HafenCity Universität Hamburg, Department Geomatik
OpenJUMP Tutorial
(basics)
Based on German Version 3/2006
by Uwe Dalluege
HCU Hamburg
Dept. Geomatik
OpenJUMP tutorial (basics)
author: translation:
Uwe Dalluege Stefan Steiniger
HafenCity Universität Hamburg Jump Pilot Project
Department Geomatik
Hebebrandstr. 1
22297 Hamburg
E-Mail: uwe.dalluege@rzcn.haw-hamburg.de jump-pilot-devel@lists.sourceforge.net
terms of usage:
This text is free; you can redistribute it and/or modify it under the terms of GNU Free Documentation
License (http://www.gnu.org/licenses/fdl.txt).
With support of (in alphabetical order):
Dipl.-Ing. Jürgen Faber, HCU Hamburg
Dipl.-Ing. Kay Zobel, HCU Hamburg
Dipl.-Ing. Stefan Steiniger, University of Zurich
2 HCU Hamburg, Dept. Geomatik
Content
1 Before The Journey Begins .................................................................................................................. 4
2 User Interface of OpenJUMP ................................................................................................................ 5
2.1 The Toolbar ...................................................................................................................................... 6
3 Data ........................................................................................................................................................ 7
3.1 Geometry data .................................................................................................................................. 7
3.2 Attribute values ................................................................................................................................. 7
4 The Editing Toolbox .............................................................................................................................. 8
4.1 Editing Toolbox ................................................................................................................................. 9
4.1.1 Options (Snap/Grid) ................................................................................................................. 9
4.2 Features ......................................................................................................................................... 10
4.2.1 Drawing Features ................................................................................................................... 10
4.2.1.1 Drawing an area (Polygon): ........................................................................................... 10
4.2.1.2 Drawing a ,,hole" in a polygon: ....................................................................................... 10
4.2.2 Combining/Grouping Features (Geometry Collection) ........................................................... 11
4.2.3 Resolving/Ungrouping Features ............................................................................................. 11
4.2.4 Selecting and Moving Features .............................................................................................. 11
4.3 Editing line points (vertex, vertices) ............................................................................................... 12
4.4 Splitting Lines (LineStrings) ............................................................................................................ 12
5 Editing Layers ...................................................................................................................................... 13
5.1 Layer ............................................................................................................................................... 13
5.1.1 Layer Properties ..................................................................................................................... 13
5.1.2 Saving Layers and Projects ................................................................................................... 15
5.2 WMS-Layer .................................................................................................................................... 16
6 Schema editing ................................................................................................................................... 18
7 Editing Attributes ................................................................................................................................ 19
8 Layer display (Styles) .......................................................................................................................... 20
8.1 Normal Styles (Rendering) ............................................................................................................. 20
8.2 Colour Theming .............................................................................................................................. 21
8.3 Labeling .......................................................................................................................................... 23
8.4 Start- and End Point Display (Decorations) .................................................................................... 24
9 Analysis Tools ..................................................................................................................................... 25
9.1 Buffer .............................................................................................................................................. 25
9.2 Overlay ........................................................................................................................................... 26
9.3 Union .............................................................................................................................................. 27
9.4 Geometry Functions ....................................................................................................................... 28
10 Connection to a PostgreSQL/PostGIS database .......................................................................... 30
10.1 Reading Tables ............................................................................................................................ 30
10.2 Writing Tables .............................................................................................................................. 31
11 Printing ............................................................................................................................................... 32
12 Glossary ............................................................................................................................................. 33
13 Literature References ....................................................................................................................... 37
14 Link Collection ................................................................................................................................... 39
15 Index ................................................................................................................................................... 40
HCU Hamburg, Dept. Geomatik 3
1 OpenJUMP tutorial (basics)
1 Before The Journey Begins
OpenJUMP is a Geographical Information System (GIS), which has been developed originally by the two
Canadian companies Vivid Solutions und Refractions Research under the name JUMP. The name JUMP
is an abbreviation for Unified Mapping Platform. The ,,J" points to the used programming language ,,Java".
,,Open" is for ,,Open Source", which means that the quell code is accessible for everybody. OpenJUMP
underlies the GNU General Public License and is maintained and improved by programmers around the
globe.
The main features of OpenJUMP are:
* vector-based GIS
* underlies the GNU General Public License http://www.gnu.org/licenses/licenses.html#GPL
* is based on Open GIS standards http://www.opengeospatial.org/
* written in Java and open source (accessible programming code)
* can be easily extended by PlugIns
* easy to use editing and analysis functions
* supports several languages (English, French, Portuguese, Spanish, German)
GeoCity in OpenJUMP
4 HCU Hamburg, Dept. Geomatik
User Interface of OpenJUMP 2
2 User Interface of OpenJUMP
After starting OpenJUMP the OpenJUMP Workbench is shown with an empty project window. This window
contains a list of layers and a graphic display, the Layer View, in which the layers are displayed. Layers are
used to display geographic objects (features). A Layer usually contains objects of specific geographic theme
(e.g. water bodies, forest, buildings, soils). A Project contains a collection of all layers.
