package com.facebook.presto.jdbc.internal.jackson.databind.node;
import java.io.IOException;
import com.facebook.presto.jdbc.internal.jackson.core.*;
import com.facebook.presto.jdbc.internal.jackson.databind.JsonNode;
import com.facebook.presto.jdbc.internal.jackson.databind.JsonSerializable;
import com.facebook.presto.jdbc.internal.jackson.databind.SerializerProvider;
import com.facebook.presto.jdbc.internal.jackson.databind.jsontype.TypeSerializer;
/**
* Abstract base class common to all standard {@link JsonNode}
* implementations.
* The main addition here is that we declare that sub-classes must
* implement {@link JsonSerializable}.
* This simplifies object mapping aspects a bit, as no external serializers are needed.
*/
public abstract class BaseJsonNode
extends JsonNode
implements JsonSerializable
{
protected BaseJsonNode() { }
/*
/**********************************************************
/* Basic definitions for non-container types
/**********************************************************
*/
@Override
public final JsonNode findPath(String fieldName)
{
JsonNode value = findValue(fieldName);
if (value == null) {
return MissingNode.getInstance();
}
return value;
}
/*
/**********************************************************
/* Support for traversal-as-stream
/**********************************************************
*/
@Override
public JsonParser traverse() {
return new TreeTraversingParser(this);
}
@Override
public JsonParser traverse(ObjectCodec codec) {
return new TreeTraversingParser(this, codec);
}
/**
* Method that can be used for efficient type detection
* when using stream abstraction for traversing nodes.
* Will return the first {@link JsonToken} that equivalent
* stream event would produce (for most nodes there is just
* one token but for structured/container types multiple)
*/
@Override
public abstract JsonToken asToken();
/**
* Returns code that identifies type of underlying numeric
* value, if (and only if) node is a number node.
*/
@Override
public JsonParser.NumberType numberType() {
// most types non-numeric, so:
return null;
}
/*
/**********************************************************
/* JsonSerializable
/**********************************************************
*/
/**
* Method called to serialize node instances using given generator.
*/
@Override
public abstract void serialize(JsonGenerator jgen, SerializerProvider provider)
throws IOException, JsonProcessingException;
/**
* Type information is needed, even if JsonNode instances are "plain" JSON,
* since they may be mixed with other types.
*/
@Override
public abstract void serializeWithType(JsonGenerator jgen, SerializerProvider provider,
TypeSerializer typeSer)
throws IOException, JsonProcessingException;
}