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

import java.io.IOException;

import com.fasterxml.jackson.core.*;

import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.databind.deser.BeanDeserializer;
import com.fasterxml.jackson.databind.deser.SettableBeanProperty;
import com.fasterxml.jackson.databind.util.NameTransformer;

Deserializer that builds on basic BeanDeserializer but override some aspects like instance construction.
/** * Deserializer that builds on basic {@link BeanDeserializer} but * override some aspects like instance construction. */
public class ThrowableDeserializer extends BeanDeserializer { private static final long serialVersionUID = 1L; protected final static String PROP_NAME_MESSAGE = "message"; /* /************************************************************ /* Construction /************************************************************ */ public ThrowableDeserializer(BeanDeserializer baseDeserializer) { super(baseDeserializer); // need to disable this, since we do post-processing _vanillaProcessing = false; }
Alternative constructor used when creating "unwrapping" deserializers
/** * Alternative constructor used when creating "unwrapping" deserializers */
protected ThrowableDeserializer(BeanDeserializer src, NameTransformer unwrapper) { super(src, unwrapper); } @Override public JsonDeserializer<Object> unwrappingDeserializer(NameTransformer unwrapper) { if (getClass() != ThrowableDeserializer.class) { return this; } /* main thing really is to just enforce ignoring of unknown * properties; since there may be multiple unwrapped values * and properties for all may be interleaved... */ return new ThrowableDeserializer(this, unwrapper); } /* /************************************************************ /* Overridden methods /************************************************************ */ @Override public Object deserializeFromObject(JsonParser p, DeserializationContext ctxt) throws IOException { // 30-Sep-2010, tatu: Need to allow use of @JsonCreator, so: if (_propertyBasedCreator != null) { // proper @JsonCreator return _deserializeUsingPropertyBased(p, ctxt); } if (_delegateDeserializer != null) { return _valueInstantiator.createUsingDelegate(ctxt, _delegateDeserializer.deserialize(p, ctxt)); } if (_beanType.isAbstract()) { // for good measure, check this too return ctxt.handleMissingInstantiator(handledType(), getValueInstantiator(), p, "abstract type (need to add/enable type information?)"); } boolean hasStringCreator = _valueInstantiator.canCreateFromString(); boolean hasDefaultCtor = _valueInstantiator.canCreateUsingDefault(); // and finally, verify we do have single-String arg constructor (if no @JsonCreator) if (!hasStringCreator && !hasDefaultCtor) { return ctxt.handleMissingInstantiator(handledType(), getValueInstantiator(), p, "Throwable needs a default constructor, a single-String-arg constructor; or explicit @JsonCreator"); } Object throwable = null; Object[] pending = null; int pendingIx = 0; for (; !p.hasToken(JsonToken.END_OBJECT); p.nextToken()) { String propName = p.getCurrentName(); SettableBeanProperty prop = _beanProperties.find(propName); p.nextToken(); // to point to field value if (prop != null) { // normal case if (throwable != null) { prop.deserializeAndSet(p, ctxt, throwable); continue; } // nope; need to defer if (pending == null) { int len = _beanProperties.size(); pending = new Object[len + len]; } pending[pendingIx++] = prop; pending[pendingIx++] = prop.deserialize(p, ctxt); continue; } // Maybe it's "message"? final boolean isMessage = PROP_NAME_MESSAGE.equals(propName); if (isMessage) { if (hasStringCreator) { throwable = _valueInstantiator.createFromString(ctxt, p.getValueAsString()); // any pending values? if (pending != null) { for (int i = 0, len = pendingIx; i < len; i += 2) { prop = (SettableBeanProperty)pending[i]; prop.set(throwable, pending[i+1]); } pending = null; } continue; } } // Things marked as ignorable should not be passed to any setter if ((_ignorableProps != null) && _ignorableProps.contains(propName)) { p.skipChildren(); continue; } if (_anySetter != null) { _anySetter.deserializeAndSet(p, ctxt, throwable, propName); continue; } // 23-Jan-2018, tatu: One concern would be `message`, but without any-setter or single-String-ctor // (or explicit constructor). We could just ignore it but for now, let it fail // Unknown: let's call handler method handleUnknownProperty(p, ctxt, throwable, propName); } // Sanity check: did we find "message"? if (throwable == null) { /* 15-Oct-2010, tatu: Can't assume missing message is an error, since it may be * suppressed during serialization, as per [JACKSON-388]. * * Should probably allow use of default constructor, too... */ //throw new JsonMappingException("No 'message' property found: could not deserialize "+_beanType); if (hasStringCreator) { throwable = _valueInstantiator.createFromString(ctxt, null); } else { throwable = _valueInstantiator.createUsingDefault(ctxt); } // any pending values? if (pending != null) { for (int i = 0, len = pendingIx; i < len; i += 2) { SettableBeanProperty prop = (SettableBeanProperty)pending[i]; prop.set(throwable, pending[i+1]); } } } return throwable; } }