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package com.fasterxml.jackson.databind.deser.std;

import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.util.*;

import com.fasterxml.jackson.core.*;
import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.databind.annotation.JacksonStdImpl;
import com.fasterxml.jackson.databind.deser.*;
import com.fasterxml.jackson.databind.deser.impl.PropertyBasedCreator;
import com.fasterxml.jackson.databind.deser.impl.PropertyValueBuffer;
import com.fasterxml.jackson.databind.deser.impl.ReadableObjectId.Referring;
import com.fasterxml.jackson.databind.jsontype.TypeDeserializer;
import com.fasterxml.jackson.databind.util.ArrayBuilders;

/**
 * Basic serializer that can take JSON "Object" structure and
 * construct a {@link java.util.Map} instance, with typed contents.
 *

* Note: for untyped content (one indicated by passing Object.class * as the type), {@link UntypedObjectDeserializer} is used instead. * It can also construct {@link java.util.Map}s, but not with specific * POJO types, only other containers and primitives/wrappers. */ @JacksonStdImpl public class MapDeserializer extends ContainerDeserializerBase> implements ContextualDeserializer, ResolvableDeserializer { private static final long serialVersionUID = -3378654289961736240L; // // Configuration: typing, deserializers protected final JavaType _mapType; /** * Key deserializer to use; either passed via constructor * (when indicated by annotations), or resolved when * {@link #resolve} is called; */ protected final KeyDeserializer _keyDeserializer; /** * Flag set to indicate that the key type is * {@link java.lang.String} (or {@link java.lang.Object}, for * which String is acceptable), and that the * default Jackson key deserializer would be used. * If both are true, can optimize handling. */ protected boolean _standardStringKey; /** * Value deserializer. */ protected final JsonDeserializer _valueDeserializer; /** * If value instances have polymorphic type information, this * is the type deserializer that can handle it */ protected final TypeDeserializer _valueTypeDeserializer; // // Instance construction settings: protected final ValueInstantiator _valueInstantiator; protected final boolean _hasDefaultCreator; /** * Deserializer that is used iff delegate-based creator is * to be used for deserializing from JSON Object. */ protected JsonDeserializer _delegateDeserializer; /** * If the Map is to be instantiated using non-default constructor * or factory method * that takes one or more named properties as argument(s), * this creator is used for instantiation. */ protected PropertyBasedCreator _propertyBasedCreator; // // Any properties to ignore if seen? protected HashSet _ignorableProperties; /* /********************************************************** /* Life-cycle /********************************************************** */ public MapDeserializer(JavaType mapType, ValueInstantiator valueInstantiator, KeyDeserializer keyDeser, JsonDeserializer valueDeser, TypeDeserializer valueTypeDeser) { super(mapType); _mapType = mapType; _keyDeserializer = keyDeser; _valueDeserializer = valueDeser; _valueTypeDeserializer = valueTypeDeser; _valueInstantiator = valueInstantiator; _hasDefaultCreator = valueInstantiator.canCreateUsingDefault(); _delegateDeserializer = null; _propertyBasedCreator = null; _standardStringKey = _isStdKeyDeser(mapType, keyDeser); } /** * Copy-constructor that can be used by sub-classes to allow * copy-on-write styling copying of settings of an existing instance. */ protected MapDeserializer(MapDeserializer src) { super(src._mapType); _mapType = src._mapType; _keyDeserializer = src._keyDeserializer; _valueDeserializer = src._valueDeserializer; _valueTypeDeserializer = src._valueTypeDeserializer; _valueInstantiator = src._valueInstantiator; _propertyBasedCreator = src._propertyBasedCreator; _delegateDeserializer = src._delegateDeserializer; _hasDefaultCreator = src._hasDefaultCreator; // should we make a copy here? _ignorableProperties = src._ignorableProperties; _standardStringKey = src._standardStringKey; } protected