One can open more than
one project window at the
same time. With the menu
option ,,window" one can
switch between the project
windows. A new project will
be created with
,,File>NewProject..." .
An existing project can be
opened using the menu
command
,,File>OpenProject..." .
After starting OpenJUMP
Note: Every layer has to be saved in a file or database first, if this has been done one can save the project
(see ,,Layer", page 13).
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Workbench Layer ViewProject Window
Layer list toolbar
2 OpenJUMP tutorial (basics)
2.1 The Toolbar
The Toolbar enables to have fast access to functions like zooming, panning, selection or to activate the
graphic editing tools.
Tool Bar
Zooming Panning
Show all data Zoom to selected item
Zoom to fence
Previews view Next view
Change layer visualisation Display attributes (also for modification)
Select items Clear selection
Draw a fence Show feature information
Editing toolbox Measure
Undo Redo
Output Window Fast Zooming
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Data 3
3 Data
An important part of a GIS are the data, consisting usually of geometry data and attribute data. The question
is: How can we add these data to our project.
3.1 Geometry data
There exists several methods to add geometric data to a project:
1. By making some freehand drawings with the graphic editing tools. This is a very simple
method is not very common with out any original to digitize (see ,,The Editing Toolbox",
page 8)
2. By importing data, stored in a specific file format. OpenJUMP supports the following formats:
a) JUMP GML format (.jml), which is a simplified GML-format.
b) GML 2.0 format.
c) WKT (Well Known Text) format.
d) ESRI Shapefile.
Using ,,File>Load Dataset(s) ..."
3. By displaying image raster data, which can be received from a WMS-Server. Here, one can
digitize the data from the images with the editing tools.
4. By loading a database table from PostGIS (only with additional external plugins). Thereby the
data (geometries and attributes) are stored in the object relational database PostgreSQL with
a so called spatial extension PostGIS and are transformed into the OpenJUMP format to
display the data.
5. Note: There exists several external plugins to load raster image data from files (further info
can be obtained from www.openjump.org
3.2 Attribute values
There exists several methods to add attribute data to a project::
1. Through direct input in OpenJUMP. Therefore the geometry data must exist already (see
also under Schema editing p. 18)
2. By importing the data from files in a specific format. OpenJUMP supports the following file
formats, which also may contain geometry data:
a) JUMP GML format (.jml), which is a simplified GML-format.
b) GML 2.0 format.
c) ESRI Shapefile (dbf files).
3. By loading a database table from PostGIS (only with additional external plugins).
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4 OpenJUMP tutorial (basics)
4 The Editing Toolbox
In OpenJUMP exists an editing toolbox to create new or modify geometries of geographic objects (features).
One can create and edit the following geometries: points, lines (Linestring) and polygons (Polygon).
The toolbox can be activated with the button from the Tool Bar.
New features can be drawn in a new layer, which can be created by using ,,Layer>Add a new layer". New
features can also be drawn in existing layers, if they are made ,,editable" (see layer mouse menu).
Layer>Add a new layer
A new created layer is the name ,,New" assigned and is set to editable by default. Is a layer editable, then iťs
name is drawn in red. If one selects an editable layer, the mouse the name will be displayed in yellow and
new geometries are drawn in that layer. If Geometries should be modified the layer must be editable as well.
The mouse menu the option ,,Editable" (Right click on layer name) sets the editing status of the selected layer.
After double-left-click on the layer name, the name can be changed.
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The Editing Toolbox 4
4.1 Editing Toolbox
The Editing Toolbox contains tools for modifying and generating new geometries. The most important ones
are:
Editing Toolbox
4.1.1 Options (Snap/Grid)
In the Options window two supporting tools can be set: the Snapping Mode and Grid Display. Default
snapping tolerance is 10 pixels and ,,Snap to vertices".
snapping and grid display options
HCU Hamburg, Dept. Geomatik 9
Rectangle, Polygon, Line and Point drawing tools
Add, delete and move a vertex (line point)
Snap vertices; split lines
Selection and Move tools
4 OpenJUMP tutorial (basics)
4.2 Features
Features are abstracted/generalized objects of the real world. For instance roads are abstracted and displayed
as lines, buildings as polygons and trees as points.
In OpenJUMP every feature consists of a spatial attribute (geometry) and non or several non-spatial attributes
(fields, properties) e.g. road name, owner, tree height.
4.2.1 Drawing Features
Three different features / geometry types can be drawn:
Point , Linestring and Areas (Polygon)
After selection of the geometry type from the editing toolbox, the geometry is drawn with left-mouse clicks.
Linestrings and polygons are finished with a double click on the left mouse button.
4.2.1.1 Drawing an area (Polygon):
* Select the layer and make him editable.
* Press ,,Draw Polygon Tool"
* Mark the start point with a left-mouse click in the layer view.
* Add further vertices (line-points) with left clicks.
* Close the area with a double left click.
