In this Spring AOP example, we will learn to use AspectJ @After annotation in Spring-based applications. After advice methods annotated with @After that will execute after a join point execution, no matter how the execution ended.
In this example, We will create a simple spring boot application, add logging aspect and then invoke aspect methods based on pointcuts information passed in a @After annotation.
AspectJ @After Annotation Usage
Below snippet shows usage of @After annotation:
package net.guides.springboot2.springaop.aspect;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.Aspect;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;
/**
* Aspect for logging execution.
*
* @author Ramesh Fadatare
*
*/
@Aspect
@Component
public class LoggingAspect {
private final Logger LOGGER = LoggerFactory.getLogger(this.getClass());
@After("execution(* net.guides.springboot2.springaop.service.EmployeeService.*(..))")
public void logAfterAllMethods(JoinPoint joinPoint) {
LOGGER.debug("****LoggingAspect.logAfterAllMethods() : " + joinPoint.getSignature().getName());
}
@After("execution(* net.guides.springboot2.springaop.service.EmployeeService.getEmployeeById(..))")
public void logAfterGetEmployee(JoinPoint joinPoint) {
LOGGER.debug("****LoggingAspect.logAfterGetEmployee() : " + joinPoint.getSignature().getName());
}
@After("execution(* net.guides.springboot2.springaop.service.EmployeeService.addEmployee(..))")
public void logAfterAddEmployee(JoinPoint joinPoint) {
LOGGER.debug("****LoggingAspect.logAfterCreateEmployee() : " + joinPoint.getSignature().getName());
}
@After("execution(* net.guides.springboot2.springaop.service.EmployeeService.deleteEmployee(..))")
public void logAfterDeleteEmployee(JoinPoint joinPoint) {
LOGGER.debug("****LoggingAspect.logAfterCreateEmployee() : " + joinPoint.getSignature().getName());
}
@After("execution(* net.guides.springboot2.springaop.service.EmployeeService.getAllEmployees(..))")
public void logAfterGetAllEmployees(JoinPoint joinPoint) {
LOGGER.debug("****LoggingAspect.logAfterCreateEmployee() : " + joinPoint.getSignature().getName());
}
}
Let's demonstrate the usage of @After annotation with a complete step by step example.
1. Creating a Spring Boot Application
There are many ways to create a Spring Boot application. You can refer below articles to create a Spring Boot application.
>> Create Spring Boot Project With Spring Initializer
>> Create Spring Boot Project in Spring Tool Suite [STS]
>> Create Spring Boot Project in Spring Tool Suite [STS]
Refer next step to create project packaging structure.
Maven Dependencies
<?xml version="1.0" encoding="UTF-8"?>
<project
xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>net.guides.springboot2</groupId>
<artifactId>springboot2-springaop-example</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>springboot2-springaop-example</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>3.0.4</version>
<relativePath />
<!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>17</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-aop</artifactId>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
Project Structure
Create an Aspect - LogginAspect.java
package net.guides.springboot2.springaop.aspect; import org.aspectj.lang.JoinPoint; import org.aspectj.lang.annotation.After; import org.aspectj.lang.annotation.Aspect; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.stereotype.Component; /** * Aspect for logging execution. * * @author Ramesh Fadatare * */ @Aspect @Component public class LoggingAspect { private final Logger LOGGER = LoggerFactory.getLogger(this.getClass()); @After("execution(* net.guides.springboot2.springaop.service.EmployeeService.