Package uk.gov.gchq.gaffer.jsonserialisation

Class JSONSerialiser

java.lang.Object

uk.gov.gchq.gaffer.jsonserialisation.JSONSerialiser

public class JSONSerialiser
extends Object

A JSONSerialiser provides the ability to serialise and deserialise to/from JSON. The serialisation is set to not include nulls or default values.

JSONSerialiser is a singleton. The behaviour of the ObjectMapper can be configured by extending this class and configuring the ObjectMapper. Child classes must has a default no argument constructor. You will then need to set the gaffer.serialiser.json.class property in your StoreProperties or as a System Property. You can also add modules to the ObjectMapper by writing an implementation of JSONSerialiserModules and registering it using the gaffer.serialiser.json.modules property in your StoreProperties or as a System Property.

Once the singleton instance has been instantiated it will not be updated, unless update() or update(jsonSerialiserClass, jsonSerialiserModules) is called. An update will be done automatically in the REST API when it is first initialised and also when a Store is initialised.

Field Summary

Fields

Modifier and Type	Field	Description
static String	DEFAULT_SERIALISER_CLASS_NAME
static String	FILTER_FIELDS_BY_NAME
static String	JSON_SERIALISER_CLASS_KEY
static String	JSON_SERIALISER_MODULES	CSV of JSONSerialiserModules class names.
static String	STRICT_JSON
static boolean	STRICT_JSON_DEFAULT

Method Summary

Modifier and Type	Method	Description
static void	addSimpleClassNames(boolean includeSubtypes, Class<?>... classes)
static boolean	canHandle(Class<?> clazz)
static com.fasterxml.jackson.databind.ObjectMapper	createDefaultMapper()
static <T> T	deserialise(byte[] bytes, com.fasterxml.jackson.core.type.TypeReference<T> type)
static <T> T	deserialise(byte[] bytes, Class<T> clazz)
static <T> T	deserialise(InputStream stream, com.fasterxml.jackson.core.type.TypeReference<T> type)
static <T> T	deserialise(InputStream stream, Class<T> clazz)
static <T> T	deserialise(String json, Class<T> clazz)
static com.fasterxml.jackson.databind.ser.FilterProvider	getFilterProvider(String... fieldsToExclude)
static JSONSerialiser	getInstance()
static com.fasterxml.jackson.databind.JsonNode	getJsonNodeFromString(String content)
static com.fasterxml.jackson.databind.ObjectMapper	getMapper()
static byte[]	serialise(Object object, boolean prettyPrint, String... fieldsToExclude)	Serialises an object.
static void	serialise(Object object, com.fasterxml.jackson.core.JsonGenerator jsonGenerator, boolean prettyPrint, String... fieldsToExclude)	Serialises an object using the provided json generator.
static byte[]	serialise(Object object, String... fieldsToExclude)	Serialises an object.
static void	update()
static void	update(String jsonSerialiserClass, String jsonSerialiserModules, Boolean strictJson)	Update the json serialiser with the provided custom properties.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

JSON_SERIALISER_CLASS_KEY

public static final String JSON_SERIALISER_CLASS_KEY

See Also:

Constant Field Values

JSON_SERIALISER_MODULES

public static final String JSON_SERIALISER_MODULES

CSV of JSONSerialiserModules class names. These modules will be added to the ObjectMapper.

See Also:

Constant Field Values

DEFAULT_SERIALISER_CLASS_NAME

public static final String DEFAULT_SERIALISER_CLASS_NAME

STRICT_JSON

public static final String STRICT_JSON

See Also:

Constant Field Values

STRICT_JSON_DEFAULT

public static final boolean STRICT_JSON_DEFAULT

See Also:

Constant Field Values

FILTER_FIELDS_BY_NAME

public static final String FILTER_FIELDS_BY_NAME

See Also:

Constant Field Values

Method Detail

addSimpleClassNames

public static void addSimpleClassNames(boolean includeSubtypes,
                                       Class<?>... classes)

update

public static void update(String jsonSerialiserClass,
                          String jsonSerialiserModules,
                          Boolean strictJson)

Update the json serialiser with the provided custom properties.

