Skip to content
Go to file

Latest commit


Git stats


Failed to load latest commit information.
Latest commit message
Commit time


Joda-Convert is a small, highly-focussed library, tackling a problem that the JDK should solve - providing round-trip conversion between Objects and Strings. It is not intended to tackle the wider problem of Object to Object transformation.

// conversion to String
String str = StringConvert.INSTANCE.convertToString(foo);

// conversion from String
Foo bar = StringConvert.INSTANCE.convertFromString(Foo.class, str);

Joda-Convert supports two mechanisms of extending the list of supported conversions. The first is to write your own converter implementing an interface. The second is to use annotations.

The ability of Joda-Convert to use annotations to define the conversion methods is a key difference from other projects. For example, most value classes, like Currency or TimeZone, already have methods to convert to and from a standard format String. Consider a Distance class annotated with FromString and ToString:

public class Distance {

  public static Distance parse(String str) { ... }

  public String getStandardOutput() { ... }


As shown, the two methods may have any name. They must simply fulfil the required method signatures for conversion. The FromString annotation may also be applied to a constructor.

When Joda-Convert is asked to convert between an object and a String, if there is no registered converter then the annotations are checked. If they are found, then the methods are called by reflection.

Joda-Convert is licensed under the business-friendly Apache 2.0 licence.


Various documentation is available:


Release 2.2.1 is the current latest release. This release is considered stable and worthy of the 2.x tag. The v2.x releases are compatible with v1.x releases, with the exception that the direct Guava dependency is removed. It depends on Java SE 6 or later.

Available in the Maven Central repository

Tidelift dependency check

For enterprise

Available as part of the Tidelift Subscription.

Joda and the maintainers of thousands of other packages are working with Tidelift to deliver one enterprise subscription that covers all of the open source you use.

If you want the flexibility of open source and the confidence of commercial-grade software, this is for you.

Learn more


Please use Stack Overflow for general usage questions. GitHub issues and pull requests should be used when you want to help advance the project.

Any donations to support the project are accepted via OpenCollective.

To report a security vulnerability, please use the Tidelift security contact. Tidelift will coordinate the fix and disclosure.

Release process

  • Update version (,, changes.xml)
  • Commit and push
  • mvn clean release:clean release:prepare release:perform
  • git fetch
  • Website will be built and released by GitHub Actions
You can’t perform that action at this time.