cgi / mybatis-jackson

MyBatis JSON support via Jackson library

JSON support for Mybatis 3.x using Jackson 2.6.x

Provide support for JSON like field types in any Database. I'm developed this handler with PostgreSql in mind, but it looks like it can be used with any other database even without JSON support.

Artifact does not include direct jackson dependencies - it is up to you to add them into your project. Looks like you can use any Jackson version compatible with API version >= 2.6.0.

API javadoc

##How does it work Because JDBC does not support JSON types, it transfer JSON to/from database as a string. It serialize JSON to string on save and deserialize from string on read. This feature means that we are really do not care if our DB can support JSON or not.

There are 2 handlers available:

• TreeNodeTypeHandler - work only with ArrayNode and ObjectNode only via TreeNode interface
• JsonNodeValueTypeHandler - value wrapper around JsonNode

###Lazy reading Type handler returns TreeNode wrapper that actually does not parse JSON from string. It is waiting for you to call any of its methods - only then it will read JSON into structure. But this approach may lead to unexpected runtime exception in a case if your database will return invalid JSON string.

##Add to your project You can add this artifact to your project using JitPack.
All versions list, instructions for gradle, maven, ivy etc. can be found by link above.

To get latest commit use -SNAPSHOT instead version number.

Configure

In result map configuration you should use:

• javaType="com.fasterxml.jackson.core.TreeNode"
• javaType="com.fasterxml.jackson.databind.JsonNode"

You should not configure anything if you want to use TreeNode types as arguments in your mapper functions, but keep in mind that handler only expect objects of type ArrayNode or ObjectNode for TreeNodeTypeHandler. And JsonNode for JsonNodeValueTypeHandler.

Mybatis config

<!-- mybatis-config.xml -->
<typeHandlers>
  <typeHandler handler="com.github.javaplugs.mybatis.TreeNodeTypeHandler"/>
  <typeHandler handler="com.github.javaplugs.mybatis.JsonNodeValueTypeHandler"/>
</typeHandlers>

Or you can use package search

<!-- mybatis-config.xml -->
<typeHandlers>
  <package name="com.github.javaplugs.mybatis"/>
</typeHandlers>

Mybatis via Spring

<bean id="SomeId" class="org.mybatis.spring.SqlSessionFactoryBean">
    <!-- your configuration -->
    <property name="typeHandlersPackage" value="com.github.javaplugs.mybatis" />
</bean>