Expressions are constructed from operands and operators. The operators of an expression indicate which operations to apply to the operands. Examples of operators include
new. Examples of operands include literals, fields, local variables, and expressions.
There are three kinds of operators:
- Unary operators. The unary operators take one operand and use either prefix notation (such as
–x) or postfix notation (such as
- Binary operators. The binary operators take two operands and all use infix notation (such as
- Ternary operator. Only one ternary operator,
?:, exists; it takes three operands and uses infix notation (
The order of evaluation of operators in an expression is determined by the precedence and associativity of the operators (Section 7.2.1).
Operands in an expression are evaluated from left to right. For example, in
F(i) + G(i++) * H(i), method
F is called using the old value of
i, then method
G is called with the old value of
i, and, finally, method
H is called with the new value of
i. This is separate from and unrelated to operator precedence.
Certain operators can be overloaded. Operator overloading permits user-defined operator implementations to be specified for operations where one or both of the operands are of a user-defined class or struct type (Section 7.2.2).