package org.codehaus.jackson.map.ser;
import org.codehaus.jackson.JsonGenerator;
import org.codehaus.jackson.map.JsonMappingException;
import org.codehaus.jackson.map.JsonSerializer;
import org.codehaus.jackson.map.SerializerProvider;
import org.codehaus.jackson.map.TypeSerializer;
import org.codehaus.jackson.type.JavaType;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.lang.reflect.Type;
/**
* Base bean property handler class, which implements common parts of
* reflection-based functionality for accessing a property value
* and serializing it.
*/
public class BeanPropertyWriter
{
/*
/*****************************************************
/* Settings for accessing property value to serialize
/*****************************************************
*/
/**
* Accessor method used to get property value, for
* method-accessible properties.
* Null if and only if {@link #_field} is null.
*/
protected final Method _accessorMethod;
/**
* Field that contains the property value for field-accessible
* properties.
* Null if and only if {@link #_accessorMethod} is null.
*/
protected final Field _field;
/*
/*****************************************************
/* Serialization settings
/*****************************************************
*/
/**
* Logical name of the property; will be used as the field name
* under which value for the property is written.
*/
protected final String _name;
/**
* Type to use for locating serializer; normally same as return
* type of the accessor method, but may be overridden by annotations.
*/
protected final JavaType _cfgSerializationType;
/**
* Serializer to use for writing out the value: null if it can not
* be known statically; non-null if it can.
*/
protected final JsonSerializer<Object> _serializer;
/**
* Flag to indicate that null values for this property are not
* to be written out. That is, if property has value null,
* no entry will be written
*/
protected final boolean _suppressNulls;
/**
* Value that is considered default value of the property; used for
* default-value-suppression if enabled.
*/
protected final Object _suppressableValue;
/**
* Alternate set of property writers used when view-based filtering
* is available for the Bean.
*
* @since 1.4
*/
protected Class<?>[] _includeInViews;
/**
* If property being serialized needs type information to be
* included this is the type serializer to use.
* Declared type (possibly augmented with annotations) of property
* is used for determining exact mechanism to use (compared to
* actual runtime type used for serializing actual state).
*/
protected TypeSerializer _typeSerializer;
/**
* Base type of the property, if the declared type is "non-trivial";
* meaning it is either a structured type (collection, map, array),
* or parametrized. Used to retain type information about contained
* type, which is mostly necessary if type metadata is to be
* included.
*
* @since 1.5
*/
protected JavaType _nonTrivialBaseType;
/*
/*****************************************************
/* Construction, configuration
/*****************************************************
*/
/**
*
* @param suppressableValue Value to suppress
*/
public BeanPropertyWriter(String name, JsonSerializer<Object> ser, TypeSerializer typeSer,
JavaType serType,
Method acc, Field f,
boolean suppressNulls,
Object suppressableValue)
{
_name = name;
_serializer = ser;
_typeSerializer = typeSer;
_cfgSerializationType = serType;
_accessorMethod = acc;
_field = f;
_suppressNulls = suppressNulls;
_suppressableValue = suppressableValue;
}
/**
* "Copy constructor" to be used by filtering sub-classes
*/
protected BeanPropertyWriter(BeanPropertyWriter base)
{
_name = base._name;
_serializer = base._serializer;
_typeSerializer = base._typeSerializer;
_cfgSerializationType = base._cfgSerializationType;
_accessorMethod = base._accessorMethod;
_field = base._field;
_suppressNulls = base._suppressNulls;
_suppressableValue = base._suppressableValue;
}
/**
* Method that will construct and return a new writer that has
* same properties as this writer, but uses specified serializer
* instead of currently configured one (if any).
