Pointcut expressions in Spring Boot - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a pointcut expression in Spring AOP?

A pointcut expression defines where advice should be applied by matching method executions or join points in the code.

beginner

Explain the use of the execution() designator in pointcut expressions.

The execution() designator matches method executions based on method signature patterns like return type, method name, and parameters.

intermediate

What does the pointcut expression execution(* com.example.service.*.*(..)) mean?

It matches the execution of any method with any return type, in any class inside the <code>com.example.service</code> package, with any number of arguments.

intermediate

How can you combine multiple pointcut expressions?

You can combine pointcuts using logical operators like && (and), || (or), and ! (not) to create complex matching rules.

beginner

What is the role of wildcards (*) and double dots (..) in pointcut expressions?

The wildcard * matches any single part like a method name or type, while .. matches any number of parameters or sub-packages.

Which pointcut designator matches method executions by signature?

A this()

B within()

C execution()

D args()

The execution() designator matches method executions based on method signatures.

What does the wildcard * represent in a pointcut expression?

A No match

B Any number of parameters

C Any sub-package

D Any single part like a method name or type

The * wildcard matches any single part such as a method name or type.

How do you exclude a pointcut from another using logical operators?

A !

B ||

C &&

D ==

The ! operator negates a pointcut, effectively excluding it.

Which expression matches all methods in a package and its sub-packages?

A execution(* com.example..*.*(..))

B execution(* com.example.*.*(..))

C within(com.example.*)

D args(com.example..*)

The double dot .. matches sub-packages, so com.example..* includes all sub-packages.

What does execution(public * *(..)) match?

A Any method with no parameters

B Any public method with any return type and any parameters

C Only private methods

D Only methods returning void

It matches any public method regardless of return type or parameters.

Describe how pointcut expressions help in applying advice in Spring AOP.

Think about how you tell Spring where to run extra code.

Explain the difference between the wildcards * and .. in pointcut expressions.

One is for single parts, the other for multiple parts.