why Error creating bean with name 'edao' and could not load JDBC driver

By: nirmal*** On: Mon Jun 08 20:39:21 IST 2015     0 0 0	0
INFO: Loading XML bean definitions from class path resource [applicationContext.xml] Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'edao' defined in class path resource [applicationContext.xml]: Cannot resolve reference to bean 'jdbcTemplate' while setting bean property 'jdbcTemplate'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'jdbcTemplate' defined in class path resource [applicationContext.xml]: Cannot resolve reference to bean 'dtsr' while setting bean property 'dataSource'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'dtsr' defined in class path resource [applicationContext.xml]: Error setting property values; nested exception is org.springframework.beans.PropertyBatchUpdateException; nested PropertyAccessExceptions (1) are: PropertyAccessException 1: org.springframework.beans.MethodInvocationException: Property 'driverClassName' threw exception; nested exception is java.lang.IllegalStateException: Could not load JDBC driver class [org.postgresql.Driver]	0