Package com.gravity9.jsonpatch

Class JsonPatch

java.lang.Object

com.gravity9.jsonpatch.JsonPatch

All Implemented Interfaces:

com.fasterxml.jackson.databind.JsonSerializable, Patch

public final class JsonPatch
extends java.lang.Object
implements com.fasterxml.jackson.databind.JsonSerializable, Patch

Implementation of JSON Patch

JSON Patch, as its name implies, is an IETF RFC describing a mechanism to apply a patch to any JSON value. This implementation covers all operations according to the specification; however, there are some subtle differences with regards to some operations which are covered in these operations' respective documentation.

An example of a JSON Patch is as follows:

     [
         {
             "op": "add",
             "path": "/-",
             "value": {
                 "productId": 19,
                 "name": "Duvel",
                 "type": "beer"
             }
         }
     ]
 

This patch contains a single operation which adds an item at the end of an array. A JSON Patch can contain more than one operation; in this case, all operations are applied to the input JSON value in their order of appearance, until all operations are applied or an error condition is encountered.

The main point where this implementation differs from the specification is initial JSON parsing. The draft says:

     Operation objects MUST have exactly one "op" member
 

and:

     Additionally, operation objects MUST have exactly one "path" member.
 

However, obeying these to the letter forces constraints on the JSON parser. Here, these constraints are not enforced, which means:

     [ { "op": "add", "op": "remove", "path": "/x" } ]
 

is parsed (as a remove operation, since it appears last).

IMPORTANT NOTE: the JSON Patch is supposed to be VALID when the constructor for this class (fromJson(JsonNode) is used.

Nested Class Summary

Nested classes/interfaces inherited from interface com.fasterxml.jackson.databind.JsonSerializable

com.fasterxml.jackson.databind.JsonSerializable.Base

Constructor Summary

Constructors

Constructor	Description
JsonPatch(java.util.List<JsonPatchOperation> operations)	Constructor

Method Summary

Modifier and Type	Method	Description
com.fasterxml.jackson.databind.JsonNode	apply(com.fasterxml.jackson.databind.JsonNode node)	Apply this patch to a JSON value
static JsonPatch	fromJson(com.fasterxml.jackson.databind.JsonNode node)	Static factory method to build a JSON Patch out of a JSON representation
java.util.List<JsonPatchOperation>	getOperations()
void	serialize(com.fasterxml.jackson.core.JsonGenerator jgen, com.fasterxml.jackson.databind.SerializerProvider provider)
void	serializeWithType(com.fasterxml.jackson.core.JsonGenerator jgen, com.fasterxml.jackson.databind.SerializerProvider provider, com.fasterxml.jackson.databind.jsontype.TypeSerializer typeSer)
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

JsonPatch

public JsonPatch(java.util.List<JsonPatchOperation> operations)

Constructor

Normally, you should never have to use it.

Parameters:

operations - the list of operations for this patch

See Also:

JsonPatchOperation

Method Detail

fromJson

public static JsonPatch fromJson(com.fasterxml.jackson.databind.JsonNode node)
                          throws java.io.IOException

Static factory method to build a JSON Patch out of a JSON representation

Parameters:

node - the JSON representation of the generated JSON Patch

Returns:

a JSON Patch

Throws:

java.io.IOException - input is not a valid JSON patch

java.lang.NullPointerException - input is null

apply

public com.fasterxml.jackson.databind.JsonNode apply(com.fasterxml.jackson.databind.JsonNode node)
                                              throws JsonPatchException

Apply this patch to a JSON value

Specified by:

apply in interface Patch

Parameters:

node - the value to apply the patch to

Returns:

the patched JSON value

Throws:

JsonPatchException - failed to apply patch

java.lang.NullPointerException - input is null

getOperations

public final java.util.List<JsonPatchOperation> getOperations()

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

serialize

public void serialize(com.fasterxml.jackson.core.JsonGenerator jgen,
                      com.fasterxml.jackson.databind.SerializerProvider provider)
               throws java.io.IOException

Specified by:

serialize in interface com.fasterxml.jackson.databind.JsonSerializable

Throws:

java.io.IOException

serializeWithType

public void serializeWithType(com.fasterxml.jackson.core.JsonGenerator jgen,
                              com.fasterxml.jackson.databind.SerializerProvider provider,
                              com.fasterxml.jackson.databind.jsontype.TypeSerializer typeSer)
                       throws java.io.IOException

Specified by:

serializeWithType in interface com.fasterxml.jackson.databind.JsonSerializable

Throws:

java.io.IOException