4.2.1.2 Drawing a ,,hole" in a polygon:
* Select the layer and make him editable
* select the area with
* Press ,,Draw Polygon Tool"
* draw the new polygon/hole on top of the other.
polygon with hole
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The Editing Toolbox 4
4.2.2 Combining/Grouping Features (Geometry Collection)
Several geometries can be combined to one ,,logical" entity. Therefore the features have to be all in the same
layer.
Note: If features are combined, non-spatial attributes can be lost.
* Select the features, which should be combined with Shift +
* Right-mouse click on the layer view
* select in the mouse menu: ,,Combine selected features"
4.2.3 Resolving/Ungrouping Features
* Select the Geometry Collection with
* Right-mouse click on the layer view
* select in the mouse menu: ,,Explode selected features"
4.2.4 Selecting and Moving Features
OpenJUMP has three selection tools:
select a complete feature.
select a part of Geometry Collection
select a hole
move selected features
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4 OpenJUMP tutorial (basics)
4.3 Editing line points (vertex, vertices)
Adding a line point (vertex) to a feature
* select the feature
* add the vertex with left-mouse click on the line segment
Delete vertex
* select feature(s)
* delete the vertex by clicking on it
Move vertex
* select feature
* move the vertex by left-clicking on it and dragging the mouse
Merge vertices
* select the first node and drag, while still pressing the button, to the second node
Merge two selected vertices
* select feature (the function works only with one feature)
* select the tool and draw a box around both vertices
* press the shift-key and click on the target vertex in the box
4.4 Splitting Lines (LineStrings)
Split line
* select feature
* left click on the split position
split two intersecting lines on the intersection
* select both lines
* left click on the intersection point
12 HCU Hamburg, Dept. Geomatik
Editing Layers 5
5 Editing Layers
5.1 Layer
Layers are used to display vector data (collection of features) or raster data. The left side of the project
window shows an overview of all loaded layers in a project. Layer can be grouped by Category (e.g.
,,Working" und ,,System"). By appropriate selection of layer names one can already establish a simple
information system. In the GeoCity example below one can see a pond, roads, land parcels, and the label
,,GeoCity". All other layers are turned off (set invisible).
Overview on roads , parcels and pond of GeoCity
5.1.1 Layer Properties
Layer ...
* ... have a name
* ... can be copied, cut, removed, inserted and moved in the hierarchy
* ... can be assigned to categories
* ... can display vector- and raster-data
* ... have to be saved in a file or database
* ... have a colour visualisation (,,Rendering", page 20)
* ... can be visualised differently with respect to feature attributes
(,,Thematic Visualisation", page , ,,Labeling", page )
* ... have a attribute schema (see ,,Edit Schema" and ,,Editing Attributes", page 18 and page )
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5 OpenJUMP tutorial (basics)
In the ,,Layer" menu one can load Layer, WMS-Layer (see ,,WMS-Layer", page 16) and create layer
categories.
Menu Layer for managing layers
With a right-mouse click on the layer name specific layer properties can be changed.
After right click on layer name
14 HCU Hamburg, Dept. Geomatik
.
.
.
.
.
.
.
.
.
Editing Layers 5
Editable: To edit the features in a layer, the layer must be editable!
Zoom to layer: Zooms to the layer extend (shows all features of the layer)
Change styles... : opens the menu to change the layer visualisation (page )
View / Edit Attributes: view and modify the attributes of features (page )
View / Edit Schema: View and edit the attribute schema (page 18)
Save Dataset As File... : to saves the current layer
Move Layer Up: Moving the layer up, give them a higher priority in the visualization (like ,,bring to front")
Move Layer Down: Moving the layer down gives the layer a lower visualisation priority (like ,,send to back")
Cut selected layers: ---
Copy selected layers: ---
Remove selected layers: ---
Add new features...: Add features in well-known text format
Paste items: inserts previously copied items (only the geometries, not the attributes)
Delete all features: Deletes the features in that layer (if the layer is editable)
Select Current Layer Items: selects all items in the layer
Change SRID...: changing the SRID for this layer (only for PostGIS database connections, page 30)
5.1.2 Saving Layers and Projects
Every modified layer has to be saved on its own! Several storage format are available like ,,JUMP GML",
ESRI Shape or the ,,PostGIS" format.
With ,,Save Dataset As File...:" the current layer can be saved in a file.
The menu option ,,File>Save dataset as..." enables to save a layer also in a database (see ,,Writing Tables
", page ). If all layer are saved one can save the project using ,,File>Save Project" (not the other way
around!).
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5 OpenJUMP tutorial (basics)
5.2 WMS-Layer
The data available from WMS server (Web Map Service) can be displayed in OpenJUMP as layers. Such a
layer does only display the WMS data and does not have the same properties of usual layers. For instance
one can not draw new data in that layer or modify the data. But such layer can be serve as base for extending
the information system by vectorization / digitizing new geometries and linking them with attributes. With
,,Layer>Add a WMS query" the URL (Uniform Resource Locator) of the WMS server can be added. The
WMS server can deliver different WMS layer, which can be select using the button ,,Choose Layers" .
Note: If one wants to display the WMS layer in OpenJUMP in different layers, then one needs to redo
(,,Layer>Add a WMS query") for every WMS layer!
