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

import java.io.IOException;
import java.util.*;
import java.util.Objects;

import com.fasterxml.jackson.annotation.JsonFormat;

import com.fasterxml.jackson.core.*;
import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.databind.deser.ContextualDeserializer;
import com.fasterxml.jackson.databind.deser.NullValueProvider;
import com.fasterxml.jackson.databind.deser.impl.NullsConstantProvider;
import com.fasterxml.jackson.databind.jsontype.TypeDeserializer;
import com.fasterxml.jackson.databind.type.LogicalType;
import com.fasterxml.jackson.databind.util.AccessPattern;

Standard deserializer for EnumSets.

Note: casting within this class is all messed up -- just could not figure out a way to properly deal with recursive definition of "EnumSet<K extends Enum<K>, V>

/** * Standard deserializer for {@link EnumSet}s. * <p> * Note: casting within this class is all messed up -- just could not figure out a way * to properly deal with recursive definition of "EnumSet&lt;K extends Enum&lt;K&gt;, V&gt; */
@SuppressWarnings("rawtypes") public class EnumSetDeserializer extends StdDeserializer<EnumSet<?>> implements ContextualDeserializer { private static final long serialVersionUID = 1L; // since 2.5 protected final JavaType _enumType; protected JsonDeserializer<Enum<?>> _enumDeserializer;
Handler we need for dealing with nulls.
Since:2.10.1
/** * Handler we need for dealing with nulls. * * @since 2.10.1 */
protected final NullValueProvider _nullProvider;
Marker flag set if the _nullProvider indicates that all null content values should be skipped (instead of being possibly converted).
Since:2.10.1
/** * Marker flag set if the <code>_nullProvider</code> indicates that all null * content values should be skipped (instead of being possibly converted). * * @since 2.10.1 */
protected final boolean _skipNullValues;
Specific override for this instance (from proper, or global per-type overrides) to indicate whether single value may be taken to mean an unwrapped one-element array or not. If null, left to global defaults.
Since:2.7
/** * Specific override for this instance (from proper, or global per-type overrides) * to indicate whether single value may be taken to mean an unwrapped one-element array * or not. If null, left to global defaults. * * @since 2.7 */
protected final Boolean _unwrapSingle; /* /********************************************************** /* Life-cycle /********************************************************** */ @SuppressWarnings("unchecked" ) public EnumSetDeserializer(JavaType enumType, JsonDeserializer<?> deser) { super(EnumSet.class); _enumType = enumType; // sanity check if (!enumType.isEnumType()) { throw new IllegalArgumentException("Type "+enumType+" not Java Enum type"); } _enumDeserializer = (JsonDeserializer<Enum<?>>) deser; _unwrapSingle = null; _nullProvider = null; _skipNullValues = false; }
Since:2.7
Deprecated:Since 2.10.1
/** * @since 2.7 * @deprecated Since 2.10.1 */
@Deprecated protected EnumSetDeserializer(EnumSetDeserializer base, JsonDeserializer<?> deser, Boolean unwrapSingle) { this(base, deser, base._nullProvider, unwrapSingle); }
Since:2.10.1
/** * @since 2.10.1 */
@SuppressWarnings("unchecked" ) protected EnumSetDeserializer(EnumSetDeserializer base, JsonDeserializer<?> deser, NullValueProvider nuller, Boolean unwrapSingle) { super(base); _enumType = base._enumType; _enumDeserializer = (JsonDeserializer<Enum<?>>) deser; _nullProvider = nuller; _skipNullValues = NullsConstantProvider.isSkipper(nuller); _unwrapSingle = unwrapSingle; } public EnumSetDeserializer withDeserializer(JsonDeserializer<?> deser) { if (_enumDeserializer == deser) { return this; } return new EnumSetDeserializer(this, deser, _nullProvider, _unwrapSingle); } @Deprecated // since 2.10.1 public EnumSetDeserializer withResolved(JsonDeserializer<?> deser, Boolean unwrapSingle) { return withResolved(deser, _nullProvider, unwrapSingle); }
Since:2.10.1
/** * @since 2.10.1 */
public EnumSetDeserializer withResolved(JsonDeserializer<?> deser, NullValueProvider nuller, Boolean unwrapSingle) { if ((Objects.equals(_unwrapSingle, unwrapSingle)) && (_enumDeserializer == deser) && (_nullProvider == deser)) { return this; } return new EnumSetDeserializer(this, deser, nuller, unwrapSingle); } /* /********************************************************** /* Basic metadata /********************************************************** */