*/
public BeanPropertyWriter withSerializer(JsonSerializer<Object> ser)
{
return new BeanPropertyWriter(_name, ser, _typeSerializer, _cfgSerializationType,
_accessorMethod, _field,
_suppressNulls, _suppressableValue);
}
/**
* Method for defining which views to included value of this
* property in. If left undefined, will always be included;
* otherwise active view definition will be checked against
* definition list and value is only included if active
* view is one of defined views, or its sub-view (as defined
* by class/sub-class relationship).
*/
public void setViews(Class<?>[] views) { _includeInViews = views; }
/**
* Method called to define type to consider as "non-trivial" basetype,
* needed for dynamic serialization resolution for complex (usually container)
* types
*
* @since 1.5
*/
public void setNonTrivialBaseType(JavaType t) {
_nonTrivialBaseType = t;
}
/*
/*****************************************************
/* Accessors
/*****************************************************
*/
public final String getName() { return _name; }
public boolean hasSerializer() { return _serializer != null; }
// Needed by BeanSerializer#getSchema
protected JsonSerializer<Object> getSerializer() {
return _serializer;
}
public JavaType getSerializationType() {
return _cfgSerializationType;
}
public Class<?> getRawSerializationType() {
return (_cfgSerializationType == null) ? null : _cfgSerializationType.getRawClass();
}
public Class<?> getPropertyType()
{
if (_accessorMethod != null) {
return _accessorMethod.getReturnType();
}
return _field.getType();
}
/**
* Get the generic property type of this property writer.
*
* @return The property type, or null if not found.
*/
public Type getGenericPropertyType()
{
if (_accessorMethod != null) {
return _accessorMethod.getGenericReturnType();
}
return _field.getGenericType();
}
public Class<?>[] getViews() { return _includeInViews; }
/*
/*****************************************************
/* Serialization functionality
/*****************************************************
*/
/**
* Method called to access property that this bean stands for, from
* within given bean, and to serialize it as a JSON Object field
* using appropriate serializer.
*/
public void serializeAsField(Object bean, JsonGenerator jgen, SerializerProvider prov)
throws Exception
{
Object value = get(bean);
// Null handling is bit different, check that first
if (value == null) {
if (!_suppressNulls) {
jgen.writeFieldName(_name);
prov.getNullValueSerializer().serialize(value, jgen, prov);
}
return;
}
// For non-nulls, first: simple check for direct cycles
if (value == bean) {
_reportSelfReference(bean);
}
if (_suppressableValue != null && _suppressableValue.equals(value)) {
return;
}
JsonSerializer<Object> ser = _serializer;
if (ser == null) {
Class<?> cls = value.getClass();
if (_nonTrivialBaseType != null) {
JavaType t = _nonTrivialBaseType.forcedNarrowBy(cls);
ser = prov.findValueSerializer(t);
} else {
ser = prov.findValueSerializer(cls);
}
}
jgen.writeFieldName(_name);
if (_typeSerializer == null) {
ser.serialize(value, jgen, prov);
} else {
ser.serializeWithType(value, jgen, prov, _typeSerializer);
}
}
/**
* Method that can be used to access value of the property this
* Object describes, from given bean instance.
*<p>
* Note: method is final as it should not need to be overridden -- rather,
* calling method(s) ({@link #serializeAsField}) should be overridden
* to change the behavior
*/
public final Object get(Object bean) throws Exception
{
if (_accessorMethod != null) {
return _accessorMethod.invoke(bean);
}
return _field.get(bean);
}
@Override
public String toString()
{
StringBuilder sb = new StringBuilder(40);
sb.append("property '").append(getName()).append("' (");
if (_accessorMethod != null) {
sb.append("via method ").append(_accessorMethod.getDeclaringClass().getName()).append("#").append(_accessorMethod.getName());
} else {
sb.append("field \"").append(_field.getDeclaringClass().getName()).append("#").append(_field.getName());
}
sb.append(')');
return sb.toString();
}
protected void _reportSelfReference(Object bean)
throws JsonMappingException
{
throw new JsonMappingException("Direct self-reference leading to cycle");
}
}