org.deegree.graphics.legend
Class LegendElement

java.lang.Object
  org.deegree.graphics.legend.LegendElement

Direct Known Subclasses:

LegendElementCollection

public class LegendElement
extends java.lang.Object

The implements the basic legend element. a legend element may has a label that can be set to eight positions relative to the legend graphic. A LegendElement can be activated or deactivated. It depends on the using application what effect this behavior will have.

LegendElements can be collected in a LegendElementCollection which also is a LegendElement to group elements or to create more complex elements.

Each LegendElement is able to paint itself as BufferedImage

Version:

$Revision: 7363 $ $Date: 2007-05-29 20:47:55 +0200 (Di, 29 Mai 2007) $

Author:

Andreas Poth

Field Summary

protected boolean	active A flag signaling if the legend is active initialized with false.
protected java.awt.image.BufferedImage	bi The icon of the legend
protected int	bufferBetweenLegendAndLabel The width in pixels between the legend and it's label initialized with 10;
protected int	height The height of the legend element initialized with 0;
protected java.lang.String	label The initial empty label.
protected int	labelPosition The label position initialized with -1.
protected double	orientation The orientation initialized with 0.
protected java.util.ArrayList<Rule>	ruleslist the list of rules
protected int	width The width of the legend element initialized with 0;

Constructor Summary

protected	LegendElement() empty constructor
(package private)	LegendElement(java.awt.image.BufferedImage legendImage)
(package private)	LegendElement(Rule[] rules, java.lang.String label, double orientation, int labelPosition, boolean active, int width, int height) constructor

Method Summary

void	addRule(Rule rule) adds a rule to the ArrayList ruleslist
protected int[]	calculateFontMetrics(java.lang.String label) calculates the FontMetrics of the LegendLabel in pixels.
protected void	drawLineStringLegend(java.awt.Graphics2D g, LineSymbolizer ls, int width, int height) draws a legendsymbol, if the SLD defines a line
protected void	drawPointLegend(java.awt.Graphics g, PointSymbolizer c, int width, int height) draws a legendsymbol, if the SLD defines a point
protected void	drawPolygonLegend(java.awt.Graphics2D g, PolygonSymbolizer ps, int width, int height) draws a legendsymbol, if the SLD defines a polygon
java.awt.image.BufferedImage	exportAsImage(java.lang.String mime) exports the LegendElement as BufferedImage
int	getBufferBetweenLegendAndLabel() returns the buffer place between the legend symbol and the legend label in pixels
int	getHeight()
java.lang.String	getLabel() returns the label set to LegendElement.
double	getLabelOrientation() returns the current orientation of the label of the LegendElement in radians.
int	getLabelPlacement() returns the placement of the label relative to the legend symbol.
Rule[]	getRules() gets the Rules as an array
int	getWidth()
boolean	isActive()
void	setActive(boolean active) activates or deactivates the label
void	setBufferBetweenLegendAndLabel(int i)
void	setHeight(int height) sets the height of the LegendSymbol (in pixels)
void	setLabel(java.lang.String label) sets the label of the LegendElement
void	setLabelOrientation(double orientation) sets the orientation of the label of the LegendElement.
void	setLabelPlacement(int labelPosition) sets the placement of the label relative to the legend symbol.
void	setRules(Rule[] rules) sets the rules
void	setWidth(int width) sets the width of the LegendSymbol (in pixels)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ruleslist

protected java.util.ArrayList<Rule> ruleslist

the list of rules

label

protected java.lang.String label

The initial empty label.

orientation

protected double orientation

The orientation initialized with 0.

labelPosition

protected int labelPosition

The label position initialized with -1.

active

protected boolean active

A flag signaling if the legend is active initialized with false.

width

protected int width

The width of the legend element initialized with 0;

height

protected int height

The height of the legend element initialized with 0;

bufferBetweenLegendAndLabel

protected int bufferBetweenLegendAndLabel

The width in pixels between the legend and it's label initialized with 10;

bi

protected java.awt.image.BufferedImage bi

The icon of the legend

Constructor Detail

LegendElement

protected LegendElement()

empty constructor

LegendElement

LegendElement(java.awt.image.BufferedImage legendImage)

Parameters:

legendImage - the icon of the legend.

