EL expressions use the syntax ${expr}. For example,

<element attr1=”${bean.property}”.../>
${map[entry]}
<another-element>${3+counter} is ${empty map}</another-element>

When an EL expression is used as an attribute value, it could return any kind of objects as long as the component accepts it. For example, the following expression will be evaluated to a Boolean object.

<window if="${some > 10}">