aismessages

Introduction

AISmessages is a Java-based light-weight, zero-dependency, and ultra-efficient message decoder for maritime
navigation and safety messages compliant with ITU 1371 (NMEA armoured AIS messages).

It exhibits lazy decoding and fully decodes tens of thousands of NMEA armoured AIS messages per second per CPU
core on an Intel i7-based laptop.

For more than 10 years AISmessages has been used in production in many systems and solutions all over the world.

If you are new to AIS you can read a short introduction to it on my blog.

Other AIS projects

In addition to AISmessages, its sister project AISutils offers higher level functionality such as Tracking and Filtering using AISmessages as a foundation.

There is also AIScli which allows conversion, filtering, etc. of AIS messages from the command line. AIScli
is built on top of both AISmessages and AISutils.

Applications, demos, and talks

There are several demos, intros, and public appearances of AISmessages; like for instance:

1. How AISmessages is utilized by OpenRemote, Inc. for the Safe Waterways project in the Beatrix Canal, NL, as explained in this Youtube video:
   
   

2. How AISmessages is used in Dakosy’s PRISE system to optimise sequencing and arrival of mega-ships on the river Elbe and at the Port of Hamburg (read reference page)

3. How AISmessages can be used to “decode the air around you” as Bert Jan Schrijver (@bjschrijver) of JPoint talks about

   1. at DEVOXX BE 2015 (watch conference video)
   2. at DEVOXX UK 2015 (watch conference video)

4. A live demo of AISmessages is available on http://ais.tbsalling.dk.

5. See a simple demo applications in the source code in the dk.tbsalling.aismessages.demo package (view via
   Github).

6. AISMessages is used by Pronto, which enables the Port of Rotterdam to optimize port calls and vessel opterations. Watch it on Youtube:
   
   

7. AISMessages is used by Shiptracker (https://shiptracker.portofrotterdam.com), which enables Port of Rotterdam to show its customers the current position and ETA of ships scheduled to arrive in the port.
   
   

Programmatic usage

Programmatically the starting point is the AISStreamReader. It takes an InputStream (feeding
NMEA data), and a consumer of AISMessages which as called back every time an AIS message is decoded. So,
if you have an InputStream serving data like this:

    !AIVDM,1,1,,A,15Mv5v?P00IS0J`A86KTROvN0<5k,0*12
    !AIVDM,1,1,,A,15Mwd<PP00ISfGpA7jBr??vP0<3:,0*04
    !AIVDM,2,1,4,B,55MwW7P00001L@?;GS0<51B08Thj0TdpE800000P0hD556IE07RlSm6P0000,0*0B
    !AIVDM,2,2,4,B,00000000000,2*23
    !AIVDM,1,1,,A,15N7th0P00ISsi4A5I?:fgvP2<40,0*06
    !AIVDM,1,1,,A,15NIEcP000ISrjPA8tEIBq<P089=,0*63
    !AIVDM,1,1,,B,15MuS0PP00IS00HA8gEtSgvN0<3U,0*61
    \c:1609841515,s:r3669961*78\!AIVDM,1,1,,A,13ukmN7@0<0pRcHPTkn4P33f0000,0*58
    \c:1609841515,s:r3669961,g:1-2-1234*0E\!AIVDM,1,1,,A,13ukmN7@0<0pRcHPTkn4P33f0000,0*58

then you can decode it into Java POJO’s of type AISMessage like this:

    public class DemoApp {

        public static void main(String[] args) throws IOException {

           InputStream inputStream = ...

           AISInputStreamReader streamReader
                = new AISInputStreamReader(
                    inputStream,
                    aisMessage -> System.out.println(aisMessage))
           );

           streamReader.run();
	    }

    }

The second argument to the AISInputStreamReader constructor (aisMessage -> System.out.println(aisMessage)) is a
Consumer<? super AISMessage> which consumes decoded AIS messages in the form of AISMessage objects.

AISMessage has several subclasses - one for each type of AIS message, which can be decoded. For instance an AIS
message of type 5 “Static and voyage related data” are represented by objects of class ShipAndVoyageData as shown here
in fragments:

public class ShipAndVoyageData extends AISMessage implements StaticDataReport {
   ...
   public IMO getImo() { ... }
   public String getCallsign() { ... }
   public String getShipName() { ... }
   public ShipType getShipType() { ... }
   public Integer getToBow() { ... }
   public Integer getToStern() { ... }
   public Integer getToStarboard() { ... }
   public Integer getToPort() { ... }
   ...
}

Obtaining AISmessages

You do not need to compile AISmessages yourself. It is available in Maven Central. So if you are using Maven, all you
need to do is add these lines to your pom.xml:

...
<dependency>
    <groupId>dk.tbsalling</groupId>
    <artifactId>aismessages</artifactId>
    <version>3.4.0</version>
</dependency>
...

License

AISmessages is released under the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA
4.0)
license - which means that it is free for non-commercial use. For full license details see the
LICENSE-full file or read the summary.

To obtain a commercial license and/or commercial support contact
Thomas Borg Salling - [email protected].