You could implement the InitializingBean interface which has one method (afterPropertiesSet()) which is called after all properties are set on the bean. The problem with this is that it ties your class to the Spring API.
Another alternative is to create a method which can be declared as the init-method in the xml declaration of your bean (if you are using xml to declare your bean)
Code:
<bean id="exampleInitBean" class="examples.ExampleBean" init-method="init"/>
If your using annotations then use the @PostConstruct annotation for your init method.
HTH