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This tutorial shows how to create Interceptor Chain.
Order in which they are added to configuration defines order in which their Methods are executed
● their prehandle() Methods are executed during HTTP Request in that order
● their posthandle() Methods are executed during HTTP Response in reverse order
● their afterCompletion() Methods are executed during HTTP Response in reverse order
Application Schema [Results]
Spring Boot Starters
GROUP
DEPENDENCY
DESCRIPTION
Web
Spring Web
Enables: Controller Annotations, Tomcat Server
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Create Project: springboot_filter_create (add Spring Boot Starters from the table)
Create Package: controllers (inside main package)
– Create Class: MyController.java (inside controllers package)
Create Package: interceptors (inside main package)
– Create Class: MyInterceptor1.java (inside controllers package)
– Create Class: MyInterceptor2.java (inside controllers package)
– Create Class: InterceptorConfig.java (inside controllers package)
MyController.java
package com.ivoronline.springboot_interceptor.controllers;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.ResponseBody;
@Controller
public class MyController {
@ResponseBody
@RequestMapping("/Hello")
public String hello() {
System.out.println("Controller:");
return "Hello from Controller";
}
}
MyInterceptor1
MyController
Request
Response
MyInterceptor2
Request
Response
Request
Response
InterceptorConfig
MyInterceptor1.java
package com.ivoronline.springboot_interceptor_chain.interceptors;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@Component
public class MyInterceptor1 implements HandlerInterceptor {
//====================================================================
// PRE HANDLE
//====================================================================
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) {
System.out.print("MyInterceptor1: preHandle() ");
return true;
}
//====================================================================
// POST HANDLE
//====================================================================
@Override
public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
ModelAndView modelAndView) {
System.out.print("MyInterceptor1: postHandle() ");
}
//====================================================================
// AFTER COMPLETION
//====================================================================
@Override
public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler,
Exception exception) {
System.out.print("MyInterceptor1: afterCompletion() ");
}
}
MyInterceptor2.java
package com.ivoronline.springboot_interceptor_chain.interceptors;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@Component
public class MyInterceptor2 implements HandlerInterceptor {
//====================================================================
// PRE HANDLE
//====================================================================
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) {
System.out.print("MyInterceptor2: preHandle() ");
return true;
}
//====================================================================
// POST HANDLE
//====================================================================
@Override
public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
ModelAndView modelAndView) {
System.out.print("MyInterceptor2: postHandle() ");
}
//====================================================================
// AFTER COMPLETION
//====================================================================
@Override
public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler,
Exception exception) {
System.out.print("MyInterceptor2: afterCompletion() ");
}
}
InterceptorConfig.java
package com.ivoronline.springboot_interceptor_chain.interceptors;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport;
@Component
public class InterceptorConfig extends WebMvcConfigurationSupport {
@Autowired MyInterceptor1 myInterceptor1;
@Autowired MyInterceptor2 myInterceptor2;
@Override
public void addInterceptors(InterceptorRegistry registry) {
//ORDER IN WHICH THEY ARE ADDED DEFINES ORDER IN WHICH THEIR METHODS ARE EXECUTED
//- prehandle() Methods are executed during HTTP Request in that order
//- posthandle() Methods are executed during HTTP Response in reverse order
//- afterCompletion() Methods are executed during HTTP Response in reverse order
registry.addInterceptor(myInterceptor1);
registry.addInterceptor(myInterceptor2);
}
}