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            <div id=PageTitle>How to Use Borders</div>
            <blockquote>

Every <code>JComponent</code>
can have one or more borders.
Borders are incredibly useful objects
that, while not themselves components,
know how to draw
the edges of Swing components.
Borders are useful not only for drawing lines and fancy edges,
but also for providing titles and empty space around components.

<blockquote><hr><strong>Note:</strong>&nbsp;
Our examples set borders on <code>JPanel</code>s,
<code>JLabel</code>s, and custom subclasses of
<code>JComponent</code>.  Although technically you can set the border
on any object that inherits from <code>JComponent</code>, the look and feel
implementation of many standard Swing components doesn't work well with
user-set borders.  In general, when you want to set a border on a
standard Swing component other than <code>JPanel</code> or <code>JLabel</code>,
we recommend that you put the component in a <code>JPanel</code> and set
the border on the <code>JPanel</code>.

<p>
The GTK+ look and feel handles borders differently
than other look and feels.  Please refer to the
<a class="OutsideLink" target="_blank" href="http://java.sun.com/j2se/1.4.2/docs/guide/swing/1.4/Post1.4.html#gtk">1.4.2 release notes</a> for details.
<hr></blockquote>

<p>

To put a border around a <code>JComponent</code>,
you use its
<code>setBorder</code> method.
You can use the 
<a class="APILink" target="_blank" href="http://java.sun.com/javase/6/docs/api/javax/swing/BorderFactory.html"><code>BorderFactory</code></a> class to create most of the borders that Swing provides.
If you need a reference to a border &#151; say, because you
want to use it in multiple components &#151; you can save
it in a variable of type
<a class="APILink" target="_blank" href="http://java.sun.com/javase/6/docs/api/javax/swing/border/Border.html"><code>Border</code></a>. Here is an example of code that creates a bordered container:

<p>
<blockquote><pre>
JPanel pane = new JPanel();
pane.setBorder(BorderFactory.createLineBorder(Color.black));
</pre></blockquote>
<p>

Here's a picture of the container,
which contains a label component.
The black line drawn by the border
marks the edge of the container.

<p><center><IMG SRC="../../figures/uiswing/components/BorderDemo-line.png" WIDTH="300" HEIGHT="38" ALIGN="BOTTOM" ALT="A line border"></center></p>
The rest of this page discusses the following topics:

<ul>
<li> <a href="#demo">The BorderDemo Example</a>
<li> <a href="#code">Using the Borders Provided by Swing</a>
<li> <a href="#custom">Creating Custom Borders</a>
<li> <a href="#api">The Border API</a>
<li> <a href="#eg">Examples of Using Borders</a>
</ul>

</blockquote>
<h3>
<a name="demo">The BorderDemo Example</a>
</h3>
<blockquote>

The following pictures show an application
called <code>BorderDemo</code> that
displays the borders Swing provides.
We show the code for creating these borders
a little later,
in <a href="#code">Using the Borders Provided by Swing</a>.



<p>
You can 
<a href="http://java.sun.com/docs/books/tutorialJWS/uiswing/components/examples/BorderDemo.jnlp">run BorderDemo</a> using
<a href=http://java.sun.com/products/javawebstart>
Java<sup><font size=-2>TM</font></sup> Web Start</a>.

Or, to compile and run the example yourself, consult the
<a href="examples/index.html#BorderDemo">example index</a>.

<p><center><IMG SRC="../../figures/uiswing/components/BorderDemo1.png" WIDTH="328" HEIGHT="336" ALIGN="BOTTOM" ALT="BorderDemo: Simple Borders"></center></p>
The next picture shows some matte borders.
When creating a matte border,
you specify how many pixels it occupies
at the top, left, bottom, and right of a component.
You then specify either a color or an icon
for the matte border to draw.
You need to be careful when choosing the icon
and determining your component's size;
otherwise, the icon might
get chopped off or have mismatch at the component's corners.

<p><center><IMG SRC="../../figures/uiswing/components/BorderDemo2.png" WIDTH="328" HEIGHT="336" ALIGN="BOTTOM" ALT="BorderDemo: Matte Borders"></center></p>
The next picture shows titled borders.
Using a titled border,
you can convert any border into
one that displays a text description.
If you don't specify a border,
a look-and-feel-specific border is used.
For example, the default titled border 
in the Java look and feel uses a gray line,
and the default titled border in the Windows look and feel
uses an etched border.
By default, the title straddles the upper left
of the border,
as shown at the top of the following figure.

<p><center><IMG SRC="../../figures/uiswing/components/BorderDemo3.png" WIDTH="328" HEIGHT="336" ALIGN="BOTTOM" ALT="BorderDemo: Titled Borders"></center></p>
The next picture shows compound borders.
With compound borders, you can combine any two borders,
which can themselves be compound borders.

<p><center><IMG SRC="../../figures/uiswing/components/BorderDemo4.png" WIDTH="328" HEIGHT="336" ALIGN="BOTTOM" ALT="BorderDemo: Compound Borders"></center></p>
</blockquote>
<h3>
<a name="code">Using the Borders Provided by Swing</a>
</h3>
<blockquote>

The code that follows shows how to create and set the borders you
saw in the preceding figures. You can find the program's code in

<a class="SourceLink" target="_blank" href="examples/BorderDemo.java"><code>BorderDemo.java</code></a>.

