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com.fasterxml.jackson.databind.deser.BeanDeserializer Maven / Gradle / Ivy
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package com.fasterxml.jackson.databind.deser;
import java.io.IOException;
import java.util.*;
import com.fasterxml.jackson.core.*;
import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.databind.deser.impl.*;
import com.fasterxml.jackson.databind.util.NameTransformer;
import com.fasterxml.jackson.databind.util.TokenBuffer;
/**
* Deserializer class that can deserialize instances of
* arbitrary bean objects, usually from JSON Object structs,
* but possibly also from simple types like String values.
*/
public class BeanDeserializer
extends BeanDeserializerBase
implements java.io.Serializable
{
private static final long serialVersionUID = 1L;
/*
/**********************************************************
/* Life-cycle, construction, initialization
/**********************************************************
*/
/**
* Constructor used by {@link BeanDeserializerBuilder}.
*/
public BeanDeserializer(BeanDeserializerBuilder builder,
BeanDescription beanDesc,
BeanPropertyMap properties, Map backRefs,
HashSet ignorableProps, boolean ignoreAllUnknown,
boolean hasViews)
{
super(builder, beanDesc, properties, backRefs,
ignorableProps, ignoreAllUnknown, hasViews);
}
/**
* Copy-constructor that can be used by sub-classes to allow
* copy-on-write style copying of settings of an existing instance.
*/
protected BeanDeserializer(BeanDeserializerBase src) {
super(src, src._ignoreAllUnknown);
}
protected BeanDeserializer(BeanDeserializerBase src, boolean ignoreAllUnknown) {
super(src, ignoreAllUnknown);
}
protected BeanDeserializer(BeanDeserializerBase src, NameTransformer unwrapper) {
super(src, unwrapper);
}
public BeanDeserializer(BeanDeserializerBase src, ObjectIdReader oir) {
super(src, oir);
}
public BeanDeserializer(BeanDeserializerBase src, HashSet ignorableProps) {
super(src, ignorableProps);
}
@Override
public JsonDeserializer unwrappingDeserializer(NameTransformer unwrapper)
{
/* bit kludgy but we don't want to accidentally change type; sub-classes
* MUST override this method to support unwrapped properties...
*/
if (getClass() != BeanDeserializer.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 BeanDeserializer(this, unwrapper);
}
@Override
public BeanDeserializer withObjectIdReader(ObjectIdReader oir) {
return new BeanDeserializer(this, oir);
}
@Override
public BeanDeserializer withIgnorableProperties(HashSet ignorableProps) {
return new BeanDeserializer(this, ignorableProps);
}
@Override
protected BeanDeserializerBase asArrayDeserializer() {
SettableBeanProperty[] props = _beanProperties.getPropertiesInInsertionOrder();
return new BeanAsArrayDeserializer(this, props);
}
/*
/**********************************************************
/* JsonDeserializer implementation
/**********************************************************
*/
/**
* Main deserialization method for bean-based objects (POJOs).
*
* NOTE: was declared 'final' in 2.2; should NOT be to let extensions
* like Afterburner change definition.
*/
@Override
public Object deserialize(JsonParser jp, DeserializationContext ctxt)
throws IOException, JsonProcessingException
{
JsonToken t = jp.getCurrentToken();
// common case first:
if (t == JsonToken.START_OBJECT) {
if (_vanillaProcessing) {
return vanillaDeserialize(jp, ctxt, jp.nextToken());
}
jp.nextToken();
if (_objectIdReader != null) {
return deserializeWithObjectId(jp, ctxt);
}
return deserializeFromObject(jp, ctxt);
}
return _deserializeOther(jp, ctxt, t);
}
protected final Object _deserializeOther(JsonParser jp, DeserializationContext ctxt,
JsonToken t)
throws IOException, JsonProcessingException
{
if (t == null) {
return _missingToken(jp, ctxt);
}
// and then others, generally requiring use of @JsonCreator
switch (t) {
case VALUE_STRING:
return deserializeFromString(jp, ctxt);
case VALUE_NUMBER_INT:
return deserializeFromNumber(jp, ctxt);
case VALUE_NUMBER_FLOAT:
return deserializeFromDouble(jp, ctxt);
case VALUE_EMBEDDED_OBJECT:
return jp.getEmbeddedObject();
case VALUE_TRUE:
case VALUE_FALSE:
return deserializeFromBoolean(jp, ctxt);
case START_ARRAY:
// these only work if there's a (delegating) creator...
