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Other than RedirectView , Spring provides another option to perform redirection, that is return redirected url as String with prefix 'redirect:'
The net effect is the same as if the controller had returned a RedirectView, but with this option the controller itself can simply operate in terms of logical view names.
The prefix 'redirect:' is a special directive for the view resolver to treat the returned string as URL redirection rather than as a view name.
A logical view name such as redirect:/some/resource will redirect relative to the current Servlet context, while a name such as redirect:http://www.example.com/path will redirect to an absolute URL.
The controller conditionally can return a view name or redirected URL.
By default status code 302 is sent. If we want to change that we can annotate the return type of handler method with @ResponseStatus(..).
Following example demonstrates the use of 'redirect:'
The Controller
In this example: if the path template variable 'id' consists of digits then redirect to different URL otherwise return the error page view name.
@Controller
public class MyController {
@RequestMapping(value = "test/{id}")
public String handleTestRequest (@PathVariable("id") String id, Model model) {
if (!id.matches("\\d+")) {
model.addAttribute("msg", "id should only have digits");
return "error-page";
} else {
model.addAttribute("attr", "attrVal");
return "redirect:/test2/{id}";
}
}
@RequestMapping("test2/{id}")
public String handleRequest (@PathVariable("id") String id,
@RequestParam("attr") String attr,
Model model) {
model.addAttribute("id", id);
model.addAttribute("attr", attr);
return "my-page";
}
}
my-page.jsp
<%@ page language="java"
contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<html>
<body>
<p> id : ${id}</p>
<p> attr : ${attr}</p>
</body>
</html>
error-page.jsp
<%@ page language="java"
contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<html>
<body>
<p style="color:red;"> Error message : ${msg}</p>
</body>
</html>
Example Project
Dependencies and Technologies Used: - Spring Web MVC 4.2.4.RELEASE: Spring Web MVC.
- Java Servlet API 3.0.1
- Spring TestContext Framework 4.2.4.RELEASE: Spring TestContext Framework.
- JUnit 4.12: JUnit is a unit testing framework for Java, created by Erich Gamma and Kent Beck.
- JDK 1.8
- Maven 3.0.4
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