@PathVariable List<UUID> in Spring MVC

Question

In a Spring MVC controller a @PathVariable Long... ids get resolved fine when passed input like 1,2,3.

If the parameter is declared as @PathVariable UUID... ids then the comma-separation doesn't work: a 400 response is returned.

Can I implement a custom PropertyEditor to handle UUID[] or List<UUID>? The only examples I can find are for single values, not collections/arrays.

UPDATE

As per Phil Webb's answer below, after reporting the issue as a bug on the Spring JIRA, the kind folks at SpringSource added support for this in Spring 3.2

Answer 1

This issue will be fixed in Spring 3.2. See https://jira.springsource.org/browse/SPR-9765 for details.

Answer 2

You can register a custom converter this way:

import org.springframework.core.convert.converter.Converter;
class UUIDConverter implements Converter<String, UUID> {

    @Override
    public UUID convert(String source) {
        return UUID.fromString(source);
    }

}

and register it with Spring MVC:

<bean id="conversionService" class="org.springframework.format.support.FormattingConversionServiceFactoryBean">
    <property name="converters">
        <set>
            <bean class="....UUIDConverter"/>
        </set>
    </property>
</bean>


<mvc:annotation-driven conversion-service="conversionService"> 
</mvc:annotation-driven>

Now if you submit UUID's it should get correctly mapped to a list.

Answer 3

For annotation based configuration you just need to add @Component annotation to the class

package com.demo.config.converters;
import org.springframework.core.convert.converter.Converter;
import org.springframework.stereotype.Component;
import java.util.UUID;

@Component
public class StringToUUIDConvertor
  implements Converter<String, UUID> {

    @Override
    public UUID convert(String source) {
        try {
            return UUID.fromString(source);
        }
        // just changing default message to the one I like to see.
        catch (IllegalArgumentException ex){
            throw new IllegalArgumentException("Invalid input UUID string");
        }
    }
}