return deserializeFromArray(jp, ctxt);
case FIELD_NAME:
case END_OBJECT: // added to resolve [JACKSON-319], possible related issues
if (_vanillaProcessing) {
return vanillaDeserialize(jp, ctxt, t);
}
if (_objectIdReader != null) {
return deserializeWithObjectId(jp, ctxt);
}
return deserializeFromObject(jp, ctxt);
default:
throw ctxt.mappingException(handledType());
}
}
protected Object _missingToken(JsonParser jp, DeserializationContext ctxt)
throws JsonProcessingException
{
throw ctxt.endOfInputException(handledType());
}
/**
* Secondary deserialization method, called in cases where POJO
* instance is created as part of deserialization, potentially
* after collecting some or all of the properties to set.
*/
@Override
public Object deserialize(JsonParser jp, DeserializationContext ctxt, Object bean)
throws IOException, JsonProcessingException
{
if (_injectables != null) {
injectValues(ctxt, bean);
}
if (_unwrappedPropertyHandler != null) {
return deserializeWithUnwrapped(jp, ctxt, bean);
}
if (_externalTypeIdHandler != null) {
return deserializeWithExternalTypeId(jp, ctxt, bean);
}
JsonToken t = jp.getCurrentToken();
// 23-Mar-2010, tatu: In some cases, we start with full JSON object too...
if (t == JsonToken.START_OBJECT) {
t = jp.nextToken();
}
if (_needViewProcesing) {
Class> view = ctxt.getActiveView();
if (view != null) {
return deserializeWithView(jp, ctxt, bean, view);
}
}
for (; t == JsonToken.FIELD_NAME; t = jp.nextToken()) {
String propName = jp.getCurrentName();
// Skip field name:
jp.nextToken();
SettableBeanProperty prop = _beanProperties.find(propName);
if (prop != null) { // normal case
try {
prop.deserializeAndSet(jp, ctxt, bean);
} catch (Exception e) {
wrapAndThrow(e, bean, propName, ctxt);
}
continue;
}
handleUnknownVanilla(jp, ctxt, bean, propName);
}
return bean;
}
/*
/**********************************************************
/* Concrete deserialization methods
/**********************************************************
*/
/**
* Streamlined version that is only used when no "special"
* features are enabled.
*/
private final Object vanillaDeserialize(JsonParser jp,
DeserializationContext ctxt, JsonToken t)
throws IOException, JsonProcessingException
{
final Object bean = _valueInstantiator.createUsingDefault(ctxt);
for (; jp.getCurrentToken() != JsonToken.END_OBJECT; jp.nextToken()) {
String propName = jp.getCurrentName();
// Skip field name:
jp.nextToken();
SettableBeanProperty prop = _beanProperties.find(propName);
if (prop != null) { // normal case
try {
prop.deserializeAndSet(jp, ctxt, bean);
} catch (Exception e) {
wrapAndThrow(e, bean, propName, ctxt);
}
} else {
handleUnknownVanilla(jp, ctxt, bean, propName);
}
}
return bean;
}
/**
* General version used when handling needs more advanced
* features.
*/
@Override
public Object deserializeFromObject(JsonParser jp, DeserializationContext ctxt)
throws IOException, JsonProcessingException
{
if (_nonStandardCreation) {
if (_unwrappedPropertyHandler != null) {
return deserializeWithUnwrapped(jp, ctxt);
}
if (_externalTypeIdHandler != null) {
return deserializeWithExternalTypeId(jp, ctxt);
}
return deserializeFromObjectUsingNonDefault(jp, ctxt);
}
final Object bean = _valueInstantiator.createUsingDefault(ctxt);
if (jp.canReadObjectId()) {
Object id = jp.getObjectId();
if (id != null) {
_handleTypedObjectId(jp, ctxt, bean, id);
}
}
if (_injectables != null) {
injectValues(ctxt, bean);
}
if (_needViewProcesing) {
Class> view = ctxt.getActiveView();
if (view != null) {
return deserializeWithView(jp, ctxt, bean, view);
}
}
for (; jp.getCurrentToken() != JsonToken.END_OBJECT; jp.nextToken()) {
String propName = jp.getCurrentName();
// Skip field name:
jp.nextToken();
SettableBeanProperty prop = _beanProperties.find(propName);
if (prop != null) { // normal case
try {
prop.deserializeAndSet(jp, ctxt, bean);
} catch (Exception e) {
wrapAndThrow(e, bean, propName, ctxt);
}
continue;
}
handleUnknownVanilla(jp, ctxt, bean, propName);
}
return bean;
}
/**
* Method called to deserialize bean using "property-based creator":
* this means that a non-default constructor or factory method is
* called, and then possibly other setters. The trick is that
* values for creator method need to be buffered, first; and
* due to non-guaranteed ordering possibly some other properties
* as well.
