CODEWITHSUNDEEP
javajax-rs
Ohad
Ohad

Reputation: 1647

can we give @QueryParam of type boolean a default value null?

can we give @QueryParam of type boolean a default value null ? if yes, how do we do it?

this is how I tried to do it but I still get false as default value:

@POST
public String setMethod(
        @QueryParam("value1") @DefaultValue("null") Boolean value1)

Upvotes: 4

Views: 2841

Answers (2)

Marco Frag Delle Monache
Marco Frag Delle Monache

Reputation: 1538

I am facing the same problem, and unfortunately there isn't a direct way to solve this.

Sadly, we can't use enums because @RequestParam defaultValue and switch-case need a constant. It also can't automatically map it from "null" into the enum.

@POST
public String setMethod(
    @QueryParam("value1") @DefaultValue("null") String value1)


Boolean boolValue1 = null;    
switch(value1) {

    case "true":
        boolValue1 = Boolean.TRUE;
        break;

    case "false":
        boolValue1 = Boolean.FALSE;
        break;

    default:
        break;
}

Since there isn't a case for null, it should remain null.

Upvotes: 4

CodeScale
CodeScale

Reputation: 3314

You should try without DefaultValue. As value1 is not a primitive it should stay null.

So like this : 

@POST
public String setMethod(
        @QueryParam("value1") Boolean value1)

following the spec:

If @DefaultValue is not used in conjunction with @QueryParam, and the query parameter is not present in the request, the value will be an empty collection for List, Set, or SortedSet; null for other object types; and the default for primitive types.

Regarding your example --> new Boolean("null") is actually equals to false.

So the result is normal.

BTW : Null should not be a valid option as a Boolean is a binary value either 0 or 1. Once it crosses into the tri-state (null, false, true) it's no longer a true Boolean and maybe if it is acceptable preferable to switch to enum value.

What about something like this ?

public enum Value {
    A ,
    B,
    ABSENT
}

@POST
public String setMethod(
        @QueryParam("value1") @DefaultValue("ABSENT") Value value1)

Upvotes: 2

Related Questions