org.apache.olingo.commons.core.serialization.JsonDeltaDeserializer.java Source code

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Here is the source code for org.apache.olingo.commons.core.serialization.JsonDeltaDeserializer.java

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/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you 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 org.apache.olingo.commons.core.serialization;

import com.fasterxml.jackson.core.JsonFactory;
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.node.ObjectNode;
import org.apache.commons.lang3.StringUtils;
import org.apache.olingo.commons.api.Constants;
import org.apache.olingo.commons.api.data.ContextURL;
import org.apache.olingo.commons.api.data.Delta;
import org.apache.olingo.commons.api.data.ResWrap;
import org.apache.olingo.commons.api.edm.constants.ODataServiceVersion;
import org.apache.olingo.commons.api.serialization.ODataDeserializerException;
import org.apache.olingo.commons.core.data.DeletedEntityImpl;
import org.apache.olingo.commons.core.data.DeltaLinkImpl;
import org.apache.olingo.commons.core.data.v4.DeltaImpl;

import java.io.IOException;
import java.io.InputStream;
import java.net.URI;

public class JsonDeltaDeserializer extends JsonDeserializer {

    public JsonDeltaDeserializer(final ODataServiceVersion version, final boolean serverMode) {
        super(version, serverMode);
    }

    protected ResWrap<Delta> doDeserialize(final JsonParser parser) throws IOException {

        final ObjectNode tree = parser.getCodec().readTree(parser);

        final DeltaImpl delta = new DeltaImpl();

        final URI contextURL = tree.hasNonNull(Constants.JSON_CONTEXT)
                ? URI.create(tree.get(Constants.JSON_CONTEXT).textValue())
                : null;
        if (contextURL != null) {
            delta.setBaseURI(StringUtils.substringBefore(contextURL.toASCIIString(), Constants.METADATA));
        }

        if (tree.hasNonNull(jsonCount)) {
            delta.setCount(tree.get(jsonCount).asInt());
        }
        if (tree.hasNonNull(jsonNextLink)) {
            delta.setNext(URI.create(tree.get(jsonNextLink).textValue()));
        }
        if (tree.hasNonNull(jsonDeltaLink)) {
            delta.setDeltaLink(URI.create(tree.get(jsonDeltaLink).textValue()));
        }

        if (tree.hasNonNull(Constants.VALUE)) {
            JsonEntityDeserializer entityDeserializer = new JsonEntityDeserializer(version, serverMode);
            for (JsonNode jsonNode : tree.get(Constants.VALUE)) {
                final ObjectNode item = (ObjectNode) jsonNode;
                final ContextURL itemContextURL = item.hasNonNull(Constants.JSON_CONTEXT)
                        ? ContextURLParser.parse(URI.create(item.get(Constants.JSON_CONTEXT).textValue()))
                        : null;
                item.remove(Constants.JSON_CONTEXT);

                if (itemContextURL == null || itemContextURL.isEntity()) {
                    delta.getEntities()
                            .add(entityDeserializer.doDeserialize(item.traverse(parser.getCodec())).getPayload());
                } else if (itemContextURL.isDeltaDeletedEntity()) {
                    delta.getDeletedEntities().add(parser.getCodec().treeToValue(item, DeletedEntityImpl.class));
                } else if (itemContextURL.isDeltaLink()) {
                    delta.getAddedLinks().add(parser.getCodec().treeToValue(item, DeltaLinkImpl.class));
                } else if (itemContextURL.isDeltaDeletedLink()) {
                    delta.getDeletedLinks().add(parser.getCodec().treeToValue(item, DeltaLinkImpl.class));
                }
            }
        }

        return new ResWrap<Delta>(contextURL, null, delta);
    }

    public ResWrap<Delta> toDelta(final InputStream input) throws ODataDeserializerException {
        try {
            JsonParser parser = new JsonFactory(new ObjectMapper()).createParser(input);
            return doDeserialize(parser);
        } catch (final IOException e) {
            throw new ODataDeserializerException(e);
        }
    }
}