Moshi Converter

A Converter which uses Moshi for serialization to and from JSON.

Sample usage

Get a hold of SharedPreferences instance to use the extensions put and get:

lateinit var prefs: SharedPreferences
...
prefs = appContext.getSharedPreferences("test", Context.MODE_PRIVATE)

To save and load primitive types:

prefs.put("key", 1)
val a = prefs.get("key", Int::class, 1)

To save and load object types:

val list = mutableListOf(1)
val type = Types.newParameterizedType(List::class.java, Integer::class.java)

prefs.put("key", list, type)
prefs.get("key", type, mutableListOf<Int>()))

When not using primitive types you should use Types.newParameterizedType instead of T::class, for example:

    @Test
    fun getObjectWithType() {
        val list = mutableListOf(MyObjectType("string", 1, true))
        val type = Types.newParameterizedType(List::class.java, MyObjectType::class.java)

        prefs.put("key", list, type)
        assertEquals(list, prefs.get("key", type, mutableListOf<MyObjectType>()))
        assertNotEquals(list, prefs.get("key", List::class, mutableListOf<MyObjectType>()))
    }

    @Test
    fun getObjectWithType2() {
        val list = mutableListOf(1)
        val type = Types.newParameterizedType(List::class.java, Integer::class.java)

        prefs.put("key", list, type)
        assertEquals(list, prefs.get("key", type, mutableListOf<Int>()))
        assertNotEquals(list, prefs.get("key", List::class, mutableListOf<Int>()))
    }

    @Parcelize data class MyObjectType(val fieldA: String, val fieldB: Int, val fieldC: Boolean) : Parcelable

Both tests will ran to completion.

Regarding both assertNotEquals() being true, it’s because we are providing a KClass<T> instead of a Type. That will delegate the action to theStandardJsonAdapters.java instead of JsonAdapter.java. Thus, in the second test, the JsonAdapter<Double> DOUBLE_JSON_ADAPTER (case NUMBER:...) will be chosen to complete the operation.
That’s why I we get List<Double> instead of List<Integer>.

Also:

prefs.put("key", 1)
prefs.get("key", Boolean::class, false)

Will throw JsonDataException.