by eclipse

eclipse /californium

CoAP/DTLS Java Implementation

479 Stars 278 Forks Last release: 16 days ago (2.4.1) Other 2.2K Commits 46 Releases

Available items

No Items, yet!

The developer of this repository has not created any items for sale yet. Need a bug fixed? Help with integration? A different license? Create a request here:

Californium logo

Eclipse Californium is a Java implementation of RFC7252 - Constrained Application Protocol for IoT Cloud services. Thus, the focus is on scalability and usability instead of resource-efficiency like for embedded devices. Yet Californium is also suitable for embedded JVMs.

More information can be found at and

Build using Maven

You need to have a working maven installation to build Californium. Then simply run the following from the project's root directory:

$ mvn clean install

Executable JARs of the examples with all dependencies can be found in the


The build-process is tested for jdk 7, jdk 8 and jdk 11. For jdk 7 the revapi maven-plugin is disabled, it requires at least java 8.

To generate the javadocs, add "-DcreateJavadoc=true" to the command line and set the

$ mvn clean install -DcreateJavadoc=true

Californium 2.x can be used with java 7 or newer. If you want to build it with a jdk 7, but use also plugins which are only supported for newer jdks, the toolchain plugin could be used. That requires a toolchains configuration in "toolchains.xml" in your maven ".m2" folder


To use the jdk7 toolchain, add "-DuseToolchain=true" to the command line.

$ mvn clean install -DuseToolchain=true

To use the jdk7 toolchain and create javadocs, add "-DuseToolchainJavadoc=true" to the command line (

is not required).
$ mvn clean install -DuseToolchainJavadoc=true

Using Californium in Maven Projects

We are publishing Californium's artifacts for milestones and releases to Maven Central. To use the latest released version as a library in your projects, add the following dependency to your

(without the dots):
Current Builds

You can also be bold and try out the most recent build from

. However, we are not publishing those to Maven Central but to Californium's project repository at Eclipse only. You will therefore need to add the Eclipse Repository to your
      Californium Repository

You can then simply depend on



The project can be easily imported into a recent version of the Eclipse IDE. Make sure to have the following before importing the Californium (Cf) projects:

Then choose [Import... » Maven » Existing Maven Projects] to import

into Eclipse.


The project can also be imported to IntelliJ as follows:

In IntelliJ, choose [File.. » Open] then select the location of the cloned repository in your filesystem. IntelliJ will then automatically import all projects and resolve required Maven dependencies.

Interop Server

A test server is running at coap:// It is an instance of the cf-plugtest-server from the demo-apps. The root resource responds with its current version. More information can be found at

Another interop server with a different implementation can be found at coap:// More information can be found at


A bug, an idea, an issue? Join the Mailing list or create an issue here on GitHub.


Please check out our contribution guidelines

We use cookies. If you continue to browse the site, you agree to the use of cookies. For more information on our use of cookies please see our Privacy Policy.