1. Introduction
In this tutorial, we'll look at how we get and resolve Circular View Path errors in a Spring MVC application.
2. Dependencies
To demonstrate this, let's create a simple Spring Boot web project. First, we need to add the Spring Boot web starter dependency in our Maven project file:
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
3. Reproducing the Problem
Then, let's create a simple Spring Boot application with one Controller that resolves to one path:
@Controller
public class CircularViewPathController {
@GetMapping("/path")
public String path() {
return "path";
}
}
The return value is the view name that will produce response data. In our case, the return value is path which is associated with the path.html template:
<html>
<head>
<title>path.html</title>
</head>
<body>
<p>path.html</p>
</body>
</html>
After we start the server, we can reproduce the error by making a GET request to http://localhost:8080/path. The result will be the Circular View Path error:
{"timestamp":"2020-05-22T11:47:42.173+0000","status":500,"error":"Internal Server Error",
"message":"Circular view path [path]: would dispatch back to the current handler URL [/path]
again. Check your ViewResolver setup! (Hint: This may be the result of an unspecified view,
due to default view name generation.)","path":"/path"}
4. Solutions
By default, the Spring MVC framework applies the InternalResourceView class as the view resolver. As a result, if the @GetMapping value is the same as the view, the request will fail with the Circular View path error.
One possible solution would be to rename the view and change the return value in the controller method.
@Controller
public class CircularViewPathController {
@GetMapping("/path")
public String path() {
return "path2";
}
}
If we don't want to rename the view and change the return value in the controller method, then another solution is to choose another view processor for the project.
For the most common cases, we can choose the Thymeleaf Java template engine. Let's add the spring-boot-starter-thymeleaf dependency to the project:
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
After rebuilding the project we can run it again, and the request is successful. In this case, Thymeleaf replaces the InternalResourceView class.
5. Conclusion
In this tutorial, we looked at the Circular View path error, why it happens, and how to resolve the issue. As always, the full source code of the article is available over on GitHub.