.property.BasicPropertyAccessor.createGetter(BasicPropertyAccessor.java:306)
at org.hibernate.property.BasicPropertyAccessor.getGetter(BasicPropertyAccessor.java:299)
at org.hibernate.tuple.PropertyFactory.getGetter(PropertyFactory.java:191)
at org.hibernate.tuple.PropertyFactory.buildIdentifierProperty(PropertyFactory.java:67)
at org.hibernate.tuple.entity.EntityMetamodel.<init>(EntityMetamodel.java:136)
at org.hibernate.persister.entity.AbstractEntityPersister.<init>(AbstractEntityPersister.java:456)
at org.hibernate.persister.entity.SingleTableEntityPersister.<init>(SingleTableEntityPersister.java:131)
at org.hibernate.persister.PersisterFactory.createClassPersister(PersisterFactory.java:84)
at org.hibernate.impl.SessionFactoryImpl.<init>(SessionFactoryImpl.java:267)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1341)
at com.test.ceshi.main(ceshi.java:18)
------解决方案--------------------
命名可能不对，应该是：
public int getRoomId() {
return room_id;
}
------解决方案--------------------
一般来说，值对象映射时，下划线都会忽略掉。
具体可以查查你所使用数据访问组件的命名规则。