Mastering JavaServer Faces 2.2
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EL syntax

In this section, you can see an overview of the main aspects of EL 2.2 and 3.0 syntax. EL supports a handful of operators and reserved words. Each of these are quickly described in the following section (more details are in the EL specification document (http://download.oracle.com/otndocs/jcp/el-3_0-fr-eval-spec/index.html)).

EL operators

EL supports the following categories of operators—arithmetic, relational, logical, conditional, empty and added starting with EL 3.0, string concatenation, assignment and semicolon operators:

EL precedence of operators

Conforming to EL specification, the precedence of operators from the highest to lowest, left to right is as follows:

  • [].
  • () (used to change the precedence of operators)
  • - (unary) not ! empty
  • * / div % mod
  • + - (binary)
  • +=
  • < > <= >= lt gt le ge
  • == != eq ne
  • && and
  • || or
  • ? :
  • -> (lambda expression)
  • =
  • ;

EL reserved words

EL defines the following reserved words:

  • and, or, not, eq, ne, lt, gt, le, ge, true (Boolean literal), false (Boolean literal), null, instanceof (a Java keyword to do a class comparison between objects), empty, div, and mod