Spring @ControllerAdvice Annotation Example
In this section we will learn about @ControllerAdvice Annotation.
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The @ControllerAdvice is a specialization of the @Component annotation which sanctions to handle exceptions across the whole application in one global handling component. It can be viewed as an interceptor of exceptions thrown by methods annotated with @RequestMapping and kindred.
It declares @ExceptionHandler, @InitBinder, or @ModelAttribute methods to be shared across multiple @Controller classes.
ResponseEntityExceptionHandler is a convenient base class for @ControllerAdvice classes that wish to provide centralized exception handling across all @RequestMapping methods through @ExceptionHandler methods. It provides an methods for handling internal Spring MVC exceptions. It returns a ResponseEntity in contrast to DefaultHandlerExceptionResolver which returns a ModelAndView.
The following example creates a Spring Boot web application which uses @ControllerAdvice.
Project Directory
Pom.xml
<?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
https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>3.0.1</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.knf.dev.demo</groupId>
<artifactId>spring-controlleradvice-example</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>spring-controlleradvice-example</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>17</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>com.h2database</groupId>
<artifactId>h2</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
Create User Entity - User.java
package com.knf.dev.demo.entity;
import jakarta.persistence.*;
@Entity
@Table(name = "userTable")
public class User {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private long id;
@Column(name = "first_name")
private String firstName;
@Column(name = "last_name")
private String lastName;
@Column(name = "email_id")
private String emailId;
public User() {
}
public User(String firstName, String lastName, String emailId) {
super();
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;
}
}
UserRepository.java
package com.knf.dev.demo.repository;
import com.knf.dev.demo.entity.User;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;
@Repository
public interface UserRepository extends JpaRepository<User, Long> {
}
CustomErrorResponse.java
package com.knf.dev.demo.exception;
import com.fasterxml.jackson.annotation.JsonFormat;
import java.time.LocalDateTime;
public class CustomErrorResponse {
@JsonFormat(shape = JsonFormat.Shape.STRING,
pattern = "yyyy-MM-dd hh:mm:ss")
private LocalDateTime timestamp;
private int status;
private String error;
public LocalDateTime getTimestamp() {
return timestamp;
}
public void setTimestamp(LocalDateTime timestamp) {
this.timestamp = timestamp;
}
public int getStatus() {
return status;
}
public void setStatus(int status) {
this.status = status;
}
public String getError() {
return error;
}
public void setError(String error) {
this.error = error;
}
}
UserNotFoundException.java
package com.knf.dev.demo.exception;
import org.springframework.http.HttpStatus;
import org.springframework.web.bind.annotation.ResponseStatus;
public class UserNotFoundException extends RuntimeException{
private static final long serialVersionUID = 1L;
public UserNotFoundException(String message) {
super(message);
}
}
GlobalExceptionHandler.java
package com.knf.dev.demo.exception;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.context.request.WebRequest;
import java.time.LocalDateTime;
@ControllerAdvice
public class GlobalExceptionHandler {
@ExceptionHandler(UserNotFoundException.class)
public ResponseEntity<CustomErrorResponse> userNotFound
(Exception ex, WebRequest request) {
CustomErrorResponse errors = new CustomErrorResponse();
errors.setTimestamp(LocalDateTime.now());
errors.setError(ex.getMessage());
errors.setStatus(HttpStatus.NOT_FOUND.value());
return new ResponseEntity<>(errors, HttpStatus.NOT_FOUND);
}
}
UserController.java
package com.knf.dev.demo.controller;
import com.knf.dev.demo.entity.User;
import com.knf.dev.demo.exception.UserNotFoundException;
import com.knf.dev.demo.repository.UserRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;
@RestController
@RequestMapping("/api/v1")
public class UserController {
@Autowired
private UserRepository userRepository;
// create user rest API
@PostMapping("/users")
public User createUser(@RequestBody User user) {
return userRepository.save(user);
}
// get user by id rest api
@GetMapping("/users/{id}")
public ResponseEntity<User> getUserById(@PathVariable Long id) {
User user = userRepository.findById(id)
.orElseThrow(() -> new UserNotFoundException
("User does not exist with id :" + id));
return ResponseEntity.ok(user);
}
}
Run Application - Application.java
Application is the entry point that sets up the Spring Boot application. The @SpringBootApplication annotation enables auto-configuration and component scanning.
Let's run this Spring boot application from either IntelliJ IDEA IDE by right click - Run 'Application.main()'
Or you can use the below maven command to run:
mvn spring-boot:runCreate User
Try to get User by id 2, you will get "User does not exist with id :2" message.
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