Moshi: Expected a Class, ParameterizedType, or GenericArrayType, but is of type null

Question

I have this model:

class Model1 {
    <... other fields here ...>
    var attributes: Map<String, Any>? = null
    <... other fields here ...>
}

I expect a list of these models.

Sample JSON:

[
    {
        "attributes": {
            "title": "New Year's Day",
            "country": "SG"
        }
    },
    {
        "attributes": {
            "staff_id": 320011,
            "title": "Labor day",
            "date_joined": "2017-01-10 00:00:00",
            "years": 1
        }
    }
]

Then I get this error during deserialization:

Caused by: java.lang.IllegalArgumentException: Expected a Class, ParameterizedType, or GenericArrayType, but <null> is of type null
    at com.squareup.moshi.Types.getRawType(Types.java:165)
    at com.squareup.moshi.ClassJsonAdapter$1.createFieldBindings(ClassJsonAdapter.java:82)
    at com.squareup.moshi.ClassJsonAdapter$1.create(ClassJsonAdapter.java:74)
    at com.squareup.moshi.Moshi.adapter(Moshi.java:99)
    at com.squareup.moshi.Moshi.adapter(Moshi.java:57)
    at com.squareup.moshi.MapJsonAdapter.<init>(MapJsonAdapter.java:46)
    at com.squareup.moshi.MapJsonAdapter$1.create(MapJsonAdapter.java:37)
    at com.squareup.moshi.Moshi.adapter(Moshi.java:99)
    at com.squareup.moshi.ClassJsonAdapter$1.createFieldBindings(ClassJsonAdapter.java:90)
    at com.squareup.moshi.ClassJsonAdapter$1.create(ClassJsonAdapter.java:74)
    at com.squareup.moshi.Moshi.adapter(Moshi.java:99)
    at com.squareup.moshi.Moshi.adapter(Moshi.java:57)
    at com.squareup.moshi.CollectionJsonAdapter.newArrayListAdapter(CollectionJsonAdapter.java:51)
    at com.squareup.moshi.CollectionJsonAdapter$1.create(CollectionJsonAdapter.java:35)
    at com.squareup.moshi.Moshi.adapter(Moshi.java:99)
    at com.squareup.moshi.ClassJsonAdapter$1.createFieldBindings(ClassJsonAdapter.java:90)
    at com.squareup.moshi.ClassJsonAdapter$1.create(ClassJsonAdapter.java:74)
    at com.squareup.moshi.Moshi.adapter(Moshi.java:99)
    at retrofit2.converter.moshi.MoshiConverterFactory.responseBodyConverter(MoshiConverterFactory.java:91)
    at retrofit2.Retrofit.nextResponseBodyConverter(Retrofit.java:330)
    at retrofit2.Retrofit.responseBodyConverter(Retrofit.java:313)
    at retrofit2.ServiceMethod$Builder.createResponseConverter(ServiceMethod.java:736)
        ... 65 more

I need the field attribute to be a map. The data inside could be any type and any value

There is similar issue on github https://github.com/square/moshi/issues/309 You can take a look at the PR — Raghunandan, Dec 12 '17 at 09:24

score 6 · Answer 1 · answered Dec 13 '17 at 00:39

6

You want @JvmSuppressWildcards on the Map parameters. https://github.com/square/moshi/issues/410#issuecomment-351131524

Hopefully, a better error message will show up in the next version of Moshi.

answered Dec 13 '17 at 00:39

Eric Cochran

8,414
5
50
91

score 2 · Accepted Answer · answered Dec 13 '17 at 03:47

2

Just need to do this:

class Model1 {
    <... other fields here ...>
    @JvmSuppressWildcards var attributes: Map<String, Any>? = null
    <... other fields here ...>
}

https://github.com/square/moshi/issues/410#issuecomment-351131524

answered Dec 13 '17 at 03:47

iadcialim24

3,817
5
21
32

Moshi: Expected a Class, ParameterizedType, or GenericArrayType, but is of type null

2 Answers2