Data Types
A variable is always of a specific Java
type. Besides the standard Java types for numeric, Boolean, and text
values, the EL provides special support for custom classes developed
according to the JavaBeans guidelines,
java.util.Map
objects,
java.util.List
objects, and arrays.
Bean properties can be accessed using the special property accessor operator (a dot), and be nested to any length:
${aBean.aProperty.aPropertyOfTheProperty.andSoOn}
Map
entries can be accessed the same way:
${aMap.aKey}
List
and array elements can be accessed using the
array accessor operator (square brackets):
${aList[0]} ${anArray[0]} ${anArrayOrList[anExressionWithANumbericValue]}
The array accessor operator can also access bean properties and
Map
entries. It must be used
when the property name is determined by a subexpression, the property
name is a reserved word or contains characters used for operators,
such as a dot:
${aMap[param.customerName]} ${aBean['empty']} ${aMap['com.mycomp.logo']}
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