[2.1.1 java] Map enum parameter in routes

[Andrea Guarini]

Hi,

I'm trying to use a custom defined Enum as a parameter type in my controllers and routes. I would like to map a portion of the request URL as an Enum.

The Enum is defined as following:

public enum Sorting implements QueryStringBindable<Sorting2>, PathBindable<Sorting2>

{

@EnumValue("I")

IMPORTANT_FIRST, 

@EnumValue("N")

NEWEST_FIRST, 

@EnumValue("O")

OLDEST_FIRST;

private Sorting value;

@Override

public Option<Sorting> bind(String key, Map<String, String[]> data)

{

String[] vs = data.get(key);

        if (vs != null && vs.length > 0) {

            String v = vs[0];

            value = Enum.valueOf(Sorting.class, v);

            return Option.Some(value);

        }

        return Option.None();

}

@Override

public String unbind(String key)

{

return key + "=" + value;

}

@Override

public String javascriptUnbind()

{

return value.toString();

}

@Override

public Sorting bind(String key, String txt)

{

        this.value = Enum.valueOf(Sorting.class, txt);

    return this;

}

}

My controller action is:

public static Result enumTest(Sorting s)

My route is:

GET  /enumTest/:s controllers.Application.enumTest2(s:full.path.to.Sorting)

My test url in the browser:

http://localhost:9000/enumTest/IMPORTANT_FIRST

Play says this:

Bad request

For request 'GET /enumTest/IMPORTANT_FIRST' [full.path.to.Sorting]

Play is compiling the code successfully and I don't get any exceptions in the console at runtime.

How can I solve this?

Thank you for your help.

[Edouard Pelosi]

The class that implements PathBindable and QueryStringBindable need to provider a noarg public constructor.

So enum cannot use it as all constuctors are private.

I solved it by wrapping it in another class like this:

enum MyEnum {

   stuff,

   thing

}

class MyWrapper implements QueryStringBindable<MyWrapper>, PathBindable<MyWrapper> {

         private MyEnum value;

        //getter setter

        @Override

        public CrudEntitiesBindable bind(String key, String txt) {

            this.value = MyEnum.valueOf(txt);

            return this;

        }

        @Override

        public F.Option<MyWrapper> bind(String key, Map<String, String[]> data) {

            String[] strings = data.get(key);

            if(strings != null && strings.length > 0){

                MyWrapper c = new MyWrapper();

                c.value = MyEnum.valueOf(strings[0]);

                return F.Some(c);

            }else{

                return F.None();

            }

        }

        @Override

        public String unbind(String key) {

            return this.value.name();

        }

        @Override

        public String javascriptUnbind() {

            return this.value.name();

[Oleg Derid]

Thanks mate for sharing the solution. Please, help with the following:

I couldn't find the CrudEntitiesBindable class import package in 2.3 play Java API reference, please advice which one is ok to use?

P.S. the following are required to resolve the rest of the entitites

import play.libs.F;

import play.mvc.PathBindable;

import play.mvc.QueryStringBindable;

import java.util.Map;