Adding the URL of the WMS server Choosing the WMS layer
A WMS server sometimes provides the raster data in different Coordinate Reference Systems (CRS). To
display the data the appropriate CRS has to be chosen. Here, the references systems are specified using the
EPSG notation (European Petroleum Survey Group).
After choosing the EPSG code from the list proceed
with the ,,Finish" button. It may happen that the layer
view stays empty. Using ,,View>Zoom to WMS layer"
will zoom to the selected layer. Dependent on the
network connection and the capabilities of the server it
may take a few second until the raster image has been
load.
Choosing the coordinate reference system
16 HCU Hamburg, Dept. Geomatik
Editing Layers 5
In the example below two layers are displayed with images from two WMS-Layer. With right-click on the
layer and choosing ,,Zoom to WMS layer" one zooms to the bounding box of the WMS layer. Here, a
Bounding Box defines the extent of a WMS layer.
Rivers of Europe
If several WMS layer exists on one OpenJUMP layer, one can use the function ,,Zoom to WMS layer" to
zoom to the adequate bounding box of the WMS layer. Additionally one can obtain different information on
the sent wms data by pressing the button . For Instance in the table below one can see title, name, SRS
(Spatial Reference System) and the extent of the specific bounding boxes.
Information on WMS layer of the WMS server
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6 OpenJUMP tutorial (basics)
6 Schema editing
For every layer one can create a so called schema. With the schema the non-spatial attributes of the features
are defined.
Example: One layer displays several land parcels. If one wants to capture the name of the owners, the value
or the for example the area of the land parcels, one needs to define these attributes beforehand in the layer
schema.
This schema is then applied to all features in the layer. Therefore for the modelling with GIS it is very
important to define the layers and the schema respectively in such a way, that similar objects can be stored in
the same layer. For instance it is not very useful to put land parcels and trees in the same layer since land
parcels and trees have different properties and subsequently attributes. As we will see later, the term schema
is adequate to the term Relation-Schema of a relational databases.
Every attribute, sometimes also called field, is assigned a specific datatype. OpenJUMP knows the
following datatypes: Integer (whole numbers), Double (decimal numbers), String (text), Date and
Geometry.
Note: The datatype ,,Object" is not used here. It is only for customized applications!
After right click on the layer name we can select the option to edit the schema.
Therefore the layer has to be editable!
Schema for the Layer ,,lflurstuecke" with the attributes GEOMETRY, vorname, nachname and flaeche
18 HCU Hamburg, Dept. Geomatik
Add attribute
Delete attribute
Move up
Move down
Editing Attributes 7
7 Editing Attributes
If a Schema has been set up one can add the attribute values for the features. Applying a right mouse click
on the layer name one can access to view and edit attributes.
The layer has to be editable if attribute values should be changed, but viewing is always possible .
The toolbar of the attribute window provides functions for zooming and identification of features which have
been selected in the table. For instance if one likes to know which land parcels are owned by Otto Fant one
simply marks the row of Otto. By Left click on the magnifier icon the parcel is shown and with a left click
on the flashlight the parcel outline is flashed.
To use the functions from the toolbar one or more rows in the table have to be selected.
Attribute table of the layer ,,flurstuecke"
The geometry data of the selected are displayed
if the info-button of the attribute table is
pressed. The display format can be switched
between WKT (Well-Known Text), GML
(Geography Mark-Up Language) and the CLformat
(coordinate list).
Geometry data in well-known text format (WKT)
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scrolling und zooming
Zoom selected row
Zoom to all
Show and select in layer view
Show in layer view
Show geometry data
8 OpenJUMP tutorial (basics)
8 Layer display (Styles)
The diaplay of layers, thus the display of the features in that layer can be changed using the ,,Change Styles"
window, which can be activated using the button: Therefore the layer needs not to be editable. The
window offers four possibilities to change the display: Rendering (normal styles), Colour Theming (thematic
styling), Labels (text display) und Decorations (Start-/Endpoint style of lines).
8.1 Normal Styles (Rendering)
On the tab called ,,Rendering" the following things can be changed:
* colour of lines and areas
* fill patterns of areas (Fill pattern)
* line colour style (Line pattern)
* line width
* transparency of colours
* size of vertices
Window to change the normal styles of a layer
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Layer display (Styles) 8
8.2 Colour Theming
If one likes to create a thematic map, the layer features must have attributes (see Editing Schema and
Attributes). In the example below the features of the layer ,,landwirtflaechen" have the attribute ,,nutzungsart"
with the possible values: Acker, Getreide, Grünland, Hof und Wald. The colours can be changed by using
the ,,Colour Scheme" list/box or by left-click on the attribute colour.
Thematic display of land-use with labeling
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8 OpenJUMP tutorial (basics)
Are the attribute values numerical values (no text, e.g. Integer, Double) and the values should be grouped into
intervals, then the checkbox ,,by range" must be checked. If this is done, then depended on the setting of
,,Range count" the ranges are calculated and their colours set. In the example below exists for every farming
site an attribute earning in Euro per Hectare (ertrag E/Ha). Since ,,Range count" is set to 6, one obtains six
intervals which are coloured in a green scale fashion.
