In addition to the . and  operators discussed in Value and Method Expressions, the JSP expression language provides the following operators, which can be used in rvalue expressions only:
Arithmetic: +, - (binary), *, / and div, % and mod, - (unary)
Logical: and, &&, or, ||, not, !
Relational: ==, eq, !=, ne, <, lt, >, gt, <=, ge, >=, le. Comparisons can be made against other values, or against boolean, string, integer, or floating point literals.
Empty: The empty operator is a prefix operation that can be used to determine whether a value is null or empty.
Conditional: A ? B : C. Evaluate B or C, depending on the result of the evaluation of A.
The precedence of operators 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