We are familiar with the well known whitelabel error in Spring Boot.
It appears when the application will not find the resource the user is
looking for or any internal application error. This application will
demonstrate on how to handle these errors. Spring Boot 1.5.3 has made it
easy to handle such error by providing the easy implementation on the
user side.
First, let us create a simple Spring Boot application. You can use any IDE or go to start.spring.io and create your project. After creating your project, run it as Java application (In eclipse, right click the project -> Run as -> Java Application) or Spring Boot application if you have STS installed. You can download the source code from here. Now, try to access localhost:8080 and you'll see the first whitelabel error because spring boot application is looking for index.html but we haven't defined anything in our application. So, you'll see the error like this.
Now, let us create index.html inside
and write something like this.
Let's create a PageController and define the route to index.html, this way we'll not see the whitelabel error when we try to access localhost:8080
Write some messages inside 404.html page that is easy for the user to understand or your own messages
To handle this error, create 5xx.html file inside the previous /error folder. Here, 5xx means 500, 501, 503, etc.
Write meaningful message inside this 5xx.html page
We've created our own custom error handling in Spring Boot. You can download the source code from here.
First, let us create a simple Spring Boot application. You can use any IDE or go to start.spring.io and create your project. After creating your project, run it as Java application (In eclipse, right click the project -> Run as -> Java Application) or Spring Boot application if you have STS installed. You can download the source code from here. Now, try to access localhost:8080 and you'll see the first whitelabel error because spring boot application is looking for index.html but we haven't defined anything in our application. So, you'll see the error like this.
Now, let us create index.html inside
src/main/resources/templates folder like in the below pictureand write something like this.
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8"/>
<title>Spring Boot Custom error handling</title>
</head>
<body>
<p>Demo application for custom error handling in Spring Boot</p>
</body>
</html>Let's create a PageController and define the route to index.html, this way we'll not see the whitelabel error when we try to access localhost:8080
package pro.budthapa.controller;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
@Controller
public class PageController {
private static final String INDEX= "index";
@GetMapping("/")
public String index(){
return INDEX;
}
}
Handle 404 error in Spring Boot
But if you want to access other resources likelocalhost:8080/something
then you'll get the whitelabel error with status code 404. To handle
this, let us create a error folder inside src/main/resources/templates/.
Inside this folder create a file named 404.htmlWrite some messages inside 404.html page that is easy for the user to understand or your own messages
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8"/>
<title>404 Not found</title>
</head>
<body>
<p>404 Error. Oops! The resource you are looking is not found.</p>
</body>
</html>Let us handle the 500 Internal server error in Spring Boot
First, let us create method named about inside the PageController and point it to about.html page.package pro.budthapa.controller;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
@Controller
public class PageController {
private final String INDEX= "index";
private final String ABOUT= "about";
@GetMapping("/")
public String index(){
return INDEX;
}
@GetMapping("/about")
public String about(){
return ABOUT;
}
}
To handle this error, create 5xx.html file inside the previous /error folder. Here, 5xx means 500, 501, 503, etc.
Write meaningful message inside this 5xx.html page
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8"/>
<title>5xx error handling</title>
</head>
<body>
<p>Handling error with status code 5xx. eg: 500, 503 etc. </p>
</body>
</html>We've created our own custom error handling in Spring Boot. You can download the source code from here.
Is there a way to do this while also including logging on a controller as well as a common error page for all errors not caught?
ReplyDeleteYes you can do it. Use @ControllerAdvice annotation. Check here
ReplyDelete