What is pointcut expression?
Pointcut is an expression language of spring AOP which is basically used to match the target methods to apply the advice. It has two parts ,one is the method signature comprising of method name and parameters. Other one is the pointcut expression which determines exactly which method we are applying the advice to.
What is a pointcut in AOP?
Pointcut is a set of one or more JoinPoint where an advice should be executed. You can specify Pointcuts using expressions or patterns as we will see in our AOP examples. In Spring, Pointcut helps to use specific JoinPoints to apply the advice.
What is the use of pointcut in Spring?
In Spring AOP, a join point always represents a method execution. A pointcut is a predicate that matches the join points and a pointcut expression language is a way of describing pointcuts programmatically.
What is aspect and pointcut?
It is the action taken by an aspect at a particular join-point. Joinpoint is a point of execution of the program, such as the execution of a method or the handling of an exception. In Spring AOP, a joinpoint always represents a method execution. Pointcut is a predicate or expression that matches join points.
What is the @RequestMapping annotation used for?
One of the most important annotations in spring is the @RequestMapping Annotation which is used to map HTTP requests to handler methods of MVC and REST controllers. In Spring MVC applications, the DispatcherServlet (Front Controller) is responsible for routing incoming HTTP requests to handler methods of controllers.
What is @aspect annotation in Spring boot?
Advertisements. @AspectJ refers to a style of declaring aspects as regular Java classes annotated with Java 5 annotations.
Is AspectJ thread safe?
AspectJ will execute your aspects on the current thread. That means, if you have a multi-threaded execution, your aspect will run on multiple threads as well. If your aspect works with shared state, you’ll need to make sure about accessing your shared state in a safe way.
What is @GetMapping and @PostMapping?
From the naming convention we can see that each annotation is meant to handle respective incoming request method type, i.e. @GetMapping is used to handle GET type of request method, @PostMapping is used to handle POST type of request method, etc.
What is the difference between PostMapping and RequestMapping?
Both do the same job. The difference is that @PostMapping is part of a predefined group of compound annotations that internally use @RequestMapping . These annotations act as shortcuts that serve to simplify the mapping of HTTP methods and to more concisely express the methods of manipulation.
What is EnableAsync?
EnableAsync is used for configuration and enable Spring’s asynchronous method execution capability, it should not be put on your Service or Component class, it should be put on your Configuration class like: @Configuration @EnableAsync public class AppConfig { }
What is @EnableAutoConfiguration?
The @EnableAutoConfiguration annotation enables Spring Boot to auto-configure the application context. Therefore, it automatically creates and registers beans based on both the included jar files in the classpath and the beans defined by us.
What is Apo in Spring boot?
AOP (Aspect-Oriented Programming) is a programming pattern that increases modularity by allowing the separation of the cross-cutting concern. These cross-cutting concerns are different from the main business logic. We can add additional behavior to existing code without modification of the code itself.
What is the use of @aspect annotation?
@After declares the after advice. It is applied after calling the actual method and before returning result. @AfterReturning declares the after returning advice. It is applied after calling the actual method and before returning result.
Are Singleton beans thread safe?
Singleton beans does not provide thread safety and now you know that instance variables usage may lead to unexpected result, you have 2 options to solve the same : Don’t use instance variables in multithreaded environment.
What is thisJoinPoint and how is it used?
Provides reflective access to both the state available at a join point and static information about it. This information is available from the body of advice using the special form thisJoinPoint. The primary use of this reflective information is for tracing and logging applications.
What is thisJoinPoint’s reflective information?
Provides reflective access to both the state available at a join point and static information about it. This information is available from the body of advice using the special form thisJoinPoint. The primary use of this reflective information is for tracing and logging applications.
What is an annotation and how do I use it?
Using an annotation gives us an easy mechanism for adding the trace logging output to new code without having to add logging statements directly. Let’s create the annotation: 3. Creating Our Aspect