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package com.fasterxml.jackson.databind.ser;
import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.databind.annotation.JsonSerialize;
import com.fasterxml.jackson.databind.introspect.*;
import com.fasterxml.jackson.databind.jsontype.TypeSerializer;
import com.fasterxml.jackson.databind.util.*;
/**
* Helper class for {@link BeanSerializerFactory} that is used to
* construct {@link BeanPropertyWriter} instances. Can be sub-classed
* to change behavior.
*/
public class PropertyBuilder
{
// @since 2.7
private final static Object NO_DEFAULT_MARKER = Boolean.FALSE;
final protected SerializationConfig _config;
final protected BeanDescription _beanDesc;
/**
* Default inclusion mode for properties of the POJO for which
* properties are collected; possibly overridden on
* per-property basis.
*/
final protected JsonInclude.Value _defaultInclusion;
final protected AnnotationIntrospector _annotationIntrospector;
/**
* If a property has serialization inclusion value of
* {@link com.fasterxml.jackson.annotation.JsonInclude.Include#NON_DEFAULT},
* we may need to know the default value of the bean, to know if property value
* equals default one.
*
* NOTE: only used if enclosing class defines NON_DEFAULT, but NOT if it is the
* global default OR per-property override.
*/
protected Object _defaultBean;
public PropertyBuilder(SerializationConfig config, BeanDescription beanDesc)
{
_config = config;
_beanDesc = beanDesc;
_defaultInclusion = beanDesc.findPropertyInclusion(config.getDefaultPropertyInclusion());
_annotationIntrospector = _config.getAnnotationIntrospector();
}
/*
/**********************************************************
/* Public API
/**********************************************************
*/
public Annotations getClassAnnotations() {
return _beanDesc.getClassAnnotations();
}
/**
* @param contentTypeSer Optional explicit type information serializer
* to use for contained values (only used for properties that are
* of container type)
*/
protected BeanPropertyWriter buildWriter(SerializerProvider prov,
BeanPropertyDefinition propDef, JavaType declaredType, JsonSerializer ser,
TypeSerializer typeSer, TypeSerializer contentTypeSer,
AnnotatedMember am, boolean defaultUseStaticTyping)
throws JsonMappingException
{
// do we have annotation that forces type to use (to declared type or its super type)?
JavaType serializationType = findSerializationType(am, defaultUseStaticTyping, declaredType);
// Container types can have separate type serializers for content (value / element) type
if (contentTypeSer != null) {
/* 04-Feb-2010, tatu: Let's force static typing for collection, if there is
* type information for contents. Should work well (for JAXB case); can be
* revisited if this causes problems.
*/
if (serializationType == null) {
// serializationType = TypeFactory.type(am.getGenericType(), _beanDesc.getType());
serializationType = declaredType;
}
JavaType ct = serializationType.getContentType();
// Not exactly sure why, but this used to occur; better check explicitly:
if (ct == null) {
throw new IllegalStateException("Problem trying to create BeanPropertyWriter for property '"
+propDef.getName()+"' (of type "+_beanDesc.getType()+"); serialization type "+serializationType+" has no content");
}
serializationType = serializationType.withContentTypeHandler(contentTypeSer);
ct = serializationType.getContentType();
}
Object valueToSuppress = null;
boolean suppressNulls = false;
JsonInclude.Value inclV = _defaultInclusion.withOverrides(propDef.findInclusion());
JsonInclude.Include inclusion = inclV.getValueInclusion();
if (inclusion == JsonInclude.Include.USE_DEFAULTS) { // should not occur but...
inclusion = JsonInclude.Include.ALWAYS;
}
/*
JsonInclude.Include inclusion = propDef.findInclusion().getValueInclusion();
if (inclusion == JsonInclude.Include.USE_DEFAULTS) { // since 2.6
inclusion = _defaultInclusion;
if (inclusion == null) {
inclusion = JsonInclude.Include.ALWAYS;
}
}
*/
switch (inclusion) {
case NON_DEFAULT:
// 11-Nov-2015, tatu: This is tricky because semantics differ between cases,
// so that if enclosing class has this, we may need to values of property,
// whereas for global defaults OR per-property overrides, we have more
// static definition. Sigh.
