Custom tags are a very useful feature of JSF. They are demonstrated in the planets example which can be run here. This example defines a <corejsf:planet> tag that is used for each of the planet buttons. Each use of the tag specifies three attributes:

• name
• image
• label

Use of the custom tags technology involves doing four things:

• Use Custom Tags
• Define Custom Tags
• Define a Tag Library
• Register the Tag Library

• The planet images in the sidebar page sidebar.xhtml act as links to the individual planet content pages
• Each link is created with a custom corejsf:planet tag with attributes:
• The corejsf tag namespace and prefix must be declared just like the others

Web Pages/sections/planetarium/sidebar.xhtml

A <ui:composition> tag is used to define a custom tag. The attributes of the new tag are defined just by being mentioned in Expression Language markup. In a <corejsf:planet> tag

• The name attribute specifies the name that identifies the planet. This name is used Planetarium.java methods.
• The image attribute specifies the file for the planet image.
• The label attribute specifies the label that appears under the planet image.

The <h:commandLink> tag with a graphics image acts just like a <h:commandButton>. Its appearance is controlled using an EL conditional expression to determine the style class. This makes the background color lighter if the planet is selected.

Web Pages//WEB-INF/tags/corejsf/planet.xhtml