Java Google Json (Gson) Type Adapter

Using Custom Type Adapter

In the earlier tutorials we have seen how gson can serialize and deserialize java classes with or without hierarchies. By default, it introspects the classes and comes with with a strategy for serializing and deserializing it. However, in some cases, you want to specify your own conversion strategy. That is, you want to control how the java object is converted to json string and the other way round. Gson provides a capability to specify a custom type adapter. You tell Gson that for a particular class, use the conversion strategy specified by your custom adapter. Lets look at how to write the type adapter :
To write a custom adapter extend the com.google.gson.TypeAdapter abstract class. Implement the public abstract T read(JsonReader in) throws IOException; and public abstract void write(JsonWriter out, T value) throws IOException; methods. The adapter should also handle nulls. Create the Type adapter
instance and then register it with the GsonBuilder. Create the Gson object from the GsonBuilder and then use that to serialize and deserialize. Lets look at an example

The Adapter

The Albums class

The Dataset class

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