How to implement @RequestMapping custom properties
java, servlets, spring, spring-mvc
Solution
I've created solution based on referenced spring-mvc-31-demo
This solution can be used to map only single RequestCondition as of now. I've created two Issues to notify, this should be changed: https://github.com/rstoyanchev/spring-mvc-31-demo/issues/5 https://jira.springsource.org/browse/SPR-9350
This solution uses custom @RequestCondition feature of Spring 3.1.1.RELEASE platform
USAGE
Example 1:
@Controller
@SubdomainMapping(value = "subdomain", tld = ".mydomain.com")
class MyController1 {
// Code here will be executed only on address match:
// subdomain.mydomain.com
}
Example 2:
@Controller
class MyController2 {
@RequestMapping("/index.html")
@SubdomainMapping("www")
public function index_www(Map<Object, String> map){
// on www.domain.com
// where ".domain.com" is defined in SubdomainMapping.java
}
@RequestMapping("/index.html")
@SubdomainMapping("custom")
public function index_custom(Map<Object, String> map){
// on custom.domain.com
// where ".domain.com" is defined in SubdomainMapping.java
}
}
We need three files
- SubdomainMapping.java
- SubdomainRequestCondition.java
- SubdomainRequestMappingHandlerMapping.java
SubdomainMapping.java
import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
@Target({ElementType.METHOD, ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
public @interface SubdomainMapping {
/**
* This param defines single or multiple subdomain
* Where the Method/Type is valid to be called
*/
String[] value() default {};
/**
* This param defines site domain and tld
* It's important to put the leading dot
* Not an array, so cannot be used for mapping multiple domains/tld
*/
String tld() default ".custom.tld";
}
SubdomainRequestCondition.java
import java.net.URL;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.LinkedHashSet;
import java.util.Set;
import javax.servlet.http.HttpServletRequest;
import org.springframework.web.servlet.mvc.condition.RequestCondition;
public class SubdomainRequestCondition implements
RequestCondition<SubdomainRequestCondition> {
private final Set<String> subdomains;
private final String tld;
public SubdomainRequestCondition(String tld, String... subdomains) {
this(tld, Arrays.asList(subdomains));
}
public SubdomainRequestCondition(String tld, Collection<String> subdomains) {
this.subdomains = Collections.unmodifiableSet(new HashSet<String>(
subdomains));
this.tld = tld;
}
@Override
public SubdomainRequestCondition combine(SubdomainRequestCondition other) {
Set<String> allRoles = new LinkedHashSet<String>(this.subdomains);
allRoles.addAll(other.subdomains);
return new SubdomainRequestCondition(tld, allRoles);
}
@Override
public SubdomainRequestCondition getMatchingCondition(
HttpServletRequest request) {
try {
URL uri = new URL(request.getRequestURL().toString());
String[] parts = uri.getHost().split(this.tld);
if (parts.length == 1) {
for (String s : this.subdomains) {
if (s.equalsIgnoreCase(parts[0])) {
return this;
}
}
}
} catch (Exception e) {
e.printStackTrace(System.err);
}
return null;
}
@Override
public int compareTo(SubdomainRequestCondition other,
HttpServletRequest request) {
return org.apache.commons.collections.CollectionUtils.removeAll(other.subdomains, this.subdomains).size();
}
}
SubdomainRequestMappingHandlerMapping.java
import java.lang.reflect.Method;
import org.springframework.core.annotation.AnnotationUtils;
import org.springframework.web.servlet.mvc.condition.RequestCondition;
import org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping;
public class CustomRequestMappingHandlerMapping extends
RequestMappingHandlerMapping {
@Override
protected RequestCondition<?> getCustomTypeCondition(Class<?> handlerType) {
SubdomainMapping typeAnnotation = AnnotationUtils.findAnnotation(
handlerType, SubdomainMapping.class);
return createCondition(typeAnnotation);
}
@Override
protected RequestCondition<?> getCustomMethodCondition(Method method) {
SubdomainMapping methodAnnotation = AnnotationUtils.findAnnotation(
method, SubdomainMapping.class);
return createCondition(methodAnnotation);
}
private RequestCondition<?> createCondition(SubdomainMapping accessMapping) {
return (accessMapping != null) ? new SubdomainRequestCondition(
accessMapping.tld(), accessMapping.value()) : null;
}
}
Instalation
IMPORTANT: So far, it is not possible to use this solution with XML element <mvc:annotation-driven />, see JIRA https://jira.springsource.org/browse/SPR-9344 for explanation
- You have to register custom MappingHandler bean, pointing at this custom implementation `SubdomainRequestMappingHandlerMapping` class
- You have to set it's order to be lower than default `RequestMappingHandlerMapping` OR Replace the registered `RequestMappingHandlerMapping` (possibly on order=0)
For more wide explanation on implementing this solution, see the related github project
Problem
As an example, take subdomain mapping. This article: Managing multiple Domain and Sub Domain on Google App Engine for Same Application recommends to resolve subdomain on Filter and assign variable to ServletRequest headers. Then the mapping will look like this: ``` @RequestMapping(value = "/path", headers="subdomain=www") public String subsiteIndexPage(Model model,HttpServletRequest request) { ... } ``` If we'd like to create custom @RequestMapping property, such as subdomain, eg. to create mapping like this: ``` @RequestMapping(value = "/some/action", subdomain = "www") public String handlerFunction(){ ... } ``` we should override `@RequestMapping @interface` definition and override RequestMappingHandlerMapping protected methods, with our own implementation (as stated on JIRA: "Allow custom request mapping conditions SPR-7812"). Is it right? Can anybody provide a hint, how to achieve this functionality? Idea 1: As suggested on original jira thread, is to create own implementation of `RequestCondition` There is an project which uses this solution available on github: https://github.com/rstoyanchev/spring-mvc-31-demo/ And related SO question: Adding custom RequestCondition's in Spring mvc 3.1 Maybe mapping like `@Subdomain("www")` for both Type and Method, is possible solution? Link to same question on forum.springsource.com