Thematic Display of Ertrag pro Hektar (Earning per Hectare) with labeling
22 HCU Hamburg, Dept. Geomatik
Layer display (Styles) 8
8.3 Labeling
Attribute values of features can be displayed as text labels. In
the shown example the streets of the layer ,,strassen" are
labelled using the attribute ,,name". Therefore in the window of
the style tab ,,Labels" the box of ,,Enable labelling" has to be
checked and in the drop down list of ,,Label attribute" the attribute
name needs to be chosen. Additional possibilities for
the text display are Vertical alignment (for lines), the rotation
angle (Angle attribute) und the font size (Height attribute), which can be set with respect to the attribute values.
A fixed font size can be setup using the ,,Height" option. In contrast, if one chooses the option ,,Scale
labels with the zoom
level" the font size
will change on the
screen depended on
the zoom.
A further option: ,,Hide
overlapping labels"
is useful to switch of
labels which are
overlapped by other
labels. Finally on can
use ,,Change Colour..."
and
,,Change Font..."
to obtain the
preferred text style.
The positioning
of the labels is
done by the program
itself and
can not be influenced
by the user!
Labeling of Streets
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8 OpenJUMP tutorial (basics)
8.4 Start- and End Point Display (Decorations)
Using the options provided by the ,,decorations" window one can define the symbols for start and end points of
lines. The selected symbols need to be transferred from the left window to the right window with the arrow
buttons, to be applied on the lines. Thereby the symbols are applied to all features of a layer and not only to
single feature.
The style ,,Start-Arrow-Solid" applied to a line layer in combination with labeling
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Analysis Tools 9
9 Analysis Tools
OpenJUMP delivers a number of spatial analysis tools, which can be accessed via the ,,Tools>Analysis"
menu. Some of them are
* buffer (similar to a fringe or distance zone)
* intersections (Intersect, Overlay)
* union
* difference sets (A-B), (B-A), symmetric
9.1 Buffer
If a buffer function is applied to a geometry one obtains the fringe region around it. The function delivers
usually an area (polygon) in a new layer. This layer is automatically created. If one applies the buffer function
on a point the result will be a circular area around the point. If a line is buffered by a defined distance then
one will as well obtain a new area object with the input line as centre axis. Thereby the original input geometries
are not modified! The buffer function is applied in OpenJUMP always on all geometries, part of a layer
(note: to apply the
buffer to a single feature
use Geometry
Functions...)
This new area can be
used for further
analysis. In our example
we would
like to widen the
street ,,Hafenstraße"
to 20m. Therefore
we create a
buffer of 10m
distance around
the centre line of
the street. We obtain
a new layer
(Buffer-HafenStrasse),
with the
extended Hafenstrasse.
Extending the street Hafenstraße
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9 OpenJUMP tutorial (basics)
9.2 Overlay
The overlay function is useful to calculate the intersections between two or more areas. In our example of the
widening of the street (see Buffer) we can intersect the street buffer areas with the land parcels. The
intersection areas are returned in a new layer and can be regarded as necessary area for the extension of the
street. With help of the View/Edit Attributes button we can see the list of owners of the intersections
areas.
Intersection of ,,flurstuecke" (land parcels) and ,,Buffer-HafenStrasse"
Affected land owners
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Analysis Tools 9
9.3 Union
The union tool merges the areas of one layer to one single area. The new area is returned on a new layer.
With respect to the example of the extension of the street ,,Hafenstraßen" it is useful to do a cost
approximation. Therefore we want to use the total area of the land parcels within the layer ,,Overlay",
containing the intersection result of. To obtain the area we first apply ,,Union" to the layer "Overlay", which
results in a new layer called ,,Union." In the second step we extend the layer schema of the ,,Union"layer by
the attribute ,,area", which should be of type ,,double". Finally the third step is to use the function
,,Analysis>Calculate areas and lengths..." to calculate the total area. Note: therefore we need to have an
editable layer.
Aggregated areas of the Layer ,,Union"
Calculated total area
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9 OpenJUMP tutorial (basics)
9.4 Geometry Functions
The geometric functions, which can be found under ,,Tools>Analysis>Geometry functions..." provide
different vector algebra methods, like A-B, B-A and Symmetric Difference. These functions account for two
layers and consider only one single feature at a time.
The function Difference A-B creates a cookie cut region, whereby area B is cut out of area A and the resulting
cookie cut is presented in a new layer. For instance if B is a circle area within the circle area A, then the result
is a donut area. If you play a bit you will see that this hold similar for B-A. The function Symmetric
Difference aggregates the area of layer A with the area of layer B (Union) and subtracts from it the
overlapping area. Here as well, the resulting area is returned in a new layer.
In our new second example got Radio-GeoCity two brand new antenna poles (FunkMast-A and FunkMast-B).