Parameters:

jsonSerialiserClass - the json serialiser class to use (or null to use the default)

jsonSerialiserModules - any extra json serialiser modules required

strictJson - true if strict json conversion should be used

update

public static void update()

createDefaultMapper

public static com.fasterxml.jackson.databind.ObjectMapper createDefaultMapper()

getFilterProvider

public static com.fasterxml.jackson.databind.ser.FilterProvider getFilterProvider(String... fieldsToExclude)

canHandle

public static boolean canHandle(Class<?> clazz)

Parameters:

clazz - the clazz of the object to be serialised/deserialised

Returns:

true if the clazz can be serialised/deserialised

serialise

public static byte[] serialise(Object object,
                               String... fieldsToExclude)
                        throws SerialisationException

Serialises an object.

Parameters:

object - the object to be serialised

fieldsToExclude - optional property names to exclude from the json

Returns:

the provided object serialised into bytes

Throws:

SerialisationException - if the object fails to be serialised

serialise

public static byte[] serialise(Object object,
                               boolean prettyPrint,
                               String... fieldsToExclude)
                        throws SerialisationException

Serialises an object.

Parameters:

object - the object to be serialised

prettyPrint - true if the object should be serialised with pretty printing

fieldsToExclude - optional property names to exclude from the json

Returns:

the provided object serialised (with pretty printing) into bytes

Throws:

SerialisationException - if the object fails to serialise

serialise

public static void serialise(Object object,
                             com.fasterxml.jackson.core.JsonGenerator jsonGenerator,
                             boolean prettyPrint,
                             String... fieldsToExclude)
                      throws SerialisationException

Serialises an object using the provided json generator.

Parameters:

object - the object to be serialised and written to file

jsonGenerator - the JsonGenerator to use to write the object to

prettyPrint - true if the object should be serialised with pretty printing

fieldsToExclude - optional property names to exclude from the json

Throws:

SerialisationException - if the object fails to serialise

deserialise

public static <T> T deserialise(String json,
                                Class<T> clazz)
                         throws SerialisationException

Type Parameters:

T - the type of the object

Parameters:

json - the json of the object to deserialise

clazz - the class of the object to deserialise

Returns:

the deserialised object

Throws:

SerialisationException - if the json fails to deserialise

deserialise

public static <T> T deserialise(byte[] bytes,
                                Class<T> clazz)
                         throws SerialisationException

Type Parameters:

T - the type of the object

Parameters:

bytes - the bytes of the object to deserialise

clazz - the class of the object to deserialise

Returns:

the deserialised object

Throws:

SerialisationException - if the bytes fail to deserialise

deserialise

public static <T> T deserialise(InputStream stream,
                                Class<T> clazz)
                         throws SerialisationException

Type Parameters:

T - the type of the object

Parameters:

stream - the InputStream containing the bytes of the object to deserialise

clazz - the class of the object to deserialise

Returns:

the deserialised object

Throws:

SerialisationException - if the bytes fail to deserialise

deserialise

public static <T> T deserialise(byte[] bytes,
                                com.fasterxml.jackson.core.type.TypeReference<T> type)
                         throws SerialisationException

Type Parameters:

T - the type of the object

Parameters:

bytes - the bytes of the object to deserialise

type - the type reference of the object to deserialise

Returns:

the deserialised object

Throws:

SerialisationException - if the bytes fail to deserialise

deserialise

public static <T> T deserialise(InputStream stream,
                                com.fasterxml.jackson.core.type.TypeReference<T> type)
                         throws SerialisationException

Type Parameters:

T - the type of the object

Parameters:

stream - the InputStream containing the bytes of the object to deserialise

type - the type reference of the object to deserialise

Returns:

the deserialised object

Throws:

SerialisationException - if the bytes fail to deserialise

getJsonNodeFromString

public static com.fasterxml.jackson.databind.JsonNode getJsonNodeFromString(String content)
                                                                     throws SerialisationException

Parameters:

content - the String containing the bytes of the object to deserialise

Returns:

the deserialised object

Throws:

SerialisationException - if the bytes fail to deserialise

getMapper

public static com.fasterxml.jackson.databind.ObjectMapper getMapper()

getInstance

public static JSONSerialiser getInstance()