Package org.json.stream

A streaming parser implementation and related tools for JSON.

See: Description

Interface Summary

Interface	Description
LimitFilter	Filtering for structures during a parse.
StructureCollector<OA,AA,OR,AR>	Allows JSONLimitBuilder to parameterize the creation and population of object and array structures, null values, and creation of a "finished" result type.

Class Summary

Class	Description
BuilderLimits	Builder limits, based on similar limits used in some XML parsers.
CollectionCollector	Structure collector that creates HashMap, ArrayList, and null instances.
JSONCollector	Structure collector that creates JSONObject, JSONArray, and JSONObject.NULL instances.
JSONLexer	A JSONLexer takes a source stream and extracts characters and tokens from it.
JSONLimitBuilder	Builds a JSON object model using events supplied from JSONLimitStreamReader, using secure principles derived from XML parsers.
JSONLimitStreamReader	Reads a JSON document as a stream of JSON events, using secure principles derived from XML parsers.
JSONObjectBuilder	Builds a JSON object model using events supplied from JSONStreamReader.
JSONStreamReader	Reads a JSON document as a stream of JSON events.

Enum Summary

Enum	Description
JSONLexer.Token	Tokens that can be identified with at most one character lookahead.
JSONStreamReader.ParseState	States of the internal state machine.

Package org.json.stream Description

A streaming parser implementation and related tools for JSON. Implements a streaming pull parser with the following components:

Stream Reader

JSONStreamReader provides an implementation of a streaming pull-parser, similar to JSR 353 for JavaEE, or the Jackson JSON parser. The stream reader reads strictly conforming JSON data, and has "hooks" to allow reading of long data, such as base64-encoded data within a JSON string.

This reader should be considered when the source JSON data is from a known safe origin.

Object Builder

JSONObjectBuilder is a builder of JSONObject and JSONArray structures built on top of the stream reader. The implementation ends up simpler than JSONTokener, mainly because a lot of the heavy lifting is done in the stream reader.

Limit Stream Reader

JSONLimitStreamReader provides a stream reader that is better at dealing with JSON data from untrusted origins, such as unknown internet connections. It is build with deliberate boundaries that avoid memory exhaustion and other data storage limits, for the purposes of denial-of-service attacks.

Limit Object Builder

JSONLimitBuilder is built on top of the limit stream reader above, it limits its use of the runtime stack to avoid stack smashing attempts from untrusted JSON sources.

This parser may be slower than the other object builder above -- <20% in informal testing -- due to its use of trampolining for creating nested structures.

Builder Limits

BuilderLimits limits that are applied to a limit stream reader and limit object builder. These are based on similar limits found in secure XML processing parsers.

Limit Filter

LimitFilter provides an easy interface for accepting or rejecting particular structures during a JSON parse process.

Structure Collector

StructureCollector parameterizes the type of structures to be created by the object builders. Two provided collectors are:

• JSONCollector, which creates JSONObject and JSONArray objects; and
• CollectionCollector, which creates HashMap and ArrayList objects.