// First: case of class specifying it; try to find POJO property defaults
JavaType t = (serializationType == null) ? declaredType : serializationType;
if (_defaultInclusion.getValueInclusion() == JsonInclude.Include.NON_DEFAULT) {
valueToSuppress = getPropertyDefaultValue(propDef.getName(), am, t);
} else {
valueToSuppress = getDefaultValue(t);
}
if (valueToSuppress == null) {
suppressNulls = true;
} else {
if (valueToSuppress.getClass().isArray()) {
valueToSuppress = ArrayBuilders.getArrayComparator(valueToSuppress);
}
}
break;
case NON_ABSENT: // new with 2.6, to support Guava/JDK8 Optionals
// always suppress nulls
suppressNulls = true;
// and for referential types, also "empty", which in their case means "absent"
if (declaredType.isReferenceType()) {
valueToSuppress = BeanPropertyWriter.MARKER_FOR_EMPTY;
}
break;
case NON_EMPTY:
// always suppress nulls
suppressNulls = true;
// but possibly also 'empty' values:
valueToSuppress = BeanPropertyWriter.MARKER_FOR_EMPTY;
break;
case NON_NULL:
suppressNulls = true;
// fall through
case ALWAYS: // default
default:
// we may still want to suppress empty collections, as per [JACKSON-254]:
if (declaredType.isContainerType()
&& !_config.isEnabled(SerializationFeature.WRITE_EMPTY_JSON_ARRAYS)) {
valueToSuppress = BeanPropertyWriter.MARKER_FOR_EMPTY;
}
break;
}
BeanPropertyWriter bpw = new BeanPropertyWriter(propDef,
am, _beanDesc.getClassAnnotations(), declaredType,
ser, typeSer, serializationType, suppressNulls, valueToSuppress);
// How about custom null serializer?
Object serDef = _annotationIntrospector.findNullSerializer(am);
if (serDef != null) {
bpw.assignNullSerializer(prov.serializerInstance(am, serDef));
}
// And then, handling of unwrapping
NameTransformer unwrapper = _annotationIntrospector.findUnwrappingNameTransformer(am);
if (unwrapper != null) {
bpw = bpw.unwrappingWriter(unwrapper);
}
return bpw;
}
/*
/**********************************************************
/* Helper methods; annotation access
/**********************************************************
*/
/**
* Method that will try to determine statically defined type of property
* being serialized, based on annotations (for overrides), and alternatively
* declared type (if static typing for serialization is enabled).
* If neither can be used (no annotations, dynamic typing), returns null.
*/
protected JavaType findSerializationType(Annotated a, boolean useStaticTyping, JavaType declaredType)
throws JsonMappingException
{
JavaType secondary = _annotationIntrospector.refineSerializationType(_config, a, declaredType);
// 11-Oct-2015, tatu: As of 2.7, not 100% sure following checks are needed. But keeping
// for now, just in case
if (secondary != declaredType) {
Class serClass = secondary.getRawClass();
// Must be a super type to be usable
Class rawDeclared = declaredType.getRawClass();
if (serClass.isAssignableFrom(rawDeclared)) {
; // fine as is
} else {
/* 18-Nov-2010, tatu: Related to fixing [JACKSON-416], an issue with such
* check is that for deserialization more specific type makes sense;
* and for serialization more generic. But alas JAXB uses but a single
* annotation to do both... Hence, we must just discard type, as long as
* types are related
*/
if (!rawDeclared.isAssignableFrom(serClass)) {
throw new IllegalArgumentException("Illegal concrete-type annotation for method '"+a.getName()+"': class "+serClass.getName()+" not a super-type of (declared) class "+rawDeclared.getName());
}
/* 03-Dec-2010, tatu: Actually, ugh, we may need to further relax this
* and actually accept subtypes too for serialization. Bit dangerous in theory
* but need to trust user here...