But if the set them up we have to take care for interferences of radio waves, which can cause troubles in
receiving the radio. Therefore we need to find out:
1. Which area is covered by mast A without radio reception problems?
2. Which area is covered by mast B without problems?
3. Which area has good radio reception?
Radio-GeoCity's two new antenna poles
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Analysis Tools 9
The first question can we answer, if we calculate the difference A-B using the layer Buffer-FunkA and
Buffer-FunkB. The second answer can be obtained by just using the other difference function B-A.
Trouble -free reception via Mast-A (red; Difference A-B)
Finally the third question can be answered if we calculate the symmetric difference function of
Buffer-FunkA and Buffer-FunkB. Unfortunately we obtain, that the residents of the area around the street
,,Hafenstraße" will probably have difficulties to receive the radio station. If the engineers would have used
OpenJUMP for the planning, the problem could have been avoided :-)
Good radio reception (blue; Symmetric Difference)
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10 OpenJUMP tutorial (basics)
10 Connection to a PostgreSQL/PostGIS database
With an additional PlugIn it is possible to work in OpenJUMP with tables (relations) of a PostgreSQL/PostGIS
database. PostgreSQL is a object relational database management system (ORDBMS), which can be
adapted to geographic purposes using the so-called PostGIS-Extension. This extension allows to store and
edit geometries and attributes in usual relations.
To use OpenJUMP with PostGIS, one needs to install a JDBC driver (Java Data Base Connectivity) for
PostgreSQL and two OpenJUMP PlugIns. The newest JDBC-PostgreSQL driver can be obtained from the
PostgreSQL-Homepage http://www.postgresql.org/ (e.g. postgresql-8.0.309.jdc3.jar). To install the driver,
copy the file into the folder ...\lib\ext of the JavaRuntimeEnviroment
(e.g. C:\Programme\Java\jre1.5.0_04\lib\ext).
The OpenJUMP PlugIns JumpPostGISrzcn.jar and sridsupport.jar must be placed into the folder
...\lib\ext of the your OpenJUMP installation (e.g. C:\Programme\OpenJUMP\lib\ext). Thereby the
PlugIn JumpPostGISrzcn.jar handles the connection to the database server and the reading and writing of the
data. The second PlugIn sridsupport.jar is useful to assign a layer a key for the used spatial reference
system (Spatial Reference System Identifier, SRID). To establish a connection with a PostgreSQL/PostGIS
server one needs several information:
* the IP-address of the PostgreSQL server
* the port number (usually 5432)
* the database name
* the table name
* the user account name and the corresponding password
10.1 Reading Tables
If spatial tables do already exists in PostGIS format, then one can load them using ,,File>Load Dataset(s)...".
Therefore one must chose in the ,,Format:" field the option
PostGIS Table. The table is afterwards displayed as a layer in
OpenJUMP, which carries the same name like the table.
Reading PostGIS tables
30 HCU Hamburg, Dept. Geomatik
Connection to a PostgreSQL/PostGIS database 10
10.2 Writing Tables
With the menu option ,,File>Save dataset as..." a selected layer can be stored in a data base. The features
of this layer need to have an attribute which can be used a unique identifier (primary key), to have a unique
assignment for the datasets. The name of this attribute has to be entered in the ,,Unique Column:" field.
Does the table not yet exist, then a new table is created. Every table in PostGIS is assigned a SRID value
(Spatial Reference System Identifier). One condition for storing the datasets is, that they must have the same
spatial reference system. The function ,,Layer>Change SRID..." can be used to assign the currently selected
layer a SRID value, assuming the corresponding plugin has been load (see above).
NOTE: The plugin does only enable to edit existing datasets or add new datasets! But if single features are
deleted from a layer, then these datasets are not deleted on writing to the database! To delete datasets one
need to either store the layer with a new table name or delete the table beforehand in PostgreSQL (which is
unfortunately a bit cumbersome).
Writing PostGIS Tables
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11 OpenJUMP tutorial (basics)
11 Printing
In OpenJUMP it is not possible to print the displayed graphics directly. However, graphics can be saved either
as raster- (PNG, JPEG) or vector format (Scalable Vector Graphics, SVG) in a file ­ and afterwards printed
with an appropriate (opensource :) program. E.g. For raster images PhotoFiltre http://www.photofiltre.com or
GIMP and for vector graphics Inkscape http://www.inkscape.org. Thereby the vector format SVG is to prefer
since it is better scalable and easier to edit than raster graphics.
With the function ,,File>Save Image in SVG Format" one can store the current view of the project in SVG
format. Thereby it will be stored only Layer which are visible. With the opensource program Inkscape the
SVG files can be edited and printed.
GeoCity as graphics in Inkscape
32 HCU Hamburg, Dept. Geomatik
Glossary 12
12 Glossary
CRS: Coordinate Reference System
EPSG: European Petroleum Survey Group; nowadays OGP (Oil & Gas Producers) Surveying & Positioning
Committee. www.epsg.org
The Oil & Gas Producers Surveying and Positioning Committee maintains and publishes parameters and descriptions
for co-ordinate reference systems. Such parameters are give a key code, the so-called Spatial
Reference System Identifier (SRID). Such identifier numbers are for instance used by OGC compliant services
(e.g. WMS) and in PostGIS.
