javax.swing.border
Class LineBorder

java.lang.Object
  extended by javax.swing.border.AbstractBorder
      extended by javax.swing.border.LineBorder
All Implemented Interfaces:
Serializable, Border
Direct Known Subclasses:
BorderUIResource.LineBorderUIResource

public class LineBorder
extends AbstractBorder

A border that consists of a line whose thickness and color can be specified. There also is a variant with rounded corners.

See Also:
Serialized Form

Field Summary
protected  Color lineColor
          The color of the line.
protected  boolean roundedCorners
          Indicates whether the line is drawn with rounded corners (true) or not ((false).
protected  int thickness
          The width of the line in pixels.
 
Constructor Summary
LineBorder(Color color)
          Constructs a LineBorder given its color.
LineBorder(Color color, int thickness)
          Constructs a LineBorder given its color and thickness.
LineBorder(Color color, int thickness, boolean roundedCorners)
          Constructs a LineBorder given its color, thickness, and whether it has rounded corners.
 
Method Summary
static Border createBlackLineBorder()
          Returns a black, one pixel thick, plain LineBorder.
static Border createGrayLineBorder()
          Returns a gray, one pixel thick, plain LineBorder.
 Insets getBorderInsets(Component c)
          Measures the width of this border.
 Insets getBorderInsets(Component c, Insets insets)
          Measures the width of this border, storing the results into a pre-existing Insets object.
 Color getLineColor()
          Returns the color of the line.
 boolean getRoundedCorners()
          Returns whether this LineBorder os drawm with rounded or with plain corners.
 int getThickness()
          Returns the thickness of the line in pixels.
 boolean isBorderOpaque()
          Determines whether this border fills every pixel in its area when painting.
 void paintBorder(Component c, Graphics g, int x, int y, int width, int height)
          Paints the line border around a given Component.
 
Methods inherited from class javax.swing.border.AbstractBorder
getInteriorRectangle, getInteriorRectangle
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

thickness

protected int thickness
The width of the line in pixels.


lineColor

protected Color lineColor
The color of the line.


roundedCorners

protected boolean roundedCorners
Indicates whether the line is drawn with rounded corners (true) or not ((false).

Constructor Detail

LineBorder

public LineBorder(Color color)
Constructs a LineBorder given its color. The border will be one pixel thick and have plain corners.

Parameters:
color - the color for drawing the border.
See Also:
LineBorder(java.awt.Color, int, boolean)

LineBorder

public LineBorder(Color color,
                  int thickness)
Constructs a LineBorder given its color and thickness. The border will have plain corners.

Parameters:
color - the color for drawing the border.
thickness - the width of the line in pixels.
See Also:
LineBorder(java.awt.Color, int, boolean)

LineBorder

public LineBorder(Color color,
                  int thickness,
                  boolean roundedCorners)
Constructs a LineBorder given its color, thickness, and whether it has rounded corners.

[An illustration of two LineBorders]

Note that the enlarged view in the right-hand picture shows that the implementation draws one more pixel than specified, provided that roundedCorders is true and anti-aliasing is turned on while painting. While this might be considered a bug, the Sun reference implementation (at least JDK 1.3.1 on Apple MacOS X 10.1.5) can be observed to fill exactly the same pixels as shown above. The GNU Classpath LineBorder replicates the observed behavior of the Sun implementation.

Parameters:
color - the color for drawing the border.
thickness - the width of the line in pixels.
roundedCorners - true for rounded corners, false for plain corners.
Since:
1.3
Method Detail

createBlackLineBorder

public static Border createBlackLineBorder()
Returns a black, one pixel thick, plain LineBorder. The method may always return the same (singleton) LineBorder instance.

Returns:
The border.

createGrayLineBorder

public static Border createGrayLineBorder()
Returns a gray, one pixel thick, plain LineBorder. The method may always return the same (singleton) LineBorder instance.

Returns:
The border.

paintBorder

public void paintBorder(Component c,
                        Graphics g,
                        int x,
                        int y,
                        int width,
                        int height)
Paints the line border around a given Component.

Specified by:
paintBorder in interface Border
Overrides:
paintBorder in class AbstractBorder
Parameters:
c - the component whose border is to be painted.
g - the graphics for painting.
x - the horizontal position for painting the border.
y - the vertical position for painting the border.
width - the width of the available area for painting the border.
height - the height of the available area for painting the border.

getBorderInsets

public Insets getBorderInsets(Component c)
Measures the width of this border.

Specified by:
getBorderInsets in interface Border
Overrides:
getBorderInsets in class AbstractBorder
Parameters:
c - the component whose border is to be measured.
Returns:
an Insets object whose left, right, top and bottom fields indicate the width of the border at the respective edge, which is the thickness of the line.
See Also:
getBorderInsets(java.awt.Component, java.awt.Insets)

getBorderInsets

public Insets getBorderInsets(Component c,
                              Insets insets)
Measures the width of this border, storing the results into a pre-existing Insets object.

Overrides:
getBorderInsets in class AbstractBorder
Parameters:
insets - an Insets object for holding the result values. After invoking this method, the left, right, top and bottom fields indicate the width of the border at the respective edge, which is the thickness of the line.
c - the component that the border applies to (ignored here, subclasses may use it).
Returns:
the same object that was passed for insets.
See Also:
getBorderInsets(Component)

getLineColor

public Color getLineColor()
Returns the color of the line.

Returns:
The line color (never null).

getThickness

public int getThickness()
Returns the thickness of the line in pixels.

Returns:
The line thickness (in pixels).

getRoundedCorners

public boolean getRoundedCorners()
Returns whether this LineBorder os drawm with rounded or with plain corners.

Returns:
true if the corners are rounded, false if the corners are plain.

isBorderOpaque

public boolean isBorderOpaque()
Determines whether this border fills every pixel in its area when painting.

Specified by:
isBorderOpaque in interface Border
Overrides:
isBorderOpaque in class AbstractBorder
Returns:
true if the corners are plain and the line color is fully opaque; false if the corners are rounded or the line color is partially transparent.