MapDeserializer(MapDeserializer src, KeyDeserializer keyDeser, JsonDeserializer valueDeser, TypeDeserializer valueTypeDeser, HashSet ignorable) { super(src._mapType); _mapType = src._mapType; _keyDeserializer = keyDeser; _valueDeserializer = valueDeser; _valueTypeDeserializer = valueTypeDeser; _valueInstantiator = src._valueInstantiator; _propertyBasedCreator = src._propertyBasedCreator; _delegateDeserializer = src._delegateDeserializer; _hasDefaultCreator = src._hasDefaultCreator; _ignorableProperties = ignorable; _standardStringKey = _isStdKeyDeser(_mapType, keyDeser); } /** * Fluent factory method used to create a copy with slightly * different settings. When sub-classing, MUST be overridden. */ @SuppressWarnings("unchecked") protected MapDeserializer withResolved(KeyDeserializer keyDeser, TypeDeserializer valueTypeDeser, JsonDeserializer valueDeser, HashSet ignorable) { if ((_keyDeserializer == keyDeser) && (_valueDeserializer == valueDeser) && (_valueTypeDeserializer == valueTypeDeser) && (_ignorableProperties == ignorable)) { return this; } return new MapDeserializer(this, keyDeser, (JsonDeserializer) valueDeser, valueTypeDeser, ignorable); } /** * Helper method used to check whether we can just use the default key * deserialization, where JSON String becomes Java String. */ protected final boolean _isStdKeyDeser(JavaType mapType, KeyDeserializer keyDeser) { if (keyDeser == null) { return true; } JavaType keyType = mapType.getKeyType(); if (keyType == null) { // assumed to be Object return true; } Class rawKeyType = keyType.getRawClass(); return ((rawKeyType == String.class || rawKeyType == Object.class) && isDefaultKeyDeserializer(keyDeser)); } public void setIgnorableProperties(String[] ignorable) { _ignorableProperties = (ignorable == null || ignorable.length == 0) ? null : ArrayBuilders.arrayToSet(ignorable); } /* /********************************************************** /* Validation, post-processing (ResolvableDeserializer) /********************************************************** */ @Override public void resolve(DeserializationContext ctxt) throws JsonMappingException { // May need to resolve types for delegate- and/or property-based creators: if (_valueInstantiator.canCreateUsingDelegate()) { JavaType delegateType = _valueInstantiator.getDelegateType(ctxt.getConfig()); if (delegateType == null) { throw new IllegalArgumentException("Invalid delegate-creator definition for "+_mapType +": value instantiator ("+_valueInstantiator.getClass().getName() +") returned true for 'canCreateUsingDelegate()', but null for 'getDelegateType()'"); } /* Theoretically should be able to get CreatorProperty for delegate * parameter to pass; but things get tricky because DelegateCreator * may contain injectable values. So, for now, let's pass nothing. */ _delegateDeserializer = findDeserializer(ctxt, delegateType, null); } if (_valueInstantiator.canCreateFromObjectWith()) { SettableBeanProperty[] creatorProps = _valueInstantiator.getFromObjectArguments(ctxt.getConfig()); _propertyBasedCreator = PropertyBasedCreator.construct(ctxt, _valueInstantiator, creatorProps); } _standardStringKey = _isStdKeyDeser(_mapType, _keyDeserializer); } /** * Method called to finalize setup of this deserializer, * when it is known for which property deserializer is needed for. */ @Override public JsonDeserializer createContextual(DeserializationContext ctxt, BeanProperty property) throws JsonMappingException { KeyDeserializer kd = _keyDeserializer; if (kd == null) { kd = ctxt.findKeyDeserializer(_mapType.getKeyType(), property); } else { if (kd instanceof ContextualKeyDeserializer) { kd = ((ContextualKeyDeserializer) kd).createContextual(ctxt, property); } } JsonDeserializer vd = _valueDeserializer; // #125: May have a content converter vd = findConvertingContentDeserializer(ctxt, property, vd); if (vd == null) { vd = ctxt.findContextualValueDeserializer(_mapType.getContentType(), property); } else { // if directly assigned, probably not yet contextual, so: vd = ctxt.handleSecondaryContextualization(vd, property); } TypeDeserializer vtd = _valueTypeDeserializer; if (vtd != null) { vtd = vtd.forProperty(property); } HashSet ignored = _ignorableProperties; AnnotationIntrospector intr = ctxt.getAnnotationIntrospector(); if (intr != null && property != null) { String[] moreToIgnore = intr.findPropertiesToIgnore(property.getMember()); if (moreToIgnore != null) { ignored = (ignored == null) ? new HashSet() : new HashSet(ignored); for (String str : moreToIgnore) { ignored.add(str); } } } return withResolved(kd, vtd, vd, ignored); } /* /********************************************************** /* ContainerDeserializerBase API /********************************************************** */ @Override public JavaType getContentType() { return _mapType.getContentType(); } @Override public JsonDeserializer getContentDeserializer() { return _valueDeserializer; } /* /********************************************************** /* JsonDeserializer API /********************************************************** */ /** * Turns out that these are expensive enough to create so that caching * does make sense. *

* IMPORTANT: but, note, that instances CAN NOT BE CACHED if there is * a value type deserializer; this caused an issue with 2.4.4 of * JAXB Annotations (failing a test). * It is also possible that some other settings could make deserializers * un-cacheable; but on the other hand, caching can make a big positive * difference with performance... so it's a hard choice. * * @since 2.4.4 */ @Override public boolean isCachable() { return (_valueTypeDeserializer == null) && (_ignorableProperties == null); } @Override @SuppressWarnings("unchecked") public Map deserialize(JsonParser jp, DeserializationContext ctxt) throws IOException, JsonProcessingException { if (_propertyBasedCreator != null) { return _deserializeUsingCreator(jp, ctxt); } if (_delegateDeserializer != null) { return (Map) _valueInstantiator.createUsingDelegate(ctxt, _delegateDeserializer.deserialize(jp, ctxt)); } if (!_hasDefaultCreator) { throw ctxt.instantiationException(getMapClass(), "No default constructor found"); } // Ok: must point to START_OBJECT, FIELD_NAME or END_OBJECT JsonToken t = jp.getCurrentToken(); if (t != JsonToken.START_OBJECT && t != JsonToken.FIELD_NAME && t != JsonToken.END_OBJECT) { // [JACKSON-620] (empty) String may be ok however: if (t == JsonToken.VALUE_STRING) { return (Map) _valueInstantiator.createFromString(ctxt, jp.getText()); } throw ctxt.mappingException(getMapClass()); } final Map result = (Map) _valueInstantiator.createUsingDefault(ctxt); if (_standardStringKey) { _readAndBindStringMap(jp, ctxt, result); return result; } _readAndBind(jp, ctxt, result); return result; } @Override public Map deserialize(JsonParser jp, DeserializationContext ctxt, Map result) throws IOException, JsonProcessingException { // Ok: must point to START_OBJECT or FIELD_NAME JsonToken t = jp.getCurrentToken(); if (t != JsonToken.START_OBJECT && t != JsonToken.FIELD_NAME) { throw ctxt.mappingException(getMapClass()); } if (_standardStringKey) { _readAndBindStringMap(jp, ctxt, result); return result; } _readAndBind(jp, ctxt, result); return result; } @Override public Object deserializeWithType(JsonParser jp, DeserializationContext ctxt, TypeDeserializer typeDeserializer) throws IOException, JsonProcessingException { // In future could check current token... for now this should be enough: return typeDeserializer.deserializeTypedFromObject(jp, ctxt); } /* /********************************************************** /* Other public accessors /********************************************************** */ @SuppressWarnings("unchecked") public final Class getMapClass() { return (Class>) _mapType.getRawClass(); } @Override public JavaType getValueType() { return _mapType; } /* /********************************************************** /* Internal methods /********************************************************** */ protected final void _readAndBind(JsonParser jp, DeserializationContext ctxt, Map result) throws IOException, JsonProcessingException { JsonToken t = jp.getCurrentToken(); if (t == JsonToken.START_OBJECT) { t = jp.nextToken(); } final KeyDeserializer