LegendElement

LegendElement(Rule[] rules,
              java.lang.String label,
              double orientation,
              int labelPosition,
              boolean active,
              int width,
              int height)

constructor

Parameters:

rules - the different rules from the SLD

label - the label beneath the legend symbol

orientation - the rotation of the text in the legend

labelPosition - the position of the text according to the symbol

active - whether the legendsymbol is active or not

width - the requested width of the legend symbol

height - the requested height of the legend symbol

Method Detail

getRules

public Rule[] getRules()

gets the Rules as an array

Returns:

array of sld rules

addRule

public void addRule(Rule rule)

adds a rule to the ArrayList ruleslist

Parameters:

rule - a sld rule

setRules

public void setRules(Rule[] rules)

sets the rules

Parameters:

rules - an array of sld rules

setLabel

public void setLabel(java.lang.String label)

sets the label of the LegendElement

Parameters:

label - label of the LegendElement

getLabel

public java.lang.String getLabel()

returns the label set to LegendElement. If no label is set, the method returns null

Returns:

label of the LegendElement or null

setLabelOrientation

public void setLabelOrientation(double orientation)

sets the orientation of the label of the LegendElement. A label can have an orientation from -90� to 90� expressed in radians, where 0� is horizontal

Parameters:

orientation -

getLabelOrientation

public double getLabelOrientation()

returns the current orientation of the label of the LegendElement in radians. If the element hasn't a label Double.NEGATIVE_INFINITY will be returned.

Returns:

orientation of the label of the LegendElement in radians

setLabelPlacement

public void setLabelPlacement(int labelPosition)

sets the placement of the label relative to the legend symbol. Possible values are:

• LP_TOPCENTER
• LP_TOPLEFT
• LP_TOPRIGHT
• LP_RIGHT
• LP_LEFT
• LP_BOTTOMCENTER
• LP_BOTTOMRIGHT
• LP_BOTTOMLEFT

   +---+---+---+
   | 1 | 0 | 2 |
   +---+---+---+
   | 4 |LEG| 3 |
   +---+---+---+
   | 7 | 5 | 6 |
   +---+---+---+
 

An implementation of the interface may not supoort all positions.

Parameters:

labelPosition -

getLabelPlacement

public int getLabelPlacement()

returns the placement of the label relative to the legend symbol. If the element hasn't a label LegendElement.LP_NOLABEL will be returned. Otherwise possible values are:

• LP_TOPCENTER
• LP_TOPLEFT
• LP_TOPRIGHT
• LP_RIGHT
• LP_LEFT
• LP_BOTTOMCENTER
• LP_BOTTOMRIGHT
• LP_BOTTOMLEFT

Returns:

coded placement of the label relative to the legend symbol

setActive

public void setActive(boolean active)

activates or deactivates the label

Parameters:

active -

isActive

public boolean isActive()

Returns:

the activtion-status of the label

setWidth

public void setWidth(int width)

sets the width of the LegendSymbol (in pixels)

Parameters:

width -

getWidth

public int getWidth()

Returns:

the width of the LegendSymbol (in pixels)

setHeight

public void setHeight(int height)

sets the height of the LegendSymbol (in pixels)

Parameters:

height -

getHeight

public int getHeight()

Returns:

the height of the LegendSymbol (in pixels)

getBufferBetweenLegendAndLabel

public int getBufferBetweenLegendAndLabel()

returns the buffer place between the legend symbol and the legend label in pixels

Returns:

the buffer as integer in pixels

setBufferBetweenLegendAndLabel

public void setBufferBetweenLegendAndLabel(int i)

Parameters:

i - the buffer as integer in pixels

See Also:

getBufferBetweenLegendAndLabel()

drawPointLegend

protected void drawPointLegend(java.awt.Graphics g,
                               PointSymbolizer c,
                               int width,
                               int height)
                        throws LegendException

draws a legendsymbol, if the SLD defines a point

Parameters:

g - the graphics context

c - the PointSymbolizer representing the drawable point

width - the requested width of the symbol

height - the requested height of the symbol

Throws:

LegendException - is thrown, if the parsing of the sld failes.

drawLineStringLegend

protected void drawLineStringLegend(java.awt.Graphics2D g,
                                    LineSymbolizer ls,
                                    int width,
                                    int height)
                             throws LegendException

draws a legendsymbol, if the SLD defines a line

Parameters:

g - the graphics context

ls - the LineSymbolizer representing the drawable line

width - the requested width of the symbol

height - the requested height of the symbol

Throws:

LegendException - is thrown, if the parsing of the sld failes.

drawPolygonLegend

protected void drawPolygonLegend(java.awt.Graphics2D g,
                                 PolygonSymbolizer ps,
                                 int width,
                                 int height)
                          throws LegendException

draws a legendsymbol, if the SLD defines a polygon

Parameters:

g - the graphics context

ps - the PolygonSymbolizer representing the drawable polygon

width - the requested width of the symbol

height - the requested height of the symbol

Throws:

LegendException - if the parsing of the sld failes.

calculateFontMetrics

protected int[] calculateFontMetrics(java.lang.String label)

calculates the FontMetrics of the LegendLabel in pixels. It returns an 3-dimensional array containing [0] the width, [1] the ascent and [2] the descent.

Parameters:

label - the label of the LegendElement

Returns:

the 3-dimensional INT-Array contains [0] the width of the string, [1] the ascent and [2] the descent.

exportAsImage

public java.awt.image.BufferedImage exportAsImage(java.lang.String mime)
                                           throws LegendException

exports the LegendElement as BufferedImage

Parameters:

mime -

Returns:

the image

Throws:

LegendException