<p>
<blockquote><pre>
//Keep references to the next few borders,
//for use in titles and compound borders.
Border blackline, raisedetched, loweredetched,
       raisedbevel, loweredbevel, empty;

blackline = BorderFactory.createLineBorder(Color.black);
raisedetched = BorderFactory.createEtchedBorder(EtchedBorder.RAISED);
loweredetched = BorderFactory.createEtchedBorder(EtchedBorder.LOWERED);
raisedbevel = BorderFactory.createRaisedBevelBorder();
loweredbevel = BorderFactory.createLoweredBevelBorder();
empty = BorderFactory.createEmptyBorder();

//Simple borders
jComp1.setBorder(blackline);
jComp2.setBorder(raisedbevel);
jComp3.setBorder(loweredbevel);
jComp4.setBorder(empty);

//Matte borders
ImageIcon icon = createImageIcon("images/wavy.gif",
                                 "wavy-line border icon"); //20x22

jComp5.setBorder(BorderFactory.createMatteBorder(
                                   -1, -1, -1, -1, icon));
jComp6.setBorder(BorderFactory.createMatteBorder(
                                    1, 5, 1, 1, Color.red));
jComp7.setBorder(BorderFactory.createMatteBorder(
                                    0, 20, 0, 0, icon));

//Titled borders
TitledBorder title;
title = BorderFactory.createTitledBorder("title");
jComp8.setBorder(title);

title = BorderFactory.createTitledBorder(
		       blackline, "title");
title.setTitleJustification(TitledBorder.CENTER);
jComp9.setBorder(title);

title = BorderFactory.createTitledBorder(
		       loweredetched, "title");
title.setTitleJustification(TitledBorder.RIGHT);
jComp10.setBorder(title);

title = BorderFactory.createTitledBorder(
		       loweredbevel, "title");
title.setTitlePosition(TitledBorder.ABOVE_TOP);
jComp11.setBorder(title);

title = BorderFactory.createTitledBorder(
		       empty, "title");
title.setTitlePosition(TitledBorder.BOTTOM);
jComp12.setBorder(title);

//Compound borders
Border compound;
Border redline = BorderFactory.createLineBorder(Color.red);

//This creates a nice frame.
compound = BorderFactory.createCompoundBorder(
			  raisedbevel, loweredbevel);
jComp13.setBorder(compound);

//Add a red outline to the frame.
compound = BorderFactory.createCompoundBorder(
			  redline, compound);
jComp14.setBorder(compound);

//Add a title to the red-outlined frame.
compound = BorderFactory.createTitledBorder(
			  compound, "title",
			  TitledBorder.CENTER,
			  TitledBorder.BELOW_BOTTOM);
jComp15.setBorder(compound);
</pre></blockquote>

As you probably noticed,
the code uses the <code>BorderFactory</code> class
to create each border.
The <code>BorderFactory</code> class,
which is in the <code>javax.swing</code> package,
returns objects that implement the
<a class="APILink" target="_blank" href="http://java.sun.com/javase/6/docs/api/javax/swing/border/Border.html"><code>Border</code></a> interface.

<p>

The <code>Border</code> interface,
as well as its Swing-provided implementations,
is in the 
<a class="APILink" target="_blank" href="http://java.sun.com/javase/6/docs/api/javax/swing/border/package-summary.html"><code>javax.swing.border</code></a> package.
You often don't need to directly use anything in the border package,
except when specifying constants that are specific 
to a particular border class or when referring to 
the <code>Border</code> type.

</blockquote>
<h3>
<a name="custom">Creating Custom Borders</a>
</h3>
<blockquote>

If <code>BorderFactory</code> doesn't offer you enough control
over a border's form,
then you might need to directly use the API in the border package &#151;
or even define your own border.
In addition to containing the <code>Border</code> interface,
the border package
contains the classes that implement the
borders you've already seen:
<a class="APILink" target="_blank" href="http://java.sun.com/javase/6/docs/api/javax/swing/border/LineBorder.html"><code>LineBorder</code></a>,
<a class="APILink" target="_blank" href="http://java.sun.com/javase/6/docs/api/javax/swing/border/EtchedBorder.html"><code>EtchedBorder</code></a>,
<a class="APILink" target="_blank" href="http://java.sun.com/javase/6/docs/api/javax/swing/border/BevelBorder.html"><code>BevelBorder</code></a>,
<a class="APILink" target="_blank" href="http://java.sun.com/javase/6/docs/api/javax/swing/border/EmptyBorder.html"><code>EmptyBorder</code></a>, 
<a class="APILink" target="_blank" href="http://java.sun.com/javase/6/docs/api/javax/swing/border/MatteBorder.html"><code>MatteBorder</code></a>, 
<a class="APILink" target="_blank" href="http://java.sun.com/javase/6/docs/api/javax/swing/border/TitledBorder.html"><code>TitledBorder</code></a>, and
<a class="APILink" target="_blank" href="http://java.sun.com/javase/6/docs/api/javax/swing/border/CompoundBorder.html"><code>CompoundBorder</code></a>.
The border package also contains a class named 
<a class="APILink" target="_blank" href="http://java.sun.com/javase/6/docs/api/javax/swing/border/SoftBevelBorder.html"><code>SoftBevelBorder</code></a>, which produces a result similar to <code>BevelBorder</code>,
but with softer edges.

<p>

If none of the Swing borders
is suitable, you can implement your own border.
Generally, you do this by creating a subclass