Is there a way to check if a bean is defined in spring context?

Question

I am trying to create an object factory, which will first check if a bean has been specifically define in spring context. If such a bean is not found, It would check for other ways to create the instance.

I have implemented it using the following code

try {
        component = (PageComponent) appContext.getBean(w.getName());
    } catch (org.springframework.beans.factory.NoSuchBeanDefinitionException e) {
            component = loadFromDB(w, page);
    }

It is working, however an exception object is created whenever the bean is not available in Spring Context.

Is there a way to avoid this? or in other words Is there a way to check if a bean is defined in spring context?

Answer 1

Try this:

if(appContext.containsBeanDefinition(w.getName()))
    ; // Get the bean

Answer 2

beanFactory.containsBean(w.getName()) will return a boolean value depending on if there's already a bean registered by this name. Take a look at here.

Do something like this

if (!((BeanFactory) applicationContext).containsBean(w.getName())) {
     component = loadFromDB(w, page);
}

Answer 3

You can also use ApplicationContextRunner

Suppose I have a bean that conditional on some config-prop.

class IsExistBeanTest {

  private final ApplicationContextRunner contextRunner = new ApplicationContextRunner()
      .withUserConfiguration(SomeConfig.class)                          

  @Test
  void TestIfBeanIsThereWhenPropsExist() {
    contextRunner
        .withPropertyValues("some-left-service=false")
        .run(context -> assertAll(
            () -> assertThat(context).hasSingleBean(SomeBean.class),
            () -> assertThat(context).doesNotHaveBean(SomeOtherBean.class)));
            () -> assertThat(context).hasBean(SomeBean2.class)));
           //() -> more test case
  }