Package org.jolokia.service.serializer.json

Class ObjectToJsonConverter

java.lang.Object

org.jolokia.service.serializer.json.ObjectToJsonConverter

public final class ObjectToJsonConverter
extends Object

A converter/serializer that transforms Java objects (JMX attribute values, JMX operation parameters and return values) into a JSON representation. It delegates handling of supported types to ObjectAccessor implementations.

Each ObjectAccessor gets a reference to this converter object so it can use it for a recursive serialization of nested objects.

Additionally (since the dawn of Jolokia) this converter is used to set inner values of any objects. Also by delegating to extractors which can handle particular object types. For example DateAccessor can call Date.setTime(long).

Since:

Apr 19, 2009

Author:

roland

Field Summary

Fields

Modifier and Type	Field	Description
static final Set<Class<?>>	JSON_BASIC_TYPES	Classes of the objects that can be returned directly as proper JSON types and can't be used with extra "path" do return part of the value.
static final Map<Class<?>,String>	JSON_CONVERSIONS	Simple types which are not proper JSON types (even if they seem to) but can be easily converted.
static final Set<Class<?>>	JSON_TYPES	Classes of the objects that can be returned directly as proper JSON types.

Constructor Summary

Constructors

Constructor	Description
ObjectToJsonConverter(ObjectToObjectConverter pObjectToObjectConverter, ObjectToOpenTypeConverter pObjectToOpenTypeConverter, org.jolokia.server.core.service.api.JolokiaContext pContext)	Create a converter that can serialize objects into JSON representation

Method Summary

Modifier and Type	Method	Description
Object	extractObject(Object pValue, Deque<String> pPathParts, boolean pJsonify)	Related to extractObjectWithContext(java.lang.Object, java.util.Deque<java.lang.String>, org.jolokia.server.core.service.serializer.SerializeOptions, boolean) except that it does not set up a context.
org.jolokia.server.core.service.serializer.ValueFaultHandler	getValueFaultHandler()	Get the fault handler used for dealing with exceptions during value extraction.
Object	serialize(Object pValue, List<String> pPathParts, org.jolokia.server.core.service.serializer.SerializeOptions pOptions)	Convert the return value to a JSON object.
Object	setInnerValue(Object pOuterObject, Object pNewValue, List<String> pPathParts)	Set an inner value of a complex object.

Methods inherited from class java.lang.Object

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

Field Details

JSON_TYPES

public static final Set<Class<?>> JSON_TYPES

Classes of the objects that can be returned directly as proper JSON types. All other objects need to be converted in some way to proper JSON objects.

JSON_BASIC_TYPES

public static final Set<Class<?>> JSON_BASIC_TYPES

Classes of the objects that can be returned directly as proper JSON types and can't be used with extra "path" do return part of the value.

JSON_CONVERSIONS

public static final Map<Class<?>,String> JSON_CONVERSIONS

Simple types which are not proper JSON types (even if they seem to) but can be easily converted.

Constructor Details

ObjectToJsonConverter

public ObjectToJsonConverter(ObjectToObjectConverter pObjectToObjectConverter,
 ObjectToOpenTypeConverter pObjectToOpenTypeConverter,
 org.jolokia.server.core.service.api.JolokiaContext pContext)

Create a converter that can serialize objects into JSON representation

Parameters:

pObjectToObjectConverter - used when setting values

pObjectToOpenTypeConverter - used when converting TabularData

pContext - JolokiaContext used to load ObjectAccessor services

Method Details

serialize

public Object serialize(Object pValue,
 List<String> pPathParts,
 org.jolokia.server.core.service.serializer.SerializeOptions pOptions)
                 throws AttributeNotFoundException

Convert the return value to a JSON object.

Parameters:

pValue - the value to convert

pPathParts - path parts to use for extraction

pOptions - options used for parsing

Returns:

the converter object. This either a subclass of JSONStructure or a basic data type like String or Long.

Throws:

AttributeNotFoundException - if within a path an attribute could not be found

setInnerValue

public Object setInnerValue(Object pOuterObject,
 Object pNewValue,
 List<String> pPathParts)
                     throws AttributeNotFoundException,
IllegalAccessException,
InvocationTargetException

Set an inner value of a complex object. A given path must point to the attribute/index to set within the outer object.

Parameters:

pOuterObject - the object to dive in

pNewValue - the value to set

pPathParts - the path within the outer object. This object will be modified and must be a modifiable list.

Returns:

the old value

Throws:

AttributeNotFoundException

IllegalAccessException

InvocationTargetException

extractObject

public Object extractObject(Object pValue,
 Deque<String> pPathParts,
 boolean pJsonify)
                     throws AttributeNotFoundException

Related to extractObjectWithContext(java.lang.Object, java.util.Deque<java.lang.String>, org.jolokia.server.core.service.serializer.SerializeOptions, boolean) except that it does not set up a context. This method is called back from the various extractors to recursively continue the extraction, hence it is public.

This method must not be used as entry point for serialization. Use serialize(Object, List, SerializeOptions) or setInnerValue(Object, Object, List) instead.

Parameters:

pValue - value to extract from

pPathParts - stack for diving into the object

pJsonify - whether a JSON representation JSONObject

Returns:

extracted object either in native format or as JSONObject

Throws:

AttributeNotFoundException - if an attribute is not found during traversal

getValueFaultHandler

public org.jolokia.server.core.service.serializer.ValueFaultHandler getValueFaultHandler()

Get the fault handler used for dealing with exceptions during value extraction.

Returns:

the fault handler