Java 8 LocalDate mapping with mybatis

Question

I am using java.time.LocalDate (Java 8) to represent some of the member fields in a Java class.

class Test{
    private LocalDate startDate;
    private LocalDate endDate;
    //other fields
    
    //getters and setters 
}

I am also using mybatis, to interact with my database.

On retrieving some data from the DB, all other fields get populated properly, but the startDate and endDate fields end up as null.

If ,however, I use java.util.Date, as in,

 private Date startDate;
 private Date endDate;

I get the proper values retrieved in these two fields (startDate and endDate) when I declare them as java.util.Date.

Is it because mybatis does not currently have a mappping of 'Timestamp'(SQL Server) to java.time ?

How should I go about using java.time.LocalDate to map with MyBatis ?

Answer 1

Look here: https://github.com/mybatis/typehandlers-jsr310

If you are using mybatis version 3.4 or later, you can simply add this artifact on your classpath and MyBatis will automatically register the provided type handlers.

<dependency>
  <groupId>org.mybatis</groupId>
  <artifactId>mybatis-typehandlers-jsr310</artifactId>
  <version>1.0.0</version>
</dependency>

If you are using an older version you need to register the type handlers manually.

<typeHandlers>
  <typeHandler handler="org.apache.ibatis.type.InstantTypeHandler" />
  <typeHandler handler="org.apache.ibatis.type.LocalDateTimeTypeHandler" />
  <typeHandler handler="org.apache.ibatis.type.LocalDateTypeHandler" />
  <typeHandler handler="org.apache.ibatis.type.LocalTimeTypeHandler" />
  <typeHandler handler="org.apache.ibatis.type.OffsetDateTimeTypeHandler" />
  <typeHandler handler="org.apache.ibatis.type.OffsetTimeTypeHandler" />
  <typeHandler handler="org.apache.ibatis.type.ZonedDateTimeTypeHandler" />
</typeHandlers>

UPD:

Type handlers for "JSR 310: Date and Time API" has been merged into mybatis core since 3.4.5.(See #974)