Package io.microsphere.spring.context.event

Interface ApplicationEventInterceptor

All Superinterfaces:

org.springframework.core.Ordered

public interface ApplicationEventInterceptor
extends org.springframework.core.Ordered

An interface used to intercept application events allowing for pre-processing, post-processing, or even prevention of event propagation through the interceptor chain.

Interceptors can be used to implement cross-cutting concerns such as logging, security checks, or performance monitoring around the application event handling process.

Example Usage

 public class LoggingInterceptor implements ApplicationEventInterceptor {
     @Override
     public void intercept(ApplicationEvent event, ResolvableType eventType, ApplicationEventInterceptorChain chain) {
         System.out.println("Before handling event: " + event);
         chain.intercept(event, eventType); // Continue the interceptor chain
         System.out.println("After handling event: " + event);
     }
 }
 

Interceptors are typically ordered using the Ordered interface or @Order annotation to control the order in which they are applied.

Since:

1.0.0

Author:

Mercy

See Also:

• ApplicationEvent
• ApplicationEventInterceptorChain
• Ordered

Field Summary

Fields inherited from interface org.springframework.core.Ordered

HIGHEST_PRECEDENCE, LOWEST_PRECEDENCE

Method Summary

Modifier and Type	Method	Description
default int	getOrder()
void	intercept(org.springframework.context.ApplicationEvent event, org.springframework.core.ResolvableType eventType, ApplicationEventInterceptorChain chain)	Intercept the specified ApplicationEvent with its resolved type, allowing custom pre-processing, post-processing, or short-circuiting the event propagation by not invoking the next interceptor in the chain.

Method Details

intercept

void intercept(org.springframework.context.ApplicationEvent event,
 org.springframework.core.ResolvableType eventType,
 ApplicationEventInterceptorChain chain)

Intercept the specified ApplicationEvent with its resolved type, allowing custom pre-processing, post-processing, or short-circuiting the event propagation by not invoking the next interceptor in the chain.

Example Usage

Implementing a simple logging interceptor:

 public class SampleInterceptor implements ApplicationEventInterceptor {
     public void intercept(ApplicationEvent event, ResolvableType eventType, ApplicationEventInterceptorChain chain) {
         System.out.println("Intercepting event: " + event);
         // Proceed to the next interceptor in the chain
         chain.intercept(event, eventType);
         System.out.println("Finished handling event: " + event);
     }
 }
 

Short-circuiting: To prevent further processing of an event, simply skip calling ApplicationEventInterceptorChain.intercept(ApplicationEvent, ResolvableType):

 public class SilentEventInterceptor implements ApplicationEventInterceptor {
     public void intercept(ApplicationEvent event, ResolvableType eventType, ApplicationEventInterceptorChain chain) {
         // Skip calling chain.proceed() to prevent event propagation
         System.out.println("Event blocked: " + event);
     }
 }
 

Parameters:

event - the event being intercepted; never null

eventType - the resolved type of the event, useful for filtering or conditional logic

chain - the interceptor chain to continue processing if desired

getOrder

default int getOrder()

Specified by:

getOrder in interface org.springframework.core.Ordered