ebrevdo/jackson-core

Core part of Jackson that defines Streaming API as well as basic shared abstractions

Overview

This project contains core low-level incremental ("streaming") parser and generator abstractions used by Jackson Data Processor. It also includes the default implementation of handler types (parser, generator) that handle JSON format. The core abstractions are not JSON specific, although naming does contain 'JSON' in many places, due to historical reasons. Only packages that specifically contain word 'json' are JSON-specific.

This package is the base on which Jackson data-binding package builds on.

Alternate data format implementations (like Smile (binary JSON), XML and CSV) also build on this base package, implementing the core interfaces, making it possible to use standard data-binding package regardless of underlying data format.

Project contains versions 2.0 and above: source code for earlier (1.x) versions is available from Codehaus SVN repository.

Differences from Jackson 1.x

Project contains versions 2.0 and above: source code for earlier (1.x) versions is available from Codehaus SVN repository

Note that the main differences compared to 1.0 core jar are:

• Maven build instead of Ant
• Annotations carved out to a separate package (that this package depends on)
• Java package is now com.fasterxml.jackson.core (instead of org.codehaus.jackson)

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Get it!

Maven

Functionality of this package is contained in Java package com.fasterxml.jackson.core.

To use the package, you need to use following Maven dependency:

<dependency>
  <groupId>com.fasterxml.jackson.core</groupId>
  <artifactId>jackson-core</artifactId>
  <version>2.2.0</version>
</dependency>

or download jars from Maven repository or Download page. Core jar is a functional OSGi bundle, with proper import/export declarations.

Package has no external dependencies, except for testing (which uses JUnit).

Non-Maven

For non-Maven use cases, you download jars from Central Maven repository or Download page.

Core jar is also a functional OSGi bundle, with proper import/export declarations, so it can be use on OSGi container as is.

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Use it!

General

Usage typically starts with creation of a reusable (and thread-safe, once configured) JsonFactory instance:

JsonFactory factory = new JsonFactory();
// configure, if necessary:
factory.enable(JsonParser.Feature.ALLOW_COMMENTS);

Alternatively, you have a ObjectMapper (from Jackson Databind package) handy; if so, you can do:

JsonFactory factory = objectMapper.getJsonFactory();

More information can be found from Streaming API at Jackson Wiki.

Usage, simple reading

All reading is by using JsonParser (or its sub-classes, in case of data formats other than JSON), instance of which is constructed by JsonFactory.

An example can be found from Reading and Writing Event Streams

Usage, simple writing

All writing is by using JsonGenerator (or its sub-classes, in case of data formats other than JSON), instance of which is constructed by JsonFactory:

An example can be found from Reading and Writing Event Streams

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Further reading

• Documentation has other project documentation
• Jackson Project Home