* Enable additional Error Prone checks & fix violations
Some of them also enforce additional Google Java Format requirements which
are not handled by google-java-format, such as disallowing wildcard imports.
Not all experimental checks have been listed because some are not applicable,
such as Dependency Injection framework checks, or checks related to Guava's
immutable collections (since Gson's main code does not have a dependency on
Guava).
Other checks have been omitted because they are probably not relevant
(this was a subjective choice), or would require larger refactoring or
would flag issues with the public API, which cannot be changed easily.
* Address review feedback
---------
Co-authored-by: Éamonn McManus <emcmanus@google.com>
Consolidated all of the different code paths that we use to construct instances. We now have an ObjectConstructor class that knows what type it constructs; this means that we don't need to ever do reflection to lookup a constructor at construction time.
Cleaned up some buggy type adapters, particularly around handling of null.
Removed dead code for object graph navigation.
Moved some classes into 'internal' so they are visible to the 'bind' subpackage.
Turned some TypeAdapterFactory/TypeAdapter pairs inside out so that the TypeAdapter is now the inner class. This is necessary so that the factories can take parameters.
Added an API to request the 'next' type adapter for a type. This allows type adapters to compose other type adapters. We're using this in two places:
- where the user has excluded a type from serialization but not deserialization, we need to use the "default" deserialization but interpose null on serialization. We create a type adapter that delegates for one and returns null for the other.
- similarly when a DOM type serializer is registered but no deserializer, or vice versa.
This is the biggest change to the MiniGson core.
For backwards compatibility, return null for the empty string.
Simplify JsonSerializationContext/JsonDeserializationContext to simply call through to GSON. SerializeDefault is currently unsupported.
More useful error messages when calling getAsBoolean on a JsonNull.
Remove currently unused MemoryRefStack. We might need this back again, though wiring it back in will be much more difficult because we don't interject ourselves between the users' various type adapters.