Because of costs associated with constructing Enum resolvers, let's cache instances by default.
/** * Because of costs associated with constructing Enum resolvers, * let's cache instances by default. */
@Override public boolean isCachable() { // One caveat: content deserializer should prevent caching if (_enumType.getValueHandler() != null) { return false; } return true; } @Override // since 2.12 public LogicalType logicalType() { return LogicalType.Collection; } @Override // since 2.9 public Boolean supportsUpdate(DeserializationConfig config) { return Boolean.TRUE; } @Override // since 2.10.1 public Object getEmptyValue(DeserializationContext ctxt) throws JsonMappingException { return constructSet(); } @Override // since 2.10.1 public AccessPattern getEmptyAccessPattern() { return AccessPattern.DYNAMIC; } /* /********************************************************** /* Contextualization /********************************************************** */ @Override public JsonDeserializer<?> createContextual(DeserializationContext ctxt, BeanProperty property) throws JsonMappingException { // 07-May-2020, tatu: Is the argument `EnumSet.class` correct here? // In a way seems like it should rather refer to value class... ? // (as it's individual value of element type, not Container)... final Boolean unwrapSingle = findFormatFeature(ctxt, property, EnumSet.class, JsonFormat.Feature.ACCEPT_SINGLE_VALUE_AS_ARRAY); JsonDeserializer<?> deser = _enumDeserializer; if (deser == null) { deser = ctxt.findContextualValueDeserializer(_enumType, property); } else { // if directly assigned, probably not yet contextual, so: deser = ctxt.handleSecondaryContextualization(deser, property, _enumType); } return withResolved(deser, findContentNullProvider(ctxt, property, deser), unwrapSingle); } /* /********************************************************** /* JsonDeserializer API /********************************************************** */ @Override public EnumSet<?> deserialize(JsonParser p, DeserializationContext ctxt) throws IOException { EnumSet result = constructSet(); // Ok: must point to START_ARRAY (or equivalent) if (!p.isExpectedStartArrayToken()) { return handleNonArray(p, ctxt, result); } return _deserialize(p, ctxt, result); } @Override public EnumSet<?> deserialize(JsonParser p, DeserializationContext ctxt, EnumSet<?> result) throws IOException { // Ok: must point to START_ARRAY (or equivalent) if (!p.isExpectedStartArrayToken()) { return handleNonArray(p, ctxt, result); } return _deserialize(p, ctxt, result); } @SuppressWarnings("unchecked") protected final EnumSet<?> _deserialize(JsonParser p, DeserializationContext ctxt, EnumSet result) throws IOException { JsonToken t; try { while ((t = p.nextToken()) != JsonToken.END_ARRAY) { // What to do with nulls? Fail or ignore? Fail, for now (note: would fail if we // passed it to EnumDeserializer, too, but in general nulls should never be passed // to non-container deserializers) Enum<?> value; if (t == JsonToken.VALUE_NULL) { if (_skipNullValues) { continue; } value = (Enum<?>) _nullProvider.getNullValue(ctxt); } else { value = _enumDeserializer.deserialize(p, ctxt); } if (value != null) { result.add(value); } } } catch (Exception e) { throw JsonMappingException.wrapWithPath(e, result, result.size()); } return result; } @Override public Object deserializeWithType(JsonParser p, DeserializationContext ctxt, TypeDeserializer typeDeserializer) throws IOException { return typeDeserializer.deserializeTypedFromArray(p, ctxt); } @SuppressWarnings("unchecked") private EnumSet constructSet() { return EnumSet.noneOf((Class<Enum>) _enumType.getRawClass()); } @SuppressWarnings("unchecked") protected EnumSet<?> handleNonArray(JsonParser p, DeserializationContext ctxt, EnumSet result) throws IOException { boolean canWrap = (_unwrapSingle == Boolean.TRUE) || ((_unwrapSingle == null) && ctxt.isEnabled(DeserializationFeature.ACCEPT_SINGLE_VALUE_AS_ARRAY)); if (!canWrap) { return (EnumSet<?>) ctxt.handleUnexpectedToken(EnumSet.class, p); } // First: since `null`s not allowed, slightly simpler... if (p.hasToken(JsonToken.VALUE_NULL)) { return (EnumSet<?>) ctxt.handleUnexpectedToken(_enumType, p); } try { Enum<?> value = _enumDeserializer.deserialize(p, ctxt); if (value != null) { result.add(value); } } catch (Exception e) { throw JsonMappingException.wrapWithPath(e, result, result.size()); } return result; } }