*/
@Override
@SuppressWarnings("resource")
protected Object _deserializeUsingPropertyBased(final JsonParser jp, final DeserializationContext ctxt)
throws IOException, JsonProcessingException
{
final PropertyBasedCreator creator = _propertyBasedCreator;
PropertyValueBuffer buffer = creator.startBuilding(jp, ctxt, _objectIdReader);
// 04-Jan-2010, tatu: May need to collect unknown properties for polymorphic cases
TokenBuffer unknown = null;
JsonToken t = jp.getCurrentToken();
for (; t == JsonToken.FIELD_NAME; t = jp.nextToken()) {
String propName = jp.getCurrentName();
jp.nextToken(); // to point to value
// creator property?
SettableBeanProperty creatorProp = creator.findCreatorProperty(propName);
if (creatorProp != null) {
// Last creator property to set?
Object value = creatorProp.deserialize(jp, ctxt);
if (buffer.assignParameter(creatorProp.getCreatorIndex(), value)) {
jp.nextToken(); // to move to following FIELD_NAME/END_OBJECT
Object bean;
try {
bean = creator.build(ctxt, buffer);
} catch (Exception e) {
wrapAndThrow(e, _beanType.getRawClass(), propName, ctxt);
bean = null; // never gets here
}
// polymorphic?
if (bean.getClass() != _beanType.getRawClass()) {
return handlePolymorphic(jp, ctxt, bean, unknown);
}
if (unknown != null) { // nope, just extra unknown stuff...
bean = handleUnknownProperties(ctxt, bean, unknown);
}
// or just clean?
return deserialize(jp, ctxt, bean);
}
continue;
}
// Object Id property?
if (buffer.readIdProperty(propName)) {
continue;
}
// regular property? needs buffering
SettableBeanProperty prop = _beanProperties.find(propName);
if (prop != null) {
buffer.bufferProperty(prop, prop.deserialize(jp, ctxt));
continue;
}
// As per [JACKSON-313], things marked as ignorable should not be
// passed to any setter
if (_ignorableProps != null && _ignorableProps.contains(propName)) {
handleIgnoredProperty(jp, ctxt, handledType(), propName);
continue;
}
// "any property"?
if (_anySetter != null) {
buffer.bufferAnyProperty(_anySetter, propName, _anySetter.deserialize(jp, ctxt));
continue;
}
// Ok then, let's collect the whole field; name and value
if (unknown == null) {
unknown = new TokenBuffer(jp);
}
unknown.writeFieldName(propName);
unknown.copyCurrentStructure(jp);
}
// We hit END_OBJECT, so:
Object bean;
try {
bean = creator.build(ctxt, buffer);
} catch (Exception e) {
wrapInstantiationProblem(e, ctxt);
bean = null; // never gets here
}
if (unknown != null) {
// polymorphic?
