The Java Boutique: Java Tutorial: Poor Man's Graphics

Tutorials : Poor Man's Graphics :

Contents

Using Javabeans to Produce the Bars

Now that we have the basic technique in place we can write a JavaBean which facilitates making the bars. For a single horizontal bar we need a method like this (the parameters should in this case be self-explanatory):

public String getHbar(int length, int width,
  String color, String label)

[The lines above are one line. It has been split for formatting purposes.]

And for the vertical bar we need this method:

public String getVbar(int length, int width, String color, String label)

These methods simply return the HTML for a single bar.

At the same time we'll add a possibility to define the font family and size for the chart. To adhere to common standards we'll use a style sheet definition. To set the font information and to retrieve the style sheet we need methods like this:

public void setCSS(String fontFamily, String fontSize)
public String getCSS()

You can find the code for the JavaBean here. A JSP-page which uses the bean is this:

<jsp:useBean id="graph" class="htmlgraph.Graph" scope="request" />
<%
graph.setCSS("Verdana","10px");
%>
<html>
<head>
<%=graph.getCSS()%>
</head>
<body>
<table
cellspacing=0 cellpadding=1 border=0>
<tr><%=graph.getHbar(300,10,"red","NBC")%></tr>
<tr><%=graph.getHbar(200,10,"green","CBS")%></tr>
<tr><%=graph.getHbar(320,10,"orange","CNN")%></tr>
</table>

<table cellspacing=0 cellpadding=1 border=0>
<tr>
<%=graph.getVbar(75,20,"red","ASP")%>
<%=graph.getVbar(87,20,"green","JSP")%>
<%=graph.getVbar(45,20,"orange","EJB")%>
<%=graph.getVbar(10,20,"black","CGI")%>
</tr>
</table>
</body>
</html>

This will produce these bars:

Note that by changing the values for cellspacing and cellpadding you can fine-tune the layout of the bars.

Applet Index
(sorted alphabetically)
A B C D E F G H I J K
L M N O P Q R S T U
V W X Y Z #s

The Java Source
(applets w/source code)
A B C D E F G H I J K
L M N O P Q R S T U
V W X Y Z

How to Add Java Applets to Your Site

New on the Java Boutique:

New Review:

Time Management Made Easy with the Quartz Enterprise Job Scheduler
Why not just use the Java timer API? This open source scheduling API boasts simplicity, ease-of-integration, a well-rounded feature set, and it's free!

New Applet:

Reverse Complement
Reverse Complement is a simple applet that converts DNA or RNA sequences into three useful formats.