org.deegree.graphics.sld
Interface Rule

All Known Implementing Classes:

Rule_Impl

public interface Rule

A rule is used to attach a condition to and group the individual symbolizers used for rendering. The Title and Abstract describe the rule and may be used to generate a legend, as may the LegendGraphic. The Filter, ElseFilter, MinScale, and MaxScale elements allow the selection of features and rendering scales for a rule. The scale selection works as follows. When a map is to be rendered, the scale denominator is computed and all rules in all UserStyles that have a scale outside of the request range are dropped. (This also includes Rules that have an ElseFilter.) An ElseFilter is simply an ELSE condition to the conditions (Filters) of all other rules in the same UserStyle. The exact meaning of the ElseFilter is determined after Rules have been eliminated for not fitting the rendering scale. This definition of the behaviour of ElseFilters may seem a little strange, but it allows for scale- dependent and scale-independent ELSE conditions. For the Filter, only SqlExpression is available for specification, but this is a hack and should be replaced with Filter as defined in WFS. A missing Filter element means "always true". If a set of Rules has no ElseFilters, then some features may not be rendered (which is presumably the desired behavior). The Scales are actually scale denominators (as double floats), so "10e6" would be interpreted as 1:10M. A missing MinScale means there is no lower bound to the scale- denominator range (lim[x->0+](x)), and a missing MaxScale means there is no upper bound (infinity). 0.28mm

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Version:

$Revision: 1.3 $ $Date: 2004/01/12 14:48:13 $

Author:

Andreas Poth

Method Summary

void	addSymbolizer(Symbolizer symbolizer) Adds a to a set of Symbolizers.
java.lang.String	getAbstract() returns the human readable abstract of the rule
Filter	getFilter() The Filter element has a relatively straightforward meaning.
LegendGraphic	getLegendGraphic() The LegendGraphic element gives an optional explicit Graphic symbol to be displayed in a legend for this rule.
double	getMaxScaleDenominator() The MinScaleDenominator and MaxScaleDenominator elements of a Rule define the range of map-rendering scales for which the rule should be applied.
double	getMinScaleDenominator() The MinScaleDenominator and MaxScaleDenominator elements of a Rule define the range of map-rendering scales for which the rule should be applied.
java.lang.String	getName() returns the name of the rule. this for machine interpreting.
Symbolizer[]	getSymbolizers() Embedded inside of Rules, which group conditions for styling features, are Symbolizers.
java.lang.String	getTitle() returns the human readable title of the rule
boolean	hasElseFilter() The ElseFilter allows rules to be specified that are activated for features are not selected by any other rule in a feature-type style.
void	removeSymbolizer(Symbolizer symbolizer) Removes a from a set of Symbolizers.
void	setAbstract(java.lang.String abstract_) Sets the abstract attribute's value of the Rule.
void	setElseFilter(boolean elseFilter) sets the
void	setFilter(Filter filter) Sets the Filter.
void	setLegendGraphic(LegendGraphic legendGraphic) Sets the LegendGraphic element
void	setMaxScaleDenominator(double maxScaleDenominator) Sets the MaxScaleDenominator.
void	setMinScaleDenominator(double minScaleDenominator) Sets the MinScaleDenominator.
void	setName(java.lang.String name) Sets the name attribute's value of the rule.
void	setSymbolizers(Symbolizer[] symbolizers) Sets a set of s.
void	setTitle(java.lang.String title) Sets the title attribute's value of the rule.

Method Detail

getName

public java.lang.String getName()

returns the name of the rule. this for machine interpreting.

Returns:

the name of the rule

setName

public void setName(java.lang.String name)

Sets the name attribute's value of the rule.

Parameters:

name - the name of the rule

getTitle

public java.lang.String getTitle()

returns the human readable title of the rule

Returns:

the title of the rule

setTitle

public void setTitle(java.lang.String title)

Sets the title attribute's value of the rule.

Parameters:

title - the title of the rule

getAbstract

public java.lang.String getAbstract()

returns the human readable abstract of the rule

Returns:

the abstract of the rule

setAbstract

public void setAbstract(java.lang.String abstract_)

Sets the abstract attribute's value of the Rule.

Parameters:

abstract_ - the abstract of the rule

getLegendGraphic

public LegendGraphic getLegendGraphic()

The LegendGraphic element gives an optional explicit Graphic symbol to be displayed in a legend for this rule.

Returns:

the legendGraphic of the rule

setLegendGraphic

public void setLegendGraphic(LegendGraphic legendGraphic)

Sets the LegendGraphic element

Parameters:

legendGraphic - the legendGraphic of the rule

getFilter

public Filter getFilter()

The Filter element has a relatively straightforward meaning. The syntax of the Filter element is defined in the WFS specification and allows both attribute (property) and spatial filtering.

Returns:

the filter element

setFilter

public void setFilter(Filter filter)

Sets the Filter.

Parameters:

filter - the filter element

hasElseFilter

public boolean hasElseFilter()

The ElseFilter allows rules to be specified that are activated for features are not selected by any other rule in a feature-type style.

Returns:

true if the rule has an elseFilter

setElseFilter

public void setElseFilter(boolean elseFilter)

sets the

Parameters:

elseFilter - an elseFilter

getMinScaleDenominator

public double getMinScaleDenominator()

The MinScaleDenominator and MaxScaleDenominator elements of a Rule define the range of map-rendering scales for which the rule should be applied. The MinScaleDenominator and MaxScaleDenominator elements, as their names suggest, are simply the minimum and maximum ranges of scale (denominators) of maps for which a rule should apply.

Returns:

the MinScaleDenominator for the rule

setMinScaleDenominator

public void setMinScaleDenominator(double minScaleDenominator)

Sets the MinScaleDenominator.

Parameters:

minScaleDenominator - the MinScaleDenominator for the rule

getMaxScaleDenominator

public double getMaxScaleDenominator()

The MinScaleDenominator and MaxScaleDenominator elements of a Rule define the range of map-rendering scales for which the rule should be applied. The MinScaleDenominator and MaxScaleDenominator elements, as their names suggest, are simply the minimum and maximum ranges of scale (denominators) of maps for which a rule should apply.

Returns:

the MaxScaleDenominator for the rule

setMaxScaleDenominator

public void setMaxScaleDenominator(double maxScaleDenominator)

Sets the MaxScaleDenominator.

Parameters:

maxScaleDenominator - the MaxScaleDenominator for the rule

getSymbolizers

public Symbolizer[] getSymbolizers()

Embedded inside of Rules, which group conditions for styling features, are Symbolizers. A symbolizer describes how a feature is to appear on a map. The symbolizer describes not just the shape that should appear but also such graphical properties as color and opacity. A symbol is obtained by specifying one of a small number of different types of symbolizer and then supplying parameters to override its default behaviour. Currently, five types of symbolizers are defined.

The Symbolizers will be returned in the sequece of their occurence with in the rule definition. Its the users function to determine what type of Symbolizer(s) are returned. This can be done for example by using the instanceof operator of Java.

Returns:

the Symbolizer for the rule

setSymbolizers

public void setSymbolizers(Symbolizer[] symbolizers)

Sets a set of s.

Parameters:

symbolizers - symbolizers for the rule

addSymbolizer

public void addSymbolizer(Symbolizer symbolizer)

Adds a to a set of Symbolizers.

Parameters:

symbolizer - symbolizer to add

removeSymbolizer

public void removeSymbolizer(Symbolizer symbolizer)

Removes a from a set of Symbolizers.

Parameters:

symbolizer - symbolizer to remove