if (bean.getClass() != _beanType.getRawClass()) {
return handlePolymorphic(null, ctxt, bean, unknown);
}
// no, just some extra unknown properties
return handleUnknownProperties(ctxt, bean, unknown);
}
return bean;
}
/*
/**********************************************************
/* Deserializing when we have to consider an active View
/**********************************************************
*/
protected final Object deserializeWithView(JsonParser jp, DeserializationContext ctxt,
Object bean, Class> activeView)
throws IOException, JsonProcessingException
{
JsonToken t = jp.getCurrentToken();
for (; t == JsonToken.FIELD_NAME; t = jp.nextToken()) {
String propName = jp.getCurrentName();
// Skip field name:
jp.nextToken();
SettableBeanProperty prop = _beanProperties.find(propName);
if (prop != null) {
if (!prop.visibleInView(activeView)) {
jp.skipChildren();
continue;
}
try {
prop.deserializeAndSet(jp, ctxt, bean);
} catch (Exception e) {
wrapAndThrow(e, bean, propName, ctxt);
}
continue;
}
handleUnknownVanilla(jp, ctxt, bean, propName);
}
return bean;
}
/*
/**********************************************************
/* Handling for cases where we have "unwrapped" values
/**********************************************************
*/
/**
* Method called when there are declared "unwrapped" properties
* which need special handling
*/
@SuppressWarnings("resource")
protected Object deserializeWithUnwrapped(JsonParser jp, DeserializationContext ctxt)
throws IOException, JsonProcessingException
{
if (_delegateDeserializer != null) {
return _valueInstantiator.createUsingDelegate(ctxt, _delegateDeserializer.deserialize(jp, ctxt));
}
if (_propertyBasedCreator != null) {
return deserializeUsingPropertyBasedWithUnwrapped(jp, ctxt);
}
TokenBuffer tokens = new TokenBuffer(jp);
tokens.writeStartObject();
final Object bean = _valueInstantiator.createUsingDefault(ctxt);
if (_injectables != null) {
injectValues(ctxt, bean);
}
final Class> activeView = _needViewProcesing ? ctxt.getActiveView() : null;
for (; jp.getCurrentToken() != JsonToken.END_OBJECT; jp.nextToken()) {
String propName = jp.getCurrentName();
jp.nextToken();
SettableBeanProperty prop = _beanProperties.find(propName);
if (prop != null) { // normal case
if (activeView != null && !prop.visibleInView(activeView)) {
jp.skipChildren();
continue;
}
try {
prop.deserializeAndSet(jp, ctxt, bean);
} catch (Exception e) {
wrapAndThrow(e, bean, propName, ctxt);
}
continue;
}
// ignorable things should be ignored
if (_ignorableProps != null && _ignorableProps.contains(propName)) {
handleIgnoredProperty(jp, ctxt, bean, propName);
continue;
}
// but... others should be passed to unwrapped property deserializers
tokens.writeFieldName(propName);
tokens.copyCurrentStructure(jp);
// how about any setter? We'll get copies but...
if (_anySetter != null) {
try {
_anySetter.deserializeAndSet(jp, ctxt, bean, propName);
} catch (Exception e) {
wrapAndThrow(e, bean, propName, ctxt);
}
continue;
}
}
tokens.writeEndObject();
_unwrappedPropertyHandler.processUnwrapped(jp, ctxt, bean, tokens);
return bean;
}
@SuppressWarnings("resource")
protected Object deserializeWithUnwrapped(JsonParser jp, DeserializationContext ctxt, Object bean)
throws IOException, JsonProcessingException
{
JsonToken t = jp.getCurrentToken();
if (t == JsonToken.START_OBJECT) {
t = jp.nextToken();
}
TokenBuffer tokens = new TokenBuffer(jp);
tokens.writeStartObject();
final Class> activeView = _needViewProcesing ? ctxt.getActiveView() : null;
for (; t == JsonToken.FIELD_NAME; t = jp.nextToken()) {
String propName = jp.getCurrentName();
SettableBeanProperty prop = _beanProperties.find(propName);
jp.nextToken();
if (prop != null) { // normal case
if (activeView != null && !prop.visibleInView(activeView)) {
jp.skipChildren();
continue;
}
try {
prop.deserializeAndSet(jp, ctxt, bean);
} catch (Exception e) {
wrapAndThrow(e, bean, propName, ctxt);
}
continue;
}
if (_ignorableProps != null && _ignorableProps.contains(propName)) {
handleIgnoredProperty(jp, ctxt, bean, propName);
continue;
}
// but... others should be passed to unwrapped property deserializers
tokens.writeFieldName(propName);
tokens.copyCurrentStructure(jp);
// how about any setter? We'll get copies but...
