Question

I’m converting existing code to Spring 3 JDBC. I’ve put it into a class (SpringDB.Users) that implements ServletContextAware. In setServletContext(), the following code doesn’t work:

public void setServletContext(ServletContext sc)
{
    WebApplicationContext wac = WebApplicationContextUtils.getRequiredWebApplicationContext(sc);
    simpleJdbcTemplate = (SimpleJdbcTemplate) wac.getBean("simpleJdbcTemplate");
}

The reason is: exception is java.lang.IllegalStateException: No WebApplicationContext found: no ContextLoaderListener registered?

However I did register a ContextLoaderListener in web.xml:

<listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>

The applicationContext.xml has this:

<jee:jndi-lookup id="dataSource" jndi-name="java:comp/env/jdbc/mysql"/>
<bean id="simpleJdbcTemplate" class="org.springframework.jdbc.core.simple.SimpleJdbcTemplate">
    <constructor-arg>
        <ref bean="dataSource"/>
    </constructor-arg>
</bean>
<bean class="SpringDB.Users"/>

which results in getting the call to setServletContext(). The class SpringDB.Users is mostly static stuff. It is never instantiated by the java code.

Apparently, the call to WebApplicationContextUtils.getRequiredWebApplicationContext() is “too early”. Because what does work without any trouble is to get the WebApplicationContext at a later time, i.e. when database work really starts – so what I do is to call a private function getSimpleJdbcTemplate() instead of a private variable simpleJdbcTemplate:

static private SimpleJdbcTemplate getSimpleJdbcTemplate ()
{
    if (simpleJdbcTemplate == null)
    {
        WebApplicationContext wac = WebApplicationContextUtils.getRequiredWebApplicationContext(servletContext);
        simpleJdbcTemplate = (SimpleJdbcTemplate) wac.getBean("simpleJdbcTemplate");
    }
    return simpleJdbcTemplate;
}

Is there any solution so that the variable simpleJdbcTemplate can be initialized within setServletContext() ?

Am I missing something obvious, or just expecting too much?

Answer 1

Why do you need that in the first place?

If your class is a bean, then you can simply inject (with @Inject, @Autowired or xml) the jdbc template:

@Inject
private SimpleJdbcTemplate template;