com.evrythng.java.wrapper.mapping.PropertyDeserializer.java Source code

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Here is the source code for com.evrythng.java.wrapper.mapping.PropertyDeserializer.java

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/*
 * (c) Copyright Reserved EVRYTHNG Limited 2016. All rights reserved.
 * Use of this material is subject to license.
 * Copying and unauthorised use of this material strictly prohibited.
 */
package com.evrythng.java.wrapper.mapping;

import com.evrythng.java.wrapper.util.JSONUtils;
import com.evrythng.thng.resource.model.store.ArrayProperty;
import com.evrythng.thng.resource.model.store.BooleanProperty;
import com.evrythng.thng.resource.model.store.NumberProperty;
import com.evrythng.thng.resource.model.store.ObjectProperty;
import com.evrythng.thng.resource.model.store.Property;
import com.evrythng.thng.resource.model.store.StringProperty;
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.deser.std.StdDeserializer;

import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;

public class PropertyDeserializer extends StdDeserializer<Property<?>> {

    private static final long serialVersionUID = 272184685620984657L;

    protected PropertyDeserializer() {

        super(Property.class);
    }

    @Override
    public Property<?> deserialize(final JsonParser jp, final DeserializationContext ctx) throws IOException {

        ObjectMapper mapper = JSONUtils.OBJECT_MAPPER;
        JsonNode node = mapper.readTree(jp);
        JsonNode valueNode = node.get(Property.FIELD_VALUE);
        if (valueNode == null) {
            throw new JsonMappingException("Cannot deserialize property without value field");
        }
        Object value = getFieldValue(valueNode);
        Property.Type type = Property.Type.forPropertyValue(value);
        Class<? extends Property<?>> propertyClass = propertyClassForType(type);
        return mapper.readValue(node.toString(), propertyClass);
    }

    private Class<? extends Property<?>> propertyClassForType(final Property.Type type) {

        switch (type) {
        case BOOLEAN:
            return BooleanProperty.class;
        case STRING:
            return StringProperty.class;
        case NUMBER:
            return NumberProperty.class;
        case ARRAY:
            return ArrayProperty.class;
        case OBJECT:
            return ObjectProperty.class;
        }
        throw new IllegalArgumentException("Unsupported property type: " + type);
    }

    private Object getFieldValue(final JsonNode node) {

        if (node == null) {
            return null;
        }
        Object value = null;
        if (node.isBoolean()) {
            value = node.asBoolean();
        }
        if (node.isNumber()) {
            value = node.asDouble();
        }
        if (node.isTextual()) {
            value = node.asText();
        }
        if (node.isArray()) {
            value = new ArrayList<>();
        }
        if (node.isObject()) {
            value = new HashMap<>();
        }
        return value;
    }
}