if (_anySetter != null) {
_anySetter.deserializeAndSet(jp, ctxt, bean, propName);
}
}
tokens.writeEndObject();
_unwrappedPropertyHandler.processUnwrapped(jp, ctxt, bean, tokens);
return bean;
}
@SuppressWarnings("resource")
protected Object deserializeUsingPropertyBasedWithUnwrapped(JsonParser jp, DeserializationContext ctxt)
throws IOException, JsonProcessingException
{
final PropertyBasedCreator creator = _propertyBasedCreator;
PropertyValueBuffer buffer = creator.startBuilding(jp, ctxt, _objectIdReader);
TokenBuffer tokens = new TokenBuffer(jp);
tokens.writeStartObject();
JsonToken t = jp.getCurrentToken();
for (; t == JsonToken.FIELD_NAME; t = jp.nextToken()) {
String propName = jp.getCurrentName();
jp.nextToken(); // to point to value
// creator property?
SettableBeanProperty creatorProp = creator.findCreatorProperty(propName);
if (creatorProp != null) {
// Last creator property to set?
Object value = creatorProp.deserialize(jp, ctxt);
if (buffer.assignParameter(creatorProp.getCreatorIndex(), value)) {
t = jp.nextToken(); // to move to following FIELD_NAME/END_OBJECT
Object bean;
try {
bean = creator.build(ctxt, buffer);
} catch (Exception e) {
wrapAndThrow(e, _beanType.getRawClass(), propName, ctxt);
continue; // never gets here
}
// if so, need to copy all remaining tokens into buffer
while (t == JsonToken.FIELD_NAME) {
jp.nextToken(); // to skip name
tokens.copyCurrentStructure(jp);
t = jp.nextToken();
}
tokens.writeEndObject();
if (bean.getClass() != _beanType.getRawClass()) {
// !!! 08-Jul-2011, tatu: Could probably support; but for now
// it's too complicated, so bail out
tokens.close();
throw ctxt.mappingException("Can not create polymorphic instances with unwrapped values");
}
return _unwrappedPropertyHandler.processUnwrapped(jp, ctxt, bean, tokens);
}
continue;
}
// Object Id property?
if (buffer.readIdProperty(propName)) {
continue;
}
// regular property? needs buffering
SettableBeanProperty prop = _beanProperties.find(propName);
if (prop != null) {
buffer.bufferProperty(prop, prop.deserialize(jp, ctxt));
continue;
}
/* As per [JACKSON-313], things marked as ignorable should not be
* passed to any setter
*/
if (_ignorableProps != null && _ignorableProps.contains(propName)) {
handleIgnoredProperty(jp, ctxt, handledType(), propName);
continue;
}
tokens.writeFieldName(propName);
tokens.copyCurrentStructure(jp);
// "any property"?
if (_anySetter != null) {
buffer.bufferAnyProperty(_anySetter, propName, _anySetter.deserialize(jp, ctxt));
}
}
// We hit END_OBJECT, so:
Object bean;
try {
bean = creator.build(ctxt, buffer);
} catch (Exception e) {
wrapInstantiationProblem(e, ctxt);
return null; // never gets here
}
return _unwrappedPropertyHandler.processUnwrapped(jp, ctxt, bean, tokens);
}
/*
/**********************************************************
/* Handling for cases where we have property/-ies with
/* external type id
/**********************************************************
*/
protected Object deserializeWithExternalTypeId(JsonParser jp, DeserializationContext ctxt)
throws IOException, JsonProcessingException
{
if (_propertyBasedCreator != null) {
return deserializeUsingPropertyBasedWithExternalTypeId(jp, ctxt);
}
return deserializeWithExternalTypeId(jp, ctxt, _valueInstantiator.createUsingDefault(ctxt));
}
protected Object deserializeWithExternalTypeId(JsonParser jp, DeserializationContext ctxt,
Object bean)
throws IOException, JsonProcessingException
{
final Class> activeView = _needViewProcesing ? ctxt.getActiveView() : null;
final ExternalTypeHandler ext = _externalTypeIdHandler.start();
for (; jp.getCurrentToken() != JsonToken.END_OBJECT; jp.nextToken()) {
String propName = jp.getCurrentName();
jp.nextToken();
SettableBeanProperty prop = _beanProperties.find(propName);
if (prop != null) { // normal case
// [JACKSON-831]: may have property AND be used as external type id:
if (jp.getCurrentToken().isScalarValue()) {
ext.handleTypePropertyValue(jp, ctxt, propName, bean);
}
if (activeView != null && !prop.visibleInView(activeView)) {
jp.skipChildren();
continue;
}
try {
prop.deserializeAndSet(jp, ctxt, bean);
} catch (Exception e) {
wrapAndThrow(e, bean, propName, ctxt);
}
continue;
}
// ignorable things should be ignored
if (_ignorableProps != null && _ignorableProps.contains(propName)) {
handleIgnoredProperty(jp, ctxt, bean, propName);
continue;
}
// but others are likely to be part of external type id thingy...
