java.lang.NoClassDefFoundError: org/slf4j/impl/StaticLoggerBinder 等的解决方法

java.lang.NoClassDefFoundError: org/slf4j/impl/StaticLoggerBinder
SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details
缺少slf4j-log4j12-1.5.6.jar包：
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java.lang.IllegalAccessError: tried to access field org.slf4j.impl.StaticLoggerBinder.SINGLETON from class org.slf4j.LoggerFactory
slf4j-log4j12-1.5.6.jar中没有org/slf4j/impl/StaticLoggerBinder这个类的存在，，所以再引入
slf4j-log4j12-1.5.2.jar
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 log4j:WARN No appenders could be found for logger (org.hibernate.cfg.Environment).
 log4j:WARN Please initialize the log4j system properly.
 Initial SessionFactory creation failed.org.hibernate.HibernateException: JDBC Driver class not found: oracle.jdbc.driver.OracleDriver
导入 classes12.jar