keyDes = _keyDeserializer; final JsonDeserializer valueDes = _valueDeserializer; final TypeDeserializer typeDeser = _valueTypeDeserializer; MapReferringAccumulator referringAccumulator = null; boolean useObjectId = valueDes.getObjectIdReader() != null; if (useObjectId) { referringAccumulator = new MapReferringAccumulator(_mapType.getContentType().getRawClass(), result); } for (; t == JsonToken.FIELD_NAME; t = jp.nextToken()) { // Must point to field name String fieldName = jp.getCurrentName(); Object key = keyDes.deserializeKey(fieldName, ctxt); // And then the value... t = jp.nextToken(); if (_ignorableProperties != null && _ignorableProperties.contains(fieldName)) { jp.skipChildren(); continue; } try{ // Note: must handle null explicitly here; value deserializers won't Object value; if (t == JsonToken.VALUE_NULL) { value = valueDes.getNullValue(); } else if (typeDeser == null) { value = valueDes.deserialize(jp, ctxt); } else { value = valueDes.deserializeWithType(jp, ctxt, typeDeser); } /* !!! 23-Dec-2008, tatu: should there be an option to verify * that there are no duplicate field names? (and/or what * to do, keep-first or keep-last) */ if (useObjectId) { referringAccumulator.put(key, value); } else { result.put(key, value); } } catch (UnresolvedForwardReference reference) { handleUnresolvedReference(jp, referringAccumulator, key, reference); } catch (Exception e) { wrapAndThrow(e, result, fieldName); } } } /** * Optimized method used when keys can be deserialized as plain old * {@link java.lang.String}s, and there is no custom deserialized * specified. */ protected final void _readAndBindStringMap(JsonParser jp, DeserializationContext ctxt, Map result) throws IOException, JsonProcessingException { JsonToken t = jp.getCurrentToken(); if (t == JsonToken.START_OBJECT) { t = jp.nextToken(); } final JsonDeserializer valueDes = _valueDeserializer; final TypeDeserializer typeDeser = _valueTypeDeserializer; MapReferringAccumulator referringAccumulator = null; boolean useObjectId = valueDes.getObjectIdReader() != null; if (useObjectId) { referringAccumulator = new MapReferringAccumulator(_mapType.getContentType().getRawClass(), result); } for (; t == JsonToken.FIELD_NAME; t = jp.nextToken()) { // Must point to field name String fieldName = jp.getCurrentName(); // And then the value... t = jp.nextToken(); if (_ignorableProperties != null && _ignorableProperties.contains(fieldName)) { jp.skipChildren(); continue; } try { // Note: must handle null explicitly here; value deserializers won't Object value; if (t == JsonToken.VALUE_NULL) { value = valueDes.getNullValue(); } else if (typeDeser == null) { value = valueDes.deserialize(jp, ctxt); } else { value = valueDes.deserializeWithType(jp, ctxt, typeDeser); } if (useObjectId) { referringAccumulator.put(fieldName, value); } else { result.put(fieldName, value); } } catch (UnresolvedForwardReference reference) { handleUnresolvedReference(jp, referringAccumulator, fieldName, reference); } catch (Exception e) { wrapAndThrow(e, result, fieldName); } } } @SuppressWarnings("unchecked") public Map _deserializeUsingCreator(JsonParser jp, DeserializationContext ctxt) throws IOException, JsonProcessingException { final PropertyBasedCreator creator = _propertyBasedCreator; // null -> no ObjectIdReader for Maps (yet?) PropertyValueBuffer buffer = creator.startBuilding(jp, ctxt, null); JsonToken t = jp.getCurrentToken(); if (t == JsonToken.START_OBJECT) { t = jp.nextToken(); } final JsonDeserializer valueDes = _valueDeserializer; final TypeDeserializer typeDeser = _valueTypeDeserializer; for (; t == JsonToken.FIELD_NAME; t = jp.nextToken()) { String propName = jp.getCurrentName(); t = jp.nextToken(); // to get to value if (_ignorableProperties != null && _ignorableProperties.contains(propName)) { jp.skipChildren(); // and skip it (in case of array/object) continue; } // creator property? SettableBeanProperty prop = creator.findCreatorProperty(propName); if (prop != null) { // Last property to set? Object value = prop.deserialize(jp, ctxt); if (buffer.assignParameter(prop.getCreatorIndex(), value)) { jp.nextToken(); Map