Here is an example of using the JsonValueInstantiator class from the com.fasterxml.jackson.databind package in Java to customize the instantiation of an object during deserialization:

import com.fasterxml.jackson.databind.JsonDeserializer;
import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
import com.fasterxml.jackson.databind.deser.ValueInstantiator;
import com.fasterxml.jackson.databind.deser.std.StdValueInstantiator;

@JsonDeserialize(using = MyCustomValueInstantiator.class)
public class Example {

    private String name;

    // other fields and methods
}

public class MyCustomValueInstantiator extends StdValueInstantiator {

    @Override
    public Object createUsingDefault(DeserializationContext ctxt) throws IOException {
        return new Example("default name");
    }
}

In this example, the JsonDeserialize annotation is used to specify that a custom instantiator class, MyCustomValueInstantiator, should be used to instantiate the Example class during deserialization.

The custom instantiator class MyCustomValueInstantiator is extending StdValueInstantiator and overrides the createUsingDefault method to perform custom instantiation logic for the Example class. In this case, the Example class is instantiated with a default value for the name field.

You can also use this class in combination with JsonDeserializer to apply more complex logic during deserialization.

import com.fasterxml.jackson.databind.JsonDeserializer;
import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
import com.fasterxml.jackson.databind.deser.ValueInstantiator;
import com.fasterxml.jackson.databind.deser.std.StdValueInstantiator;

@JsonDeserialize(using = MyCustomValueInstantiator.class)
public class Example {

    private String name;

    // other fields and methods
}

public class MyCustomValueInstantiator extends StdValueInstantiator {

    @Override
    public JsonDeserializer<?> createDeserializer(DeserializationContext ctxt, JavaType valueType) {
        return new MyCustomDeserializer();
    }
}

class MyCustomDeserializer extends JsonDeserializer<Example> {

    @Override
    public Example deserialize(JsonParser p, DeserializationContext ctxt) throws IOException {
        JsonNode node = p.getCodec().readTree(p);
        String name = node.get("name").asText();
        return new Example(name + "_custom");
    }
}

In this example, the MyCustomValueInstantiator class is extending StdValueInstantiator and overrides the createDeserializer method to return a custom deserializer MyCustomDeserializer class, this class is responsible for deserializing the Example class, in this case, we are just adding "_custom"