Java 8 introduced a new Date and Time API that brought significant improvements over the old java.util.Date and java.util.Calendar classes. However, when working with Jackson, we might encounter an issue where Java 8 date/time types are not supported by default. This error can be resolved by following a few simple steps.
Step 1: Update Jackson Version
We have to make sure that we are using a Jackson version that supports Java 8 date/time types. If not we need to update our Jackson libraries to a version that is compatible with Java 8. We can check the official Jackson GitHub repository for the latest releases.
<dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> <version>2.15.3</version> <!-- Use the latest version --> </dependency>
If you are using Spring Boot then this dependency should’ve been included automatically.
Step 2: Add Java 8 Module
In newer Jackson versions, the support for Java 8 date/time types is provided by a separate module called
jackson-datatype-jsr310. We need to include this module in our project’s dependencies.
<dependency> <groupId>com.fasterxml.jackson.datatype</groupId> <artifactId>jackson-datatype-jsr310</artifactId> <version>2.15.3</version> <!-- Use the same version as jackson-databind --> </dependency>
Step 3: Register the Module
After adding the
jackson-datatype-jsr310 module, we need to register it with our Jackson ObjectMapper. This can be done in our application’s configuration or initialization code.
ObjectMapper objectMapper = new ObjectMapper(); objectMapper.registerModule(new JavaTimeModule());
Step 4: Handle Serialization and Deserialization
Now that we have registered the Java 8 module, Jackson should be able to handle Java 8 date/time types during serialization and deserialization. Ensure that our date/time fields in our Java classes are of the appropriate types (e.g.,
LocalDateTime), and Jackson will handle the conversion correctly.
ObjectMapper objectMapper = new ObjectMapper(); objectMapper.registerModule(new JavaTimeModule()); //Deserializing JSON object to Java Object MyObject myObj = objectMapper.readValue(json, MyObject.class);
By updating our Jackson dependencies, adding the Java 8 module, and registering it with the ObjectMapper, we should successfully resolve the “Jackson Error: Java 8 date/time type not supported by default” issue in our Java application. This ensures smooth handling of Java 8 date/time types during JSON serialization and deserialization processes.
Frequently Asked Questions (FAQs)
What is the cause of the “Jackson Error: Java 8 date/time type not supported by default”?
The error occurs when working with Jackson and Java 8 date/time types due to the lack of native support for these types in older versions of Jackson. To resolve this issue, it’s essential to update your Jackson dependencies and include the necessary modules for Java 8 date/time support.
How can I update my Jackson version?
To update your Jackson version, modify your project’s Maven or Gradle dependencies to include the latest version of the
jackson-databind library. You can find the latest version on the official Jackson GitHub repository and update your project configuration accordingly.
What is the purpose of the
jackson-datatype-jsr310 module provides support for Java 8 date/time types in Jackson. By including this module in your project’s dependencies and registering it with the ObjectMapper, you enable Jackson to handle serialization and deserialization of Java 8 date/time objects correctly.
How do I register the
jackson-datatype-jsr310 module with the ObjectMapper?
To register the
jackson-datatype-jsr310 module, create an instance of
JavaTimeModule and register it with your ObjectMapper. This can be done in your application’s configuration or initialization code, ensuring that Jackson recognizes and supports Java 8 date/time types. You can see an example above Register the Module section.
Do I need to make changes to my existing date/time fields in Java classes?
Yes, to resolve the error, ensure that your date/time fields in Java classes are of the appropriate Java 8 types, such as
LocalDateTime. Jackson relies on the type information to handle the serialization and deserialization of these objects correctly.