Jakarta ECS - Element Construction Set

Jakarta ECS

As of 2010-09-01, the ECS project is retired. This is an archived site.

Due to a lack of development activity, the Jakarta ECS project has been retired and moved to the Apache Attic. No further ECS development or releases will happen at Jakarta.

Users are encouraged to switch to other techniques for markup generation.

This site is kept online for archiving purposes only.

What is it?

The Element Construction Set is a Java API for generating elements for various markup languages it directly supports HTML 4.0 and XML, but can easily be extended to create tags for any markup language. It is designed and implemented by Stephan Nagy and Jon S. Stevens.

What does it do?

The Element Construction Set allows you to use Java Objects to generate markup code. Gone is the need for writing code that looks like the following:
out.println("<HTML>");
out.println("<HEAD><TITLE>Demo<TITLE><HEAD>");
out.println("<BODY>");
out.println("<H1>Demo Header<H1>");
out.println("<H3>Sub Header:<H3>");
out.println("<FONT SIZE=\"+1\" FACE=\"Times\" COLOR=\"#FFFFFF">);
out.println("The big dog &amp; the little cat chased each other.");
out.println("<FONT>");
out.println("<BODY>");
out.println("<HTML>");
You can do this instead:
Html html = new Html()
              .addElement(new Head()
                  .addElement(new Title("Demo")))
              .addElement(new Body()
              .addElement(new H1("Demo Header"))
              .addElement(new H3("Sub Header:"))
              .addElement(new Font().setSize("+1")
                         .setColor(HtmlColor.WHITE)
                         .setFace("Times")
                         .addElement("The big dog & the little cat chased each other.")));
out.println(html.toString()); 
// or write to the outputstream directly
output(out);
This creates the HTML:
<html><head><title>Demo</title></head><body><h1>Demo Header</h1><h3>Sub Header:</h3>
<font size="+1" color="#FFFFFF" face="Times">The big dog &#38; the little cat chased
 each other.</font></body></html>
Or even easier, use the Document object:
Document doc = (Document) new Document()
              .appendTitle("Demo")
              .appendBody(new H1("Demo Header"))
              .appendBody(new H3("Sub Header:"))
              .appendBody(new Font().setSize("+1")
                         .setColor(HtmlColor.WHITE)
                         .setFace("Times")
                         .addElement("The big dog & the little cat chased each other."));
out.println(doc.toString()); 
// or write to the outputstream directly
output(out);
This creates the same HTML as above.

There are some subtleties in the above code that are worth commenting on.

You don't need to know the Hex value of the color you want. HtmlColor is an interface that defines more than 200 colors.

You don't need to replace & ' " with their entity counterparts, it is done for you (this is configurable of course). ECS gives you the ability to define filters that are applied to the element when you call the addElement() methods.

You can write directly to an elements output stream. output() is a method that can be overridden to provide custom rendering of elements.

ECS also gives you the ability to create your own elements on the fly using the XML element. So you can do the following:
XML my_element = new XML("my_element");

produces:

<my_element></my_element>

Documentation

The javadoc documentation and a TestBed.java file comes with the distribution download. Both resources combined give example code usage that covers every single element. The TestBed.java file is located in the ecs/example directory.

Source

ECS uses the Turbine coding conventions.