com.fasterxml.jackson.databind.ser.PropertyWriter Maven / Gradle / Ivy
package com.fasterxml.jackson.databind.ser;
import java.lang.annotation.Annotation;
import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.databind.jsonFormatVisitors.JsonObjectFormatVisitor;
import com.fasterxml.jackson.databind.node.ObjectNode;
/**
* Base class for writers used to output property values (name-value pairs)
* as key/value pairs via streaming API. This is the most generic abstraction
* implemented by both POJO and {@link java.util.Map} serializers, and invoked
* by filtering functionality.
*
* @since 2.3
*/
public abstract class PropertyWriter
{
/*
/**********************************************************
/* Metadata access
/**********************************************************
*/
public abstract String getName();
public abstract PropertyName getFullName();
/**
* Convenience method for accessing annotation that may be associated
* either directly on property, or, if not, via enclosing class (context).
* This allows adding baseline contextual annotations, for example, by adding
* an annotation for a given class and making that apply to all properties
* unless overridden by per-property annotations.
*
* This method is functionally equivalent to:
*
* MyAnnotation ann = propWriter.getAnnotation(MyAnnotation.class);
* if (ann == null) {
* ann = propWriter.getContextAnnotation(MyAnnotation.class);
* }
*
* that is, tries to find a property annotation first, but if one is not
* found, tries to find context-annotation (from enclosing class) of
* same type.
*
* @since 2.5
*/
public A findAnnotation(Class acls) {
A ann = getAnnotation(acls);
if (ann == null) {
ann = getContextAnnotation(acls);
}
return ann;
}
/**
* Method for accessing annotations directly declared for property that this
* writer is associated with.
*
* @since 2.5
*/
public abstract A getAnnotation(Class acls);
/**
* Method for accessing annotations declared in context of the property that this
* writer is associated with; usually this means annotations on enclosing class
* for property.
*
* @since 2.5
*/
public abstract A getContextAnnotation(Class acls);
/*
/**********************************************************
/* Serialization methods, regular output
/**********************************************************
*/
/**
* The main serialization method called by filter when property is to be written normally.
*/
public abstract void serializeAsField(Object value, JsonGenerator jgen, SerializerProvider provider)
throws Exception;
/**
* Serialization method that filter needs to call in cases where property is to be
* filtered, but the underlying data format requires a placeholder of some kind.
* This is usually the case for tabular (positional) data formats such as CSV.
*/
public abstract void serializeAsOmittedField(Object value, JsonGenerator jgen, SerializerProvider provider)
throws Exception;
/*
/**********************************************************
/* Serialization methods, explicit positional/tabular formats
/**********************************************************
*/
/**
* Serialization method called when output is to be done as an array,
* that is, not using property names. This is needed when serializing
* container ({@link java.util.Collection}, array) types,
* or POJOs using tabular ("as array") output format.
*
* Note that this mode of operation is independent of underlying
* data format; so it is typically NOT called for fully tabular formats such as CSV,
* where logical output is still as form of POJOs.
*/
public abstract void serializeAsElement(Object value, JsonGenerator jgen, SerializerProvider provider)
throws Exception;
/**
* Serialization method called when doing tabular (positional) output from databind,
* but then value is to be omitted. This requires output of a placeholder value
* of some sort; often similar to {@link #serializeAsOmittedField}.
*/
public abstract void serializeAsPlaceholder(Object value, JsonGenerator jgen, SerializerProvider provider)
throws Exception;
/*
/**********************************************************
/* Schema-related
/**********************************************************
*/
/**
* Traversal method used for things like JSON Schema generation, or
* POJO introspection.
*/
public abstract void depositSchemaProperty(JsonObjectFormatVisitor objectVisitor)
throws JsonMappingException;
/**
* Legacy method called for JSON Schema generation; should not be called by new code
*
* @deprecated Since 2.2
*/
@Deprecated
public abstract void depositSchemaProperty(ObjectNode propertiesNode, SerializerProvider provider)
throws JsonMappingException;
}