Maven Wagon provides a layer of abstraction over the underlying transport protocols to transfer resources or artifacts to and from Maven repositories. At the time of writing this book, the unified API provided by Maven Wagon has implementations for seven transports. The following figure shows the layered architecture of Maven Wagon:
Due to the decoupled architecture, Maven does not have a hard dependency on the communication protocols supported by the repository. It can be over HTTP, FTP, SSH, WebDAV, or any other custom protocol.
Note
More details about Maven Wagon can be found at http://maven.apache.org/wagon/.
From Maven 3.0.4 onwards, Wagon HTTP(S) transport is based on Apache HTTP client 4.1.2. This also added the HTTP connection pooling support. By default, the connection pool size is 20 per destination. Wagon HTTP transport can be further tuned via settings.xml.
Maven artifact repositories can be defined in the application POM and will also inherit from...