com.fasterxml.jackson.databind.deser.DefaultDeserializationContext Maven / Gradle / Ivy

package com.fasterxml.jackson.databind.deser;

import java.util.*;
import java.util.Map.Entry;

import com.fasterxml.jackson.annotation.ObjectIdGenerator;
import com.fasterxml.jackson.annotation.ObjectIdResolver;
import com.fasterxml.jackson.annotation.ObjectIdGenerator.IdKey;

import com.fasterxml.jackson.core.JsonParser;

import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.databind.cfg.HandlerInstantiator;
import com.fasterxml.jackson.databind.deser.impl.ReadableObjectId;
import com.fasterxml.jackson.databind.deser.impl.ReadableObjectId.Referring;
import com.fasterxml.jackson.databind.introspect.Annotated;
import com.fasterxml.jackson.databind.util.ClassUtil;

/**
 * Complete {@link DeserializationContext} implementation that adds
 * extended API for {@link ObjectMapper} (and {@link ObjectReader})
 * to call, as well as implements certain parts that base class
 * has left abstract.
 * The remaining abstract methods ({@link #createInstance}, {@link #with})
 * are left so that custom implementations will properly implement them
 * to return intended subtype.
 */
public abstract class DefaultDeserializationContext
    extends DeserializationContext
    implements java.io.Serializable // since 2.1
{
    private static final long serialVersionUID = 1L;

    protected transient LinkedHashMap _objectIds;

    private List _objectIdResolvers;

    /**
     * Constructor that will pass specified deserializer factory and
     * cache: cache may be null (in which case default implementation
     * will be used), factory cannot be null
     */
    protected DefaultDeserializationContext(DeserializerFactory df, DeserializerCache cache) {
        super(df, cache);
    }
    
    protected DefaultDeserializationContext(DefaultDeserializationContext src,
            DeserializationConfig config, JsonParser jp, InjectableValues values) {
        super(src, config, jp, values);
    }

    protected DefaultDeserializationContext(DefaultDeserializationContext src,
            DeserializerFactory factory) {
        super(src, factory);
    }

    /**
     * @since 2.4.4
     */
    protected DefaultDeserializationContext(DefaultDeserializationContext src) {
        super(src);
    }
    
    /**
     * Method needed to ensure that {@link ObjectMapper#copy} will work
     * properly; specifically, that caches are cleared, but settings
     * will otherwise remain identical; and that no sharing of state
     * occurs.
     * 
     * @since 2.4.4
     */
    public DefaultDeserializationContext copy() {
        throw new IllegalStateException("DefaultDeserializationContext sub-class not overriding copy()");
    }

    /*
    /**********************************************************
    /* Abstract methods impls, Object Id
    /**********************************************************
     */

    @Override
    public ReadableObjectId findObjectId(Object id, ObjectIdGenerator gen, ObjectIdResolver resolverType)
    {
        /* 02-Apr-2015, tatu: As per [databind#742] should allow 'null', similar to how
         *   missing id already works.
         */
        if (id == null) {
            return null;
        }

        final ObjectIdGenerator.IdKey key = gen.key(id);

        if (_objectIds == null) {
            _objectIds = new LinkedHashMap();
        } else {
            ReadableObjectId entry = _objectIds.get(key);
            if (entry != null) {
                return entry;
            }
        }

        // Not seen yet, must create entry and configure resolver.
        ObjectIdResolver resolver = null;

        if (_objectIdResolvers == null) {
            _objectIdResolvers = new ArrayList(8);
        } else {
            for (ObjectIdResolver res : _objectIdResolvers) {
                if (res.canUseFor(resolverType)) {
                    resolver = res;
                    break;
                }
            }
        }

        if (resolver == null) {
            resolver = resolverType.newForDeserialization(this);
            _objectIdResolvers.add(resolver);
        }

        ReadableObjectId entry = createReadableObjectId(key);
        entry.setResolver(resolver);
        _objectIds.put(key, entry);
        return entry;
    }

    /**
     * Overridable factory method to create a new instance of ReadableObjectId or its
     * subclass. It is meant to be overridden when custom ReadableObjectId is
     * needed for {@link #tryToResolveUnresolvedObjectId}.
     * Default implementation simply constructs default {@link ReadableObjectId} with
     * given key.
     * 
     * @param key The key to associate with the new ReadableObjectId
     * @return New ReadableObjectId instance
     *
     * @since 2.7
     */
    protected ReadableObjectId createReadableObjectId(IdKey key) {
        return new ReadableObjectId(key);
    }

    @Override
    public void checkUnresolvedObjectId() throws UnresolvedForwardReference
    {
        if (_objectIds == null) {
            return;
        }
        // 29-Dec-2014, tatu: As per [databind#299], may also just let unresolved refs be...
        if (!isEnabled(DeserializationFeature.FAIL_ON_UNRESOLVED_OBJECT_IDS)) {
            return;
        }
        UnresolvedForwardReference exception = null;
        for (Entry entry : _objectIds.entrySet()) {
            ReadableObjectId roid = entry.getValue();
            if (!roid.hasReferringProperties()) {
                continue;
            }
            // as per [databind#675], allow resolution at this point
            if (tryToResolveUnresolvedObjectId(roid)) {
                continue;
            }
            if (exception == null) {
                exception = new UnresolvedForwardReference(getParser(), "Unresolved forward references for: ");
            }
            Object key = roid.getKey().key;
            for (Iterator iterator = roid.referringProperties(); iterator.hasNext(); ) {
                Referring referring = iterator.next();
                exception.addUnresolvedId(key, referring.getBeanType(), referring.getLocation());
            }
        }
        if (exception != null) {
            throw exception;
        }
    }

    /**
     * Overridable helper method called to try to resolve otherwise unresolvable {@link ReadableObjectId};
     * and if this succeeds, return true to indicate problem has been resolved in
     * some way, so that caller can avoid reporting it as an error.
     *
     * Default implementation simply calls {@link ReadableObjectId#tryToResolveUnresolved} and
     * returns whatever it returns.
     *
     * @since 2.6
     */
    protected boolean tryToResolveUnresolvedObjectId(ReadableObjectId roid)
    {
        return roid.tryToResolveUnresolved(this);
    }
    
    /*
    /**********************************************************
    /* Abstract methods impls, other factory methods
    /**********************************************************
     */
    
    @SuppressWarnings("unchecked")
    @Override
    public JsonDeserializer