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Supplemental information for JOSM -- the Java OpenStreetMap Editor

            I. Install & Launch

Installation notes
To run JOSM, you need:

* The JOSM .jar file, e.g., josm-tested.jar or josm-latest.jar
* Java Runtime Environment (JRE) 8, or later.

How to get Java Runtime Environment
You need JRE Version 8, or later.

Microsoft Windows and Apple macOS users should visit one of:
and download the latest Java executable for their system.

Linux users should visit
There is a Linux binary installer, which you must execute from a console, or
use the mechanism of your distribution's packaging system.

How to launch
Microsoft Windows users launch by double-clicking on the .jar file.
If this does not work, open a command shell and type
"java -jar josm-latest.jar"  in the directory that holds the file. (Please
replace josm-latest.jar with the name of your .jar file, if you aren't using
the latest version.)

Under Linux, open a shell, go to the file directory and type
"java -jar josm-latest.jar" to launch. If this does not work, try to set
your JAVA_HOME variable to the java executable location (the root location,
not the bin).

macOS users just click on the .jar file icon.

            II. Development

How to get the source code
Download it directly from the subversion at To use the command line subversion
client, type

svn co josm

Files & directories
This is an overview of the files and directories in the JOSM code repository:
- build.xml                 ant build file (standard way to create a JOSM binary)
- CONTRIBUTION              list of major code contributors
- gpl-2.0.txt, gpl-3.0.txt  full text of the GNU General Public License
- LICENSE                   the JOSM license terms
- native/                   OS-specific files
  - linux/                  files useful for Linux distributions, including Appdata files, .desktop
                            files, Debian/Ubuntu scripts, man pages, icons, etc.
  - macosx/                 files needed to create the MacOS package
  - windows/                files needed to create the Windows installer
  - josm.jnlp               Java Web Start launcher file (used on the website for the tested version)
  - josm-latest.jnlp        Java Web Start launcher file (used on the website for the latest version)
- nodist/                   files not included in JOSM binary
  - data/                   data files that are useful for development, but not distributed
    - exif-direction-example.jpg
                            sample image, that contains direction information in the EXIF header
                            (keys: Exif.GPSInfo.GPSImgDirectionRef, Exif.GPSInfo.GPSImgDirection)
    - filterTests.osm       used for unit testing of the filter feature
                            (see test/unit/org/openstreetmap/josm/data/osm/
    - Join_Areas_Tests.osm  some examples to test the 'join areas' feature
    - *.*                   various other data files used for unit testing and as reference file
    - projection/           projection files
      - *.gsb               NTv2 grid files for projection support, downloaded by the
                            client on demand (see CONTRIBUTION)
      - CHENyx06-Distribution.pdf
                            archive of terms of use for the CHENyx06.gsb file
      - epsg                EPSG data file, taken from the proj.4 project
      - esri                ESRI data file, taken from the proj.4 project
      - josm-epsg           customizations to the epsg file, used together with the epsg file
                            to generate data/projection/custom-epsg
      - projection-reference-data.csv
                            reference data for projection tests
                            (see test/unit/org/openstreetmap/josm/data/projection/
      - projection-regression-test-data.csv
                            regression data for projection tests
                            (see test/unit/org/openstreetmap/josm/data/projection/
    - trans/*.lang          translation data for files that are not distributed, but used
                            by the server for localization of the services;
                            currently contains plugin descriptions in order to include translations
                            in the downloaded plugin list
  - images/                 images, which are not for distribution, but may be useful later (e.g. high
                            resolution and vector versions)
  - styles/                 files needed for map style maintenance
    - potlatch2/README      infos on how to update the Potlatch 2 style from upstream sources
- README                    this file
- resources/                resource files that will be included in the JOSM jar file
  - data/                   data files that will be included in the JOSM jar file
    - fonts/                font files used for map rendering
    - gpx/                  different color gradients for gpx drawing
    - projection/           projection files
      - custom-epsg         list of projection definitions, auto-generated file created by ant task 'epsg'
    - security/*.pem        certificates that we like to accept for TLS connections, but are missing in the
                            default Java certificate store
    - validator/            data files used by the JOSM validator
      - *.cfg               files designed for the old tagchecker, still in use
      - *.mapcss            default validation rules for the MapCSS-based tagchecker
    - boundaries.osm        OSM file containing boundary data for the states of the earth, including
                            data for right and left-hand traffic
    - defaultpresets.xml    data file for the core tagging presets
    - help-browser.css      CSS file for the help sites (HTML content is downloaded from the website
                            on demand, but displayed inside the programm in a Java web browser component.)
    - *.lang                translation data
    - *.xsd                 xml schema files for validation of configuration files
  - images/                 images distributed with the JOSM binary
    - icons                 images for the Potlatch 2 style
    - presets               images for the main mappaint style and the internal presets
  - styles/                 map styles included in JOSM
- scripts/                  various scripts used by JOSM developers
                            called from the ant build file to combine the files epsg and josm-epsg
                            to create the custom-epsg file for distribution
  -             tool to find all used icons and allows deleting unused icons
                            searches also for images with incompatible svg code
  - optimize-images         short script to decrease size of PNG images
  -            developer tool to replace "@since xxx" in Javadoc by the upcoming revision number
                            script to compare and analyse the differences of the editor layer index and the
                            JOSM imagery list (see
  -     extracts tag information for the taginfo project
- src/                      the source code of the application
- start.html                HTML page to run the applet version of JOSM
- test/                     automated software tests
    - data/                 resources used for some tests
    - functional/           functional tests (source code)
    - lib/                  libraries needed for (some of) the tests, including JUnit
    - performance/          performance tests (source code)
    - unit/                 unit tests (source code)
- tools/                    libraries, tools and configuration files that help in the development process
    - checkstyle/           libs and config files for checkstyle (automatically detects code style
                            problems in source code); can be launched as an ant target in build.xml
    - eclipse/              preconfigured Eclipse configuration files
    - ivy/                  Apache Ivy binary, configuration file, and downloaded dependencies 
    - jacocoant.jar         used to include coverage data into JUnit test reports
    - japicc/               used to generate a compatibility report between optimized jar and normal one
    - netbeans/             preconfigured Netbeans project
    - pmd/                  config files for PMD (source code analyzer, finds common programming flaws)
    - spotbugs/             libs and config files for spotbugs (automatically detects common bugs and potential
                            problems in source code); can be launched as an ant target in build.xml

Third party libraries
There are some third party libraries which are directly included in the source code tree, in particular:

* jmapviewer: Java component to browse a TMS map
    src/org/openstreetmap/gui (svn external)
* Apache commons compress: Support for bzip2 compression when opening files
* Apache commons validator: Improved validator routines
* SVG Salamander: Support for SVG image format
* Metadata Extractor: Read EXIF Metadata of photos
* Signpost: OAuth library
* MultiSplitPane: Small lib for GUI layout management
* swinghelper: Class CheckThreadViolationRepaintManager to find EDT violations
* xz extractor
* OpeningHoursParser (MIT license)