Package com.esotericsoftware.kryo.serializers

Class MapSerializer

  • Direct Known Subclasses:
    DefaultSerializers.TreeMapSerializer
    public class MapSerializer
extends Serializer<java.util.Map>
    Serializes objects that implement the Map interface.

    With the default constructor, a map requires a 1-3 byte header and an extra 4 bytes is written for each key/value pair.

    • Field Detail

      • keyClass

        private java.lang.Class keyClass

      • valueClass

        private java.lang.Class valueClass

      • valueSerializer

        private Serializer valueSerializer

      • keysCanBeNull

        private boolean keysCanBeNull

      • valuesCanBeNull

        private boolean valuesCanBeNull

      • keyGenericType

        private java.lang.Class keyGenericType

      • valueGenericType

        private java.lang.Class valueGenericType

    • Constructor Detail

      • MapSerializer

        public MapSerializer()

    • Method Detail

      • setKeysCanBeNull

        public void setKeysCanBeNull​(boolean keysCanBeNull)
        Parameters:
        keysCanBeNull - False if all keys are not null. This saves 1 byte per key if keyClass is set. True if it is not known (default).

      • setKeyClass

        public void setKeyClass​(java.lang.Class keyClass,
                        Serializer keySerializer)
        Parameters:
        keyClass - The concrete class of each key. This saves 1 byte per key. Set to null if the class is not known or varies per key (default).
        keySerializer - The serializer to use for each key.

      • setValueClass

        public void setValueClass​(java.lang.Class valueClass,
                          Serializer valueSerializer)
        Parameters:
        valueClass - The concrete class of each value. This saves 1 byte per value. Set to null if the class is not known or varies per value (default).
        valueSerializer - The serializer to use for each value.

      • setValuesCanBeNull

        public void setValuesCanBeNull​(boolean valuesCanBeNull)
        Parameters:
        valuesCanBeNull - True if values are not null. This saves 1 byte per value if keyClass is set. False if it is not known (default).

      • setGenerics

        public void setGenerics​(Kryo kryo,
                        java.lang.Class[] generics)
        Description copied from class: Serializer
        Sets the generic types of the field or method this serializer will be used for on the next call to read or write. Subsequent calls to read and write must not use this generic type information. The default implementation does nothing. Subclasses may use the information provided to this method for more efficient serialization, eg to use the same type for all items in a list.
        Overrides:
        setGenerics in class Serializer<java.util.Map>
        generics - Some (but never all) elements may be null if there is no generic type information at that index.

      • write

        public void write​(Kryo kryo,
                  Output output,
                  java.util.Map map)
        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<java.util.Map>
        map - May be null if Serializer.getAcceptsNull() is true.

      • create

        protected java.util.Map create​(Kryo kryo,
                               Input input,
                               java.lang.Class<java.util.Map> 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).

      • read

        public java.util.Map read​(Kryo kryo,
                          Input input,
                          java.lang.Class<java.util.Map> 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<java.util.Map>
        Returns:
        May be null if Serializer.getAcceptsNull() is true.

      • createCopy

        protected java.util.Map createCopy​(Kryo kryo,
                                   java.util.Map original)

      • copy

        public java.util.Map copy​(Kryo kryo,
                          java.util.Map 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<java.util.Map>