*/
}
useStaticTyping = true;
declaredType = secondary;
}
// If using static typing, declared type is known to be the type...
JsonSerialize.Typing typing = _annotationIntrospector.findSerializationTyping(a);
if ((typing != null) && (typing != JsonSerialize.Typing.DEFAULT_TYPING)) {
useStaticTyping = (typing == JsonSerialize.Typing.STATIC);
}
if (useStaticTyping) {
// 11-Oct-2015, tatu: Make sure JavaType also "knows" static-ness...
return declaredType.withStaticTyping();
}
return null;
}
/*
/**********************************************************
/* Helper methods for default value handling
/**********************************************************
*/
protected Object getDefaultBean()
{
Object def = _defaultBean;
if (def == null) {
/* If we can fix access rights, we should; otherwise non-public
* classes or default constructor will prevent instantiation
*/
def = _beanDesc.instantiateBean(_config.canOverrideAccessModifiers());
if (def == null) {
// 06-Nov-2015, tatu: As per [databind#998], do not fail.
/*
Class cls = _beanDesc.getClassInfo().getAnnotated();
throw new IllegalArgumentException("Class "+cls.getName()+" has no default constructor; can not instantiate default bean value to support 'properties=JsonSerialize.Inclusion.NON_DEFAULT' annotation");
*/
// And use a marker
def = NO_DEFAULT_MARKER;
}
_defaultBean = def;
}
return (def == NO_DEFAULT_MARKER) ? null : _defaultBean;
}
/**
* Accessor used to find out "default value" for given property, to use for
* comparing values to serialize, to determine whether to exclude value from serialization with
* inclusion type of {@link com.fasterxml.jackson.annotation.JsonInclude.Include#NON_EMPTY}.
* This method is called when we specifically want to know default value within context
* of a POJO, when annotation is within containing class, and not for property or
* defined as global baseline.
*
* Note that returning of pseudo-type
*
* @since 2.7
*/
protected Object getPropertyDefaultValue(String name, AnnotatedMember member,
JavaType type)
{
Object defaultBean = getDefaultBean();
if (defaultBean == null) {
return getDefaultValue(type);
}
try {
return member.getValue(defaultBean);
} catch (Exception e) {
return _throwWrapped(e, name, defaultBean);
}
}
/**
* Accessor used to find out "default value" to use for comparing values to
* serialize, to determine whether to exclude value from serialization with
* inclusion type of {@link com.fasterxml.jackson.annotation.JsonInclude.Include#NON_DEFAULT}.
*
* Default logic is such that for primitives and wrapper types for primitives, expected
* defaults (0 for `int` and `java.lang.Integer`) are returned; for Strings, empty String,
* and for structured (Maps, Collections, arrays) and reference types, criteria
* {@link com.fasterxml.jackson.annotation.JsonInclude.Include#NON_DEFAULT}
* is used.
*
* @since 2.7
*/
protected Object getDefaultValue(JavaType type)
{
// 06-Nov-2015, tatu: Returning null is fine for Object types; but need special
// handling for primitives since they are never passed as nulls.
Class cls = type.getRawClass();
Class prim = ClassUtil.primitiveType(cls);
if (prim != null) {
return ClassUtil.defaultValue(prim);
}
if (type.isContainerType() || type.isReferenceType()) {
return JsonInclude.Include.NON_EMPTY;
}
if (cls == String.class) {
return "";
}
return null;
}
/*
/**********************************************************
/* Helper methods for exception handling
/**********************************************************
*/
protected Object _throwWrapped(Exception e, String propName, Object defaultBean)
{
Throwable t = e;
while (t.getCause() != null) {
t = t.getCause();
}
if (t instanceof Error) throw (Error) t;
if (t instanceof RuntimeException) throw (RuntimeException) t;
throw new IllegalArgumentException("Failed to get property '"+propName+"' of default "+defaultBean.getClass().getName()+" instance");
}
}