(See also OGC: ,,Coordinate Transformation Services").
Example: EPSG: 4326 = Geographic Co-ordinates in the WGS84 reference system
EPSG: 31466 = Gauß-Krüger Germany, 2. Meridian Zone
EPSG: 31467 = Gauß-Krüger Germany, 3. Meridian Zone
EPSG: 31468 = Gauß-Krüger Germany, 4. Meridian Zone
The files containing the information on the references (EPSG geodetic parameter dataset) are available
from the website http://www.epsg.org/ .
Feature (Object):
 Features are abstracted objects of the real world. For instance streets are abstracted and displayed
using Linestrings, buildings as areas or trees as points.
In OpenJUMP every feature has a spatial attribute (geometry) and none or several non-spatial
attributes e.g. street name, owner, tree height.
 A group of spatial elements, which represents together a piece of the real world. Often synonymously
used with the term object. A feature can also be aggregated to more complex features (objects),
consisting of more than one group of spatial elements. (Lexikon der Geoinformatik, 2001)
 A geographic feature is ,,an abstraction of a real world phenomenon ... associated with a location
relative to Earth". A feature has spatial attributes (polygons, points, etc.) and non-spatial attributes
(strings, dates, numbers). (JUMP Workbench User's Guide, 2004)
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12 OpenJUMP tutorial (basics)
GeometryCollection: Collection of several features of one layer to one feature.
GML: Geography Mark-Up Language; see also on http://www.opengeospatial.org/
GNU General Public License: License type of free software; http://www.fsf.org/licensing/licenses/gpl.html
Inkscape: Editor for vector graphics (Open Source); http://www.inkscape.org/
Item: Graphic display of a features in OpenJUMP.
JPEG: Joint Photographic Experts Group; graphic format; http://www.jpeg.org/
JUMP: Unified Mapping Platform; A Geographical Information System; http://www.jump-project.org/
Mapserver: A development environment for the setup of internet applications with dynamic map content;
http://mapserver.gis.umn.edu/
OGC: Open Geospatial Consortium; http://www.opengeospatial.org/
International society for the standardization of formats and interfaces for GIS and Location Based Services
(LBS) applications. It is nowadays made up largely by companies and only to a smaller part by research
institutes.
OGP: Oil & Gas Producer; http://www.ogp.org.uk/
OGP Surveying and Positioning Committee: former EPSG, http://www.epsg.org/
OpenGIS: see OGC; http://www.opengeospatial.org/
OpenJUMP: Geographical Information System; extended version of JUMP;
http://openjump.org/wiki/show/HomePage
Open Source: the source code of a software is open to everybody; http://en.wikipedia.org/wiki/Open_source
PNG: Portable Network Graphics; graphic format for loss less storing of images
PostGIS: Extension of PostgreSQL for the work with geographic objects; http://postgis.refractions.net/
PostgreSQL: Object relational database management system; http://www.postgresql.org/
34 HCU Hamburg, Dept. Geomatik
Glossary 12
Refractions Research: Canadian Company which developed PostGIS and took part on the development of
JUMP; http://www.refractions.net/
Spatial attributes: e.g. point, line, area.
Spatial information: geo-information, related to a place on the earth (or other stellar object)
SRID: Spatial Reference System Identifier; key code for specific (earth) co-ordinate systems
SRS: Spatial Reference System
SVG: Scaleable Vector Graphics; recommended by the W3C to store vector graphics;
http://www.w3.org/Graphics/SVG/
URL: Uniform Resource Locator; e.g. a link in a browser.
Vertex, vertices: node, corner point.
Vivid Solutions: Canadian Company which developed JUMP in large parts; http://www.vividsolutions.com/
W3C: World Wide Web Consortium; http://www.w3.org/
Well-Known Binary (WKB): Binary representation for geometries, defined in the OpenGIS (OGC) document
,,OpenGIS Simple Features Specification For SQL" .
Wiki: A Wiki, sometimes called WikiWiki or WikiWeb, is a collection of WebPages in the World Wide Web,
which can not only be read by the users, but also online edited. Thus, Wikis are alike Content Management
Systems. The name emerged from the Hawaiian word wikiwiki, which means "fast". (Wikipedia, 2005)
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12 OpenJUMP tutorial (basics)
Well-Known Text (WKT): Textual representation of geometries, defined in the OpenGIS (OGC) document
,,OpenGIS Simple Features Specification For SQL". Because of the textual representation they are easier to
read for humans. For instance a point is represented by 'POINT (10 15)'.
Geometry types in WKT-Format (Source: OpenGIS Simple Features Specification for SQL)
WKB: see Well-Known Binary
WKT: see Well-Known Text
WMS: Web Map Service; An internet service which delivers on standardised requests standardised data for
map like (raster) display of geodata. This services is specified as an OGC standard.
