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= CAN



A CAN transport is a special category of transport which can bring CAN frame data to various drivers.
All of these transports are meant to follow basic CAN frame data semantics.

Each CAN transport must provide a `CANFrameBuilder` interface realization.
This builder can be used by drivers which implement application layer protocols on top of CAN bus.
The builder allow constructing requests which should be passed to the bus operations.

Note this API is available since Apache PLC4X 0.9.

[cols="2,2a,5a"]
|===
|Name |Value |Description

|Code
|not available
|This transport ships only additional API on top of existing Apache PLC4X Transport API.

|Name
2+|CAN

|Maven Dependency
2+|
[subs=attributes+]
----
<dependency>
  <groupId>org.apache.plc4x</groupId>
  <artifactId>plc4j-transports-can</artifactId>
  <version>{current-project-version}</version>
</dependency>
----

|Options:
2+|*none*, an abstract transport
|===

Main purpose of this transport is basic unification of various CAN bus APIs.
There is no unified way to access CAN (beside SocketCAN for linux) across multiple platforms.
We brought this simplistic facade-alike API to serve very basic project needs.
Its main purpose is to let transport implementer bridge with actual transport or another library.
With as little effort as possible.

Major advantage of CAN transport facade is possibility to implement application layer protocols in a fully portable way.
This flexibility is not guaranteed with SocketCAN alone.

The CAN transport responsibility is to bring CAN data to driver implementer.
This API does not enforce, require or promote a low level bus operations.
In this regard, these operations can be made by library available for specific CAN adapter in use.

== Developer notes

Usage of CAN transport APIs is recommended for portability reasons.
Please have a look on xref:protocols/can.adoc[CAN] describe usage of CAN driver adapter with CAN transport facade.

== Compatible CAN transports

- xref:transports/socketcan.adoc[SocketCAN]