if (ext.handlePropertyValue(jp, ctxt, propName, bean)) {
continue;
}
// if not, the usual fallback handling:
if (_anySetter != null) {
try {
_anySetter.deserializeAndSet(jp, ctxt, bean, propName);
} catch (Exception e) {
wrapAndThrow(e, bean, propName, ctxt);
}
continue;
}
// Unknown: let's call handler method
handleUnknownProperty(jp, ctxt, bean, propName);
}
// and when we get this far, let's try finalizing the deal:
return ext.complete(jp, ctxt, bean);
}
@SuppressWarnings("resource")
protected Object deserializeUsingPropertyBasedWithExternalTypeId(JsonParser jp, DeserializationContext ctxt)
throws IOException, JsonProcessingException
{
final ExternalTypeHandler ext = _externalTypeIdHandler.start();
final PropertyBasedCreator creator = _propertyBasedCreator;
PropertyValueBuffer buffer = creator.startBuilding(jp, ctxt, _objectIdReader);
TokenBuffer tokens = new TokenBuffer(jp);
tokens.writeStartObject();
JsonToken t = jp.getCurrentToken();
for (; t == JsonToken.FIELD_NAME; t = jp.nextToken()) {
String propName = jp.getCurrentName();
jp.nextToken(); // to point to value
// creator property?
SettableBeanProperty creatorProp = creator.findCreatorProperty(propName);
if (creatorProp != null) {
// first: let's check to see if this might be part of value with external type id:
if (ext.handlePropertyValue(jp, ctxt, propName, buffer)) {
;
} else {
// Last creator property to set?
Object value = creatorProp.deserialize(jp, ctxt);
if (buffer.assignParameter(creatorProp.getCreatorIndex(), value)) {
t = jp.nextToken(); // to move to following FIELD_NAME/END_OBJECT
Object bean;
try {
bean = creator.build(ctxt, buffer);
} catch (Exception e) {
wrapAndThrow(e, _beanType.getRawClass(), propName, ctxt);
continue; // never gets here
}
// if so, need to copy all remaining tokens into buffer
while (t == JsonToken.FIELD_NAME) {
jp.nextToken(); // to skip name
tokens.copyCurrentStructure(jp);
t = jp.nextToken();
}
if (bean.getClass() != _beanType.getRawClass()) {
// !!! 08-Jul-2011, tatu: Could probably support; but for now
// it's too complicated, so bail out
throw ctxt.mappingException("Can not create polymorphic instances with unwrapped values");
}
return ext.complete(jp, ctxt, bean);
}
}
continue;
}
// Object Id property?
if (buffer.readIdProperty(propName)) {
continue;
}
// regular property? needs buffering
SettableBeanProperty prop = _beanProperties.find(propName);
if (prop != null) {
buffer.bufferProperty(prop, prop.deserialize(jp, ctxt));
continue;
}
// external type id (or property that depends on it)?
if (ext.handlePropertyValue(jp, ctxt, propName, null)) {
continue;
}
/* As per [JACKSON-313], things marked as ignorable should not be
* passed to any setter
*/
if (_ignorableProps != null && _ignorableProps.contains(propName)) {
handleIgnoredProperty(jp, ctxt, handledType(), propName);
continue;
}
// "any property"?
if (_anySetter != null) {
buffer.bufferAnyProperty(_anySetter, propName, _anySetter.deserialize(jp, ctxt));
}
}
// We hit END_OBJECT; resolve the pieces:
try {
return ext.complete(jp, ctxt, buffer, creator);
} catch (Exception e) {
wrapInstantiationProblem(e, ctxt);
return null; // never gets here
}
}
}