com.esotericsoftware.kryo.serializers
Class FieldSerializer<T>

java.lang.Object
  extended by com.esotericsoftware.kryo.Serializer<T>
      extended by com.esotericsoftware.kryo.serializers.FieldSerializer<T>
All Implemented Interfaces:
java.util.Comparator<FieldSerializer.CachedField>
Direct Known Subclasses:
CompatibleFieldSerializer, TaggedFieldSerializer

public class FieldSerializer<T>
extends Serializer<T>
implements java.util.Comparator<FieldSerializer.CachedField>

Serializes objects using direct field assignment. No header or schema data is stored, only the data for each field. This reduces output size but means if any field is added or removed, previously serialized bytes are invalidated. If fields are public, bytecode generation will be used instead of reflection.

See Also:
Serializer, Kryo.register(Class, Serializer)

Nested Class Summary
 class FieldSerializer.CachedField<X>
          Controls how a field will be serialized.
static interface FieldSerializer.Optional
          Indicates a field should be ignored when its declaring class is registered unless the context has a value set for the specified key.
 
Constructor Summary
FieldSerializer(Kryo kryo, java.lang.Class type)
           
 
Method Summary
 int compare(FieldSerializer.CachedField o1, FieldSerializer.CachedField o2)
           
 T copy(Kryo kryo, T original)
          Returns a copy of the specified object.
protected  T create(Kryo kryo, Input input, java.lang.Class<T> type)
          Used by read(Kryo, Input, Class) to create the new object.
protected  T createCopy(Kryo kryo, T original)
          Used by copy(Kryo, Object) to create the new object.
 FieldSerializer.CachedField getField(java.lang.String fieldName)
          Allows specific fields to be optimized.
 FieldSerializer.CachedField[] getFields()
           
 java.lang.Class getType()
           
protected  void initializeCachedFields()
           
 T read(Kryo kryo, Input input, java.lang.Class<T> type)
          Reads bytes and returns a new object of the specified concrete type.
 void removeField(java.lang.String fieldName)
          Removes a field so that it won't be serialized.
 void setFieldsAsAccessible(boolean setFieldsAsAccessible)
          Controls which fields are serialized.
 void setFieldsCanBeNull(boolean fieldsCanBeNull)
          Sets the default value for FieldSerializer.CachedField.setCanBeNull(boolean).
 void setFixedFieldTypes(boolean fixedFieldTypes)
          Sets the default value for FieldSerializer.CachedField.setClass(Class) to the field's declared type.
 void setIgnoreSyntheticFields(boolean ignoreSyntheticFields)
          Controls if synthetic fields are serialized.
 void write(Kryo kryo, Output output, T object)
          Writes the bytes for the object to the output.
 
Methods inherited from class com.esotericsoftware.kryo.Serializer
getAcceptsNull, isImmutable, setAcceptsNull, setGenerics, setImmutable
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface java.util.Comparator
equals
 

Constructor Detail

FieldSerializer

public FieldSerializer(Kryo kryo,
                       java.lang.Class type)
Method Detail

initializeCachedFields

protected void initializeCachedFields()

compare

public int compare(FieldSerializer.CachedField o1,
                   FieldSerializer.CachedField o2)
Specified by:
compare in interface java.util.Comparator<FieldSerializer.CachedField>

setFieldsCanBeNull

public void setFieldsCanBeNull(boolean fieldsCanBeNull)
Sets the default value for FieldSerializer.CachedField.setCanBeNull(boolean). Calling this method resets the cached fields.

Parameters:
fieldsCanBeNull - False if none of the fields are null. Saves 0-1 byte per field. True if it is not known (default).

setFieldsAsAccessible

public void setFieldsAsAccessible(boolean setFieldsAsAccessible)
Controls which fields are serialized. Calling this method resets the cached fields.

Parameters:
setFieldsAsAccessible - If true, all non-transient fields (inlcuding private fields) will be serialized and set as accessible if necessary (default). If false, only fields in the public API will be serialized.

setIgnoreSyntheticFields

public void setIgnoreSyntheticFields(boolean ignoreSyntheticFields)
Controls if synthetic fields are serialized. Default is true. Calling this method resets the cached fields.

Parameters:
ignoreSyntheticFields - If true, only non-synthetic fields will be serialized.

setFixedFieldTypes

public void setFixedFieldTypes(boolean fixedFieldTypes)
Sets the default value for FieldSerializer.CachedField.setClass(Class) to the field's declared type. This allows FieldSerializer to be more efficient, since it knows field values will not be a subclass of their declared type. Default is false. Calling this method resets the cached fields.


write

public void write(Kryo kryo,
                  Output output,
                  T object)
Description copied from class: Serializer
Writes the bytes for the object to the output.

This method should not be called directly, instead this serializer can be passed to Kryo write methods that accept a serialier.

Specified by:
write in class Serializer<T>
object - May be null if Serializer.getAcceptsNull() is true.

read

public T read(Kryo kryo,
              Input input,
              java.lang.Class<T> type)
Description copied from class: Serializer
Reads bytes and returns a new object of the specified concrete type.

Before Kryo can be used to read child objects, Kryo.reference(Object) must be called with the parent object to ensure it can be referenced by the child objects. Any serializer that uses Kryo to read a child object may need to be reentrant.

This method should not be called directly, instead this serializer can be passed to Kryo read methods that accept a serialier.

Specified by:
read in class Serializer<T>
Returns:
May be null if Serializer.getAcceptsNull() is true.

create

protected T create(Kryo kryo,
                   Input input,
                   java.lang.Class<T> type)
Used by read(Kryo, Input, Class) to create the new object. This can be overridden to customize object creation, eg to call a constructor with arguments. The default implementation uses Kryo.newInstance(Class).


getField

public FieldSerializer.CachedField getField(java.lang.String fieldName)
Allows specific fields to be optimized.


removeField

public void removeField(java.lang.String fieldName)
Removes a field so that it won't be serialized.


getFields

public FieldSerializer.CachedField[] getFields()

getType

public java.lang.Class getType()

createCopy

protected T createCopy(Kryo kryo,
                       T original)
Used by copy(Kryo, Object) to create the new object. This can be overridden to customize object creation, eg to call a constructor with arguments. The default implementation uses Kryo.newInstance(Class).


copy

public T copy(Kryo kryo,
              T original)
Description copied from class: Serializer
Returns a copy of the specified object. The default implementation returns the original if Serializer.isImmutable() is true, else throws KryoException. Subclasses should override this method if needed to support Kryo.copy(Object).

Before Kryo can be used to copy child objects, Kryo.reference(Object) must be called with the copy to ensure it can be referenced by the child objects. Any serializer that uses Kryo to copy a child object may need to be reentrant.

This method should not be called directly, instead this serializer can be passed to Kryo copy methods that accept a serialier.

Overrides:
copy in class Serializer<T>