result; try { result = (Map)creator.build(ctxt, buffer); } catch (Exception e) { wrapAndThrow(e, _mapType.getRawClass(), propName); return null; } _readAndBind(jp, ctxt, result); return result; } continue; } // other property? needs buffering String fieldName = jp.getCurrentName(); Object key = _keyDeserializer.deserializeKey(fieldName, ctxt); Object value; try { if (t == JsonToken.VALUE_NULL) { value = valueDes.getNullValue(); } else if (typeDeser == null) { value = valueDes.deserialize(jp, ctxt); } else { value = valueDes.deserializeWithType(jp, ctxt, typeDeser); } } catch (Exception e) { wrapAndThrow(e, _mapType.getRawClass(), propName); return null; } buffer.bufferMapProperty(key, value); } // end of JSON object? // if so, can just construct and leave... try { return (Map)creator.build(ctxt, buffer); } catch (Exception e) { wrapAndThrow(e, _mapType.getRawClass(), null); return null; } } @Deprecated // since 2.5 protected void wrapAndThrow(Throwable t, Object ref) throws IOException { wrapAndThrow(t, ref, null); } // note: copied from BeanDeserializer; should try to share somehow... protected void wrapAndThrow(Throwable t, Object ref, String key) throws IOException { // to handle StackOverflow: while (t instanceof InvocationTargetException && t.getCause() != null) { t = t.getCause(); } // Errors and "plain" IOExceptions to be passed as is if (t instanceof Error) { throw (Error) t; } // ... except for mapping exceptions if (t instanceof IOException && !(t instanceof JsonMappingException)) { throw (IOException) t; } throw JsonMappingException.wrapWithPath(t, ref, key); } private void handleUnresolvedReference(JsonParser jp, MapReferringAccumulator accumulator, Object key, UnresolvedForwardReference reference) throws JsonMappingException { if (accumulator == null) { throw JsonMappingException.from(jp, "Unresolved forward reference but no identity info.", reference); } Referring referring = accumulator.handleUnresolvedReference(reference, key); reference.getRoid().appendReferring(referring); } private final static class MapReferringAccumulator { private final Class _valueType; private Map _result; /** * A list of {@link MapReferring} to maintain ordering. */ private List _accumulator = new ArrayList(); public MapReferringAccumulator(Class valueType, Map result) { _valueType = valueType; _result = result; } public void put(Object key, Object value) { if (_accumulator.isEmpty()) { _result.put(key, value); } else { MapReferring ref = _accumulator.get(_accumulator.size() - 1); ref.next.put(key, value); } } public Referring handleUnresolvedReference(UnresolvedForwardReference reference, Object key) { MapReferring id = new MapReferring(this, reference, _valueType, key); _accumulator.add(id); return id; } public void resolveForwardReference(Object id, Object value) throws IOException { Iterator iterator = _accumulator.iterator(); // Resolve ordering after resolution of an id. This means either: // 1- adding to the result map in case of the first unresolved id. // 2- merge the content of the resolved id with its previous unresolved id. Map previous = _result; while (iterator.hasNext()) { MapReferring ref = iterator.next(); if (ref.hasId(id)) { iterator.remove(); previous.put(ref.key, value); previous.putAll(ref.next); return; } previous = ref.next; } throw new IllegalArgumentException("Trying to resolve a forward reference with id [" + id + "] that wasn't previously seen as unresolved."); } } /** * Helper class to maintain processing order of value. The resolved * object associated with {@link #_id} comes before the values in * {@link _next}. */ private final static class MapReferring extends Referring { private final MapReferringAccumulator _parent; public final Map next = new LinkedHashMap(); public final Object key; protected MapReferring(MapReferringAccumulator parent, UnresolvedForwardReference ref, Class valueType, Object key) { super(ref, valueType); _parent = parent; this.key = key; } @Override public void handleResolvedForwardReference(Object id, Object value) throws IOException { _parent.resolveForwardReference(id, value); } } }