com.strategicgains.hyperexpress.serialization.siren.jackson.SirenResourceDeserializer.java Source code

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Here is the source code for com.strategicgains.hyperexpress.serialization.siren.jackson.SirenResourceDeserializer.java

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/*
Copyright 2014, Strategic Gains, Inc.
    
   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at
    
  http://www.apache.org/licenses/LICENSE-2.0
    
   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
 */
package com.strategicgains.hyperexpress.serialization.siren.jackson;

import java.io.IOException;
import java.util.Arrays;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;

import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.core.ObjectCodec;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JsonDeserializer;
import com.fasterxml.jackson.databind.JsonNode;
import com.strategicgains.hyperexpress.builder.LinkBuilder;
import com.strategicgains.hyperexpress.domain.Namespace;
import com.strategicgains.hyperexpress.domain.siren.SirenResource;

/**
 * @author toddf
 * @since Sep 12, 2014
 */
public class SirenResourceDeserializer extends JsonDeserializer<SirenResource> {
    private static final String CLASS = "class";
    private static final String TITLE = "title";
    private static final String PROPERTIES = "properties";
    private static final String ENTITIES = "entities";
    private static final String LINKS = "links";
    private static final String ACTIONS = "actions";
    //   private static final String NAME = "name";
    //   private static final String METHOD = "method";
    //   private static final String HREF = "href";
    //   private static final String TYPE = "type";
    private static final String FIELDS = "fields";

    @Override
    public SirenResource deserialize(JsonParser jp, DeserializationContext context)
            throws IOException, JsonProcessingException {
        ObjectCodec oc = jp.getCodec();
        return deserializeResource((JsonNode) jp.readValueAsTree(), oc);
    }

    private SirenResource deserializeResource(JsonNode root, ObjectCodec oc)
            throws JsonProcessingException, IOException {
        SirenResource resource = new SirenResource();
        processClass(root.get(CLASS), resource, oc);
        processTitle(root.get(TITLE), resource, oc);
        processLinks(root.get(LINKS), resource, oc);
        processEntities(root.get(ENTITIES), resource, oc);
        processProperties(root.get(PROPERTIES), resource);
        processActions(root.get(ACTIONS), resource, oc);
        return resource;
    }

    private void processClass(JsonNode jsonNode, SirenResource resource, ObjectCodec oc) {
    }

    private void processTitle(JsonNode jsonNode, SirenResource resource, ObjectCodec oc) {
    }

    /**
     * @param links
     * @param resource
     * @param oc 
     * @throws IOException
     * @throws JsonProcessingException
     */
    private void processLinks(JsonNode links, SirenResource resource, ObjectCodec oc)
            throws JsonProcessingException, IOException {
        if (links == null)
            return;

        Iterator<Entry<String, JsonNode>> fields = links.fields();

        while (fields.hasNext()) {
            Entry<String, JsonNode> field = fields.next();

            if (field.getValue().isArray()) {
                addAllLinks(resource, field);
            } else {
                addLink(resource, field);
            }
        }
    }

    /**
     * @param resource
     * @param field
     */
    private void addAllLinks(SirenResource resource, Entry<String, JsonNode> field) {
        LinkBuilder lb = new LinkBuilder();
        lb.rel(field.getKey());
        Iterator<JsonNode> values = field.getValue().elements();

        while (values.hasNext()) {
            JsonNode value = values.next();
            Iterator<JsonNode> elements = value.elements();

            while (elements.hasNext()) {
                JsonNode element = elements.next();
                lb.set(element.asText(), element.textValue());
            }

            resource.addLink(lb.build());
            lb.clearAttributes();
        }
    }

    /**
     * @param resource
     * @param field
     */
    private void addLink(SirenResource resource, Entry<String, JsonNode> field) {
        LinkBuilder lb = new LinkBuilder();
        lb.rel(field.getKey());
        Iterator<Entry<String, JsonNode>> elements = field.getValue().fields();

        while (elements.hasNext()) {
            Entry<String, JsonNode> element = elements.next();

            if ("href".equals(element.getKey())) {
                lb.urlPattern(element.getValue().asText());
            } else {
                lb.set(element.getKey(), element.getValue().asText());
            }
        }

        resource.addLink(lb.build());

    }

    private void processEntities(JsonNode embedded, SirenResource resource, ObjectCodec oc)
            throws JsonProcessingException, IOException {
        if (embedded == null)
            return;

        Iterator<Map.Entry<String, JsonNode>> fields = embedded.fields();

        while (fields.hasNext()) {
            Map.Entry<String, JsonNode> fieldEntry = fields.next();

            if (fieldEntry.getValue().isArray()) {
                Iterator<JsonNode> values = fieldEntry.getValue().elements();

                while (values.hasNext()) {
                    JsonNode value = values.next();
                    resource.addResource(fieldEntry.getKey(), deserializeResource(value, oc));
                }
            } else {
                resource.addResource(fieldEntry.getKey(), deserializeResource(fieldEntry.getValue(), oc));
            }
        }
    }

    private void processProperties(JsonNode root, SirenResource resource) {
        Iterator<Entry<String, JsonNode>> fields = root.fields();

        while (fields.hasNext()) {
            Entry<String, JsonNode> fieldEntry = fields.next();
            resource.setProperty(fieldEntry.getKey(), fieldEntry.getValue().asText());
        }
    }

    private void processActions(JsonNode jsonNode, SirenResource resource, ObjectCodec oc) {
        // TODO Auto-generated method stub

    }
}