A common Hibernate’s error, this is caused by the missing dependency library – Apache Common Collection.

Initial SessionFactory creation failed.java.lang.NoClassDefFoundError: org/apache/commons/collections/SequencedHashMap
Exception in thread "main" java.lang.ExceptionInInitializerError
	at com.mkyong.persistence.HibernateUtil.buildSessionFactory(HibernateUtil.java:18)
	at com.mkyong.persistence.HibernateUtil.<clinit>(HibernateUtil.java:8)
	at com.mkyong.common.App.main(App.java:17)
Caused by: java.lang.NoClassDefFoundError: org/apache/commons/collections/SequencedHashMap
	at org.hibernate.mapping.Table.<init>(Table.java:33)
	at org.hibernate.cfg.Mappings.addTable(Mappings.java:165)
	at org.hibernate.cfg.HbmBinder.bindRootPersistentClassCommonValues(HbmBinder.java:290)
	at org.hibernate.cfg.HbmBinder.bindRootClass(HbmBinder.java:273)
	at org.hibernate.cfg.HbmBinder.bindRoot(HbmBinder.java:144)
	at org.hibernate.cfg.Configuration.add(Configuration.java:669)
	at org.hibernate.cfg.Configuration.addInputStream(Configuration.java:504)
	at org.hibernate.cfg.Configuration.addResource(Configuration.java:566)
	at org.hibernate.cfg.Configuration.parseMappingElement(Configuration.java:1587)
	at org.hibernate.cfg.Configuration.parseSessionFactory(Configuration.java:1555)
	at org.hibernate.cfg.Configuration.doConfigure(Configuration.java:1534)
	at org.hibernate.cfg.Configuration.doConfigure(Configuration.java:1508)
	at org.hibernate.cfg.Configuration.configure(Configuration.java:1428)
	at org.hibernate.cfg.Configuration.configure(Configuration.java:1414)
	at com.mkyong.persistence.HibernateUtil.buildSessionFactory(HibernateUtil.java:13)
	... 2 more
Caused by: java.lang.ClassNotFoundException: org.apache.commons.collections.SequencedHashMap
	at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:252)
	at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320)
	... 17 more

Solution

You can download the library here – http://commons.apache.org/collections/

Or

Add the dependency in Maven’s pom.xml

      <dependency>
		<groupId>commons-collections</groupId>
		<artifactId>commons-collections</artifactId>
		<version>3.2.1</version>
      </dependency>
This article was posted in Hibernate category.