[FIXED] Is component defined with request scope lazy loaded?

Issue

A component is defined with request scope, it provides data based on HttpServletRequest object as shown below.

@Component
@RequestScope
@Getter
public class RequestDataHolder {
  private final Object data;

  public RequestDataHolder(HttpServletRequest request) {
    data = //costly operations; 
  }
}

When is the component instantiated? I would like to prevent the costly operations when data is not needed, so was thinking about annotating the component with @Lazy, but if it is instantiated when accessed by default, the annotation would be redundant.

Solution

According to docs.spring.io:

@RequestScope is a composed annotation that acts as a shortcut for @Scope("request") with the default proxyMode() set to TARGET_CLASS.

This means that the request scoped bean is provided as a CGLIB proxy by default when injected into a singleton bean. The proxy either instantiate the bean or reuse the existing one.

The bean is instantiated when its proxy's method is invoked, which produces the same effect as the @Lazy annotation.

Answered By - birca123
Answer Checked By - David Goodson (JavaFixing Volunteer)