Correction erreur prog ( tres urgent)

Bonsoir,
vous pouvez m'aidé svp : c tres urgent pour moi :
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exception in thread "main" java.lang.ExceptionInInitializerError at org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory(HibernatePersistence.java:119) at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:51) at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:33) at tests.Main.<clinit>(Main.java:19) Caused by: org.apache.commons.logging.LogConfigurationException: org.apache.commons.logging.LogConfigurationException: java.lang.NullPointerException (Caused by java.lang.NullPointerException) (Caused by org.apache.commons.logging.LogConfigurationException: java.lang.NullPointerException (Caused by java.lang.NullPointerException)) at org.apache.commons.logging.impl.LogFactoryImpl.newInstance(LogFactoryImpl.java:543) at org.apache.commons.logging.impl.LogFactoryImpl.getInstance(LogFactoryImpl.java:235) at org.apache.commons.logging.impl.LogFactoryImpl.getInstance(LogFactoryImpl.java:209) at org.apache.commons.logging.LogFactory.getLog(LogFactory.java:351) at org.hibernate.ejb.Ejb3Configuration.<clinit>(Ejb3Configuration.java:102) ... 4 more Caused by: org.apache.commons.logging.LogConfigurationException: java.lang.NullPointerException (Caused by java.lang.NullPointerException) at org.apache.commons.logging.impl.LogFactoryImpl.getLogConstructor(LogFactoryImpl.java:397) at org.apache.commons.logging.impl.LogFactoryImpl.newInstance(LogFactoryImpl.java:529) ... 8 more Caused by: java.lang.NullPointerException at org.apache.commons.logging.impl.LogFactoryImpl.getLogConstructor(LogFactoryImpl.java:374) ... 9 more Could not find the main class: tests.Main. Program will exit.
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merci