36 HCU Hamburg, Dept. Geomatik
Literature References 13
13 Literature References
Aquino, J., and M. Davis (2004):
JUMP Workbench User's Guide, Vivid Solutions
Aquino, J., and D. Kim (2003):
JUMP Developer's Guide, Vivid Solutions
Bill, R., and M. L. Zehner (2001):
Lexikon der Geoinformatik, Wichmann Verlag
Burrough, P., and R. A. McDonnel (1998): (comprehensive and technical textbook)
Principles of Geographical Information Systems. 2nd Edition, Oxford University Press
Jones, C. B. (1997): (comprehensive and technical textbook)
Geographical Information Systems and Computer Cartography. Addison-Wesley Longman.
Lake, R., D. S. Burggraf, M.Trninic and L. Rae (2004):
Geography Mark-Up Language (GML), John Wiley & Sons, Ltd
Goodchild, M. F., D. J. Maguire and D. W. Rhind (2005): (reference book)
Geographical Information Systems: Principles, Techniques, Management and Applications. 2nd Ed.,
Wiley John + Sons .
OGC (2003):
OpenGIS Geography Markup Language (GML) Implementation Specification, Open GIS Consortium
OGC (2001):
OpenGIS Implementation Specification: Coordinate Transformation Services, Open GIS Consortium
OGC (1999):
OpenGIS Simple Features Specification For SQL Revision 1.1, Open GIS Consortium
OGC (2004):
Web Map Service (WMS), Version: 1.3, Open GIS Consortium
Refractions Research (2005):
PostGIS Manual
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13 OpenJUMP tutorial (basics)
The PostgreSQL Global Development Group (2005):
PostgreSQL 8.1.0 Documentation
38 HCU Hamburg, Dept. Geomatik
Link Collection 14
14 Link Collection
Inkscape http://www.inkscape.org/
JUMP http://www.jump-project.org/
Jump Pilot Project http://jump-pilot.sourceforge.net/
MapServer http://mapserver.gis.umn.edu/
OGP Surveying & Positioning Committee http://www.epsg.org/
Open Geospatial Consortium http://www.opengeospatial.org/
OpenJUMP http://openjump.org
PIROL, Fachhochschule Osnabrück http://www.al.fh-osnabrueck.de/jump-download.html
PostGIS http://postgis.refractions.net/
PostgreSQL http://www.postgresql.org/
HCU Hamburg, Dept. Geomatik 39
15 OpenJUMP tutorial (basics)
15 Index
Analysis...............................................................25
Area.................................................................8, 10
Attributes.............................................................19
Attribute Values...................................................21
Bounding Box......................................................17
Buffer...................................................................25
Colour Theming...................................................21
Colour Scheme...................................................21
Data.......................................................................7
Data Types..........................................................18
Decorations.........................................................24
Difference A-B.....................................................28
Double.................................................................18
Editing Toolbox.....................................................9
Enable Labelling..................................................23
End Symbol.........................................................24
Features................................................................5
Fill pattern............................................................20
GeoCity...............................................................13
Geometric Functions...........................................28
Geometry Collection............................................11
Grid Lines..............................................................9
Glossary..............................................................33
GML....................................................................19
GNU General Public License................................4
Graphical Editor....................................................8
Hole.....................................................................11
Inkscape..............................................................32
Integer.................................................................18
IP-Address..........................................................30
JDBC-Driver .......................................................30
JUMP.....................................................................4
JUMP GML..........................................................15
JumpPostGISrzcn.jar .........................................30
Label attribute.....................................................23
Labels..................................................................23
Layer...............................................................5, 13
Layer View.............................................................5
Layer Display.......................................................20
Layer Properties..................................................13
Layer Name...........................................................8
Lines..........................................................8, 10, 12
Line Width...........................................................20
Linestring.............................................................10
Line Styles...........................................................20
Link Collection.....................................................39
Literature References.........................................37
Loading Data.........................................................7
Node....................................................................12
Open Source.........................................................4
OpenJUMP............................................................4
Options (Snap/Grid)..............................................9
Overlay................................................................26
PlugIn..................................................................30
Point................................................................8, 10
Polygon...............................................................10
Port Number........................................................30
PostGIS.........................................................15, 30
PostGIS-Extension..............................................30
PostgreSQL.........................................................30
PostgreSQL/PostGIS Database .........................30
Printing................................................................32
Project...................................................................5
Project View..........................................................5
Refractions Research...........................................4
Rendering............................................................20
Scalable Vector Graphics....................................32
Schema...............................................................18
Saving Layer and Projects..................................15
Snapping...............................................................9
SRID....................................................................30
sridsupport.jar.....................................................30
Start- Endpoint Style...........................................24
String...................................................................18
40 HCU Hamburg, Dept. Geomatik
Index 15
Styles..................................................................20
SVG....................................................................32
Symmetric Difference.........................................28
Thematic Styling.................................................21
Transparency.....................................................20
Union..................................................................27
Vertex.................................................................12
Vertical alignment...............................................23
Vertices...............................................................12
Vivid Solutions................................................4, 35
Web Map Service...............................................16
WKT...................................................................19
WMS.............................................................16, 36
WMS-Layer........................................................16
WMS-Server.......................................................16
HCU Hamburg, Dept. Geomatik 41