com.github.fge.jsonschema.ref

Class JsonPointer

java.lang.Object

com.github.fge.jsonschema.ref.JsonFragment

com.github.fge.jsonschema.ref.JsonPointer

All Implemented Interfaces:

Comparable<JsonFragment>

public final class JsonPointer
extends JsonFragment

Implementation of IETF JSON Pointer draft, version 8

JSON Pointer is an IETF draft defining a way to address paths within JSON documents. Paths apply to containers, ie arrays or nodes. For objects, path elements are member names. For arrays, they are indices in the array (starting from 0).

The general syntax is #/path/elements/here. A path element is referred to as a "reference token" in the specification.

The difficulty solved by JSON Pointer is that any JSON String is valid as an object member name. These are all valid object member names, and all of them can be addressed by using JSON Pointer:

• "" -- the empty string;
• "/";
• "0";
• "-1";
• ".", "..", "../..".

The latter example is the reason why a JSON Pointer is always absolute.

All instances of this class are thread safe and immutable.

Field Summary

Fields inherited from class com.github.fge.jsonschema.ref.JsonFragment

asString

Constructor Summary

Constructors

Constructor and Description
JsonPointer(String input) Constructor

Method Summary

Methods

Modifier and Type	Method and Description
JsonPointer	append(int index) Append an array index to this pointer.
JsonPointer	append(String element) Append a path element to this pointer.
JsonNode	resolve(JsonNode node) Resolve this fragment against a given node

Methods inherited from class com.github.fge.jsonschema.ref.JsonFragment

compareTo, equals, fromFragment, hashCode, isEmpty, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

JsonPointer

public JsonPointer(String input)
            throws JsonSchemaException

Constructor

Parameters:

input - The input string, guaranteed not to be JSON encoded

Throws:

JsonSchemaException - Illegal JSON Pointer

Method Detail

append

public JsonPointer append(String element)

Append a path element to this pointer. Returns a new instance.

Parameters:

element - the element to append

Returns:

a new instance with the element appended

append

public JsonPointer append(int index)

Append an array index to this pointer. Returns a new instance.

Note that the index validity is NOT checked for (ie, you can append -1 if you want to -- don't do that)

Parameters:

index - the index to add

Returns:

a new instance with the index appended

resolve

public JsonNode resolve(JsonNode node)

Description copied from class: JsonFragment

Resolve this fragment against a given node

Specified by:

resolve in class JsonFragment

Parameters:

node - the node

Returns:

the result node (MissingNode if the fragment is not found)