hibernate: java.lang.noclassdeffounderror: com/mchange/v2/c3p0/datasources

Problem

If you are using c3p0 connection pool for hibernate, then you probably have
on the hibernate.cfg.xml file the following configuration:

<!-- c3p0 connection pool (use the built-in) -->
  <property name="connection.pool_size">c3p0</property>
  <property name="c3p0.min_size">5</property>
  <property name="c3p0.max_size">20</property>
  <property name="c3p0.timeout">1800</property>
  <property name="c3p0.max_statements">50</property>


When you run the application, it throws an exception like below:



21:03:25,016  INFO C3P0ConnectionProvider:82 - Connection properties: {user=root, password=****}
21:03:25,016  INFO C3P0ConnectionProvider:85 - autocommit mode: false
21:03:25,023  WARN C3P0ConnectionProvider:210 - Both hibernate-style property 'hibernate.c3p0.max_size' and c3p0-style property 'c3p0.max_size' have
been set in hibernate.properties.
Hibernate-style property 'hibernate.c3p0.max_size' will be used and c3p0-style property 'c3p0.max_size' will be ignored!
21:03:25,023  WARN C3P0ConnectionProvider:210 - Both hibernate-style property 'hibernate.c3p0.min_size' and c3p0-style property 'c3p0.min_size' have
been set in hibernate.properties.
Hibernate-style property 'hibernate.c3p0.min_size' will be used and c3p0-style property 'c3p0.min_size' will be ignored!
21:03:25,024  WARN C3P0ConnectionProvider:210 - Both hibernate-style property 'hibernate.c3p0.timeout' and c3p0-style property 'c3p0.timeout' have
been set in hibernate.properties.
Hibernate-style property 'hibernate.c3p0.timeout' will be used and c3p0-style property 'c3p0.timeout' will be ignored!
21:03:25,024  WARN C3P0ConnectionProvider:210 - Both hibernate-style property 'hibernate.c3p0.max_statements' and c3p0-style property
'c3p0.max_statements' have been set in hibernate.properties.Hibernate-style property 'hibernate.c3p0.max_statements' will be used and c3p0-style property 'c3p0.max_statements' will be ignored!
Initial SessionFactory creation failed.java.lang.NoClassDefFoundError: com/mchange/v2/c3p0/DataSources
Exception in thread "main" java.lang.ExceptionInInitializerError
  at ipg.model.persistence.hbn.HbnDaoFactory.<clinit>(HbnDaoFactory.java:43)
  at test.db.AdminVO_test.showList(AdminVO_test.java:120)
  at test.db.AdminVO_test.main(AdminVO_test.java:46)
Caused by: java.lang.NoClassDefFoundError: com/mchange/v2/c3p0/DataSources
  at org.hibernate.connection.C3P0ConnectionProvider.configure(C3P0ConnectionProvider.java:154)
  at org.hibernate.connection.ConnectionProviderFactory.newConnectionProvider(ConnectionProviderFactory.java:124)
  at org.hibernate.connection.ConnectionProviderFactory.newConnectionProvider(ConnectionProviderFactory.java:56)
  at org.hibernate.cfg.SettingsFactory.createConnectionProvider(SettingsFactory.java:414)
  at org.hibernate.cfg.SettingsFactory.buildSettings(SettingsFactory.java:62)
  at org.hibernate.cfg.Configuration.buildSettings(Configuration.java:2073)
  at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1298)
  at ipg.model.persistence.hbn.HbnDaoFactory.<clinit>(HbnDaoFactory.java:39)
  ... 2 more
Caused by: java.lang.ClassNotFoundException: com.mchange.v2.c3p0.DataSources
  at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
  at java.security.AccessController.doPrivileged(Native Method)
  at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
  at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
  at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
  at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
  ... 10 more

Solution

Missing  the c3p0 jar files on the project's build path.
Download the jar file, for instance:
c3p0-0.9.1.2.jar