*(..))") public void logAfterAllMethods(JoinPoint joinPoint) { LOGGER.debug("****LoggingAspect.logAfterAllMethods() : " + joinPoint.getSignature().getName()); } @After("execution(* net.guides.springboot2.springaop.service.EmployeeService.getEmployeeById(..))") public void logAfterGetEmployee(JoinPoint joinPoint) { LOGGER.debug("****LoggingAspect.logAfterGetEmployee() : " + joinPoint.getSignature().getName()); } @After("execution(* net.guides.springboot2.springaop.service.EmployeeService.addEmployee(..))") public void logAfterAddEmployee(JoinPoint joinPoint) { LOGGER.debug("****LoggingAspect.logAfterCreateEmployee() : " + joinPoint.getSignature().getName()); } @After("execution(* net.guides.springboot2.springaop.service.EmployeeService.deleteEmployee(..))") public void logAfterDeleteEmployee(JoinPoint joinPoint) { LOGGER.debug("****LoggingAspect.logAfterCreateEmployee() : " + joinPoint.getSignature().getName()); } @After("execution(* net.guides.springboot2.springaop.service.EmployeeService.getAllEmployees(..))") public void logAfterGetAllEmployees(JoinPoint joinPoint) { LOGGER.debug("****LoggingAspect.logAfterCreateEmployee() : " + joinPoint.getSignature().getName()); } }
Create a Java POJO - Employee.java
package net.guides.springboot2.springaop.model;
public class Employee {
private long id;
private String firstName;
private String lastName;
private String emailId;
public Employee() {
}
public Employee(long id, String firstName, String lastName, String emailId) {
this.id = id;
this.firstName = firstName;
this.lastName = lastName;
this.emailId = emailId;
}
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public String getEmailId() {
return emailId;
}
public void setEmailId(String emailId) {
this.emailId = emailId;
}
@Override
public String toString() {
return "Employee [id=" + id + ", firstName=" + firstName + ", lastName=" + lastName + ", emailId=" + emailId
+ "]";
}
}
Create service methods - EmployeeService.java
Let's create a few service methods for Employee on which aspects need to be executed.
package net.guides.springboot2.springaop.service;
import java.util.ArrayList;
import java.util.List;
import org.springframework.stereotype.Service;
import net.guides.springboot2.springaop.model.Employee;
/**
* Employee Service
*
* @author Ramesh
*
*/
@Service
public class EmployeeService {
private List < Employee > employees = new ArrayList < > ();
public List < Employee > getAllEmployees() {
System.out.println("Method getAllEmployees() called");
return employees;
}
public Employee getEmployeeById(Long employeeId) {
System.out.println("Method getEmployeeById() called");
for (Employee employee: employees) {
if (employee.getId() == Long.valueOf(employeeId)) {
return employee;
}
}
return null;
}
public void addEmployee(Employee employee) {
System.out.println("Method addEmployee() called");
employees.add(employee);
}
public void updateEmployee(Employee employeeDetails) {
System.out.println("Method updateEmployee() called");
for (Employee employee: employees) {
if (employee.getId() == Long.valueOf(employeeDetails.getId())) {
employees.remove(employee);
employees.add(employeeDetails);
}
}
}
public void deleteEmployee(Long employeeId) {
System.out.println("Method deleteEmployee() called");
for (Employee employee: employees) {
if (employee.getId() == Long.valueOf(employeeId)) {
employees.remove(employee);
}
}
}
}
Test Spring AspectJ Configuration and Execution
Now let’s test whether the above-configured aspects execute on given pointcut information using Spring boot Application:
package net.guides.springboot2.springaop;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ApplicationContext;
import net.guides.springboot2.springaop.model.Employee;
import net.guides.springboot2.springaop.service.EmployeeService;
@SpringBootApplication
public class Application {
public static void main(String[] args) {
ApplicationContext applicationContext = SpringApplication.run(Application.class, args);
EmployeeService employeeService = applicationContext.getBean(EmployeeService.class);
employeeService.addEmployee(new Employee(100 L, "ramesh", "fadatare", "ramesh@gmail.com"));
employeeService.getEmployeeById(100 L);
employeeService.getAllEmployees();
}
}
From the above diagram, it clears that aspect advice executed on relevant joinpoints.
To learn more about Spring AOP then check out the complete Spring AOP Tutorial.
Free Spring Boot Tutorial | Full In-depth Course | Learn Spring Boot in 10 Hours
Watch this course on YouTube at Spring Boot Tutorial | Fee 10 Hours Full Course