Summary of Operators - Java Tutorial 5.0 英文版

The Java^TM Tutorial

Start of Tutorial > Start of Trail > Start of Lesson

Search
Feedback Form

Trail: Learning the Java Language
Lesson: Language Basics

Summary of Operators

The following table lists the operators supported by the Java programming language.

All Operators
Operator Use Description

+ +op Promotes op to int if it's a byte, short, or char

- -op Arithmetically negates op

+ op1 + op2 Adds op1 and op2; also used to concatenate strings

- op1 - op2 Subtracts op2 from op1

* op1 * op2 Multiplies op1 by op2

/ op1 / op2 Divides op1 by op2

% op1 % op2 Computes the remainder of dividing op1 by op2

++ op++ Increments op by 1; evaluates to the value of op before it was incremented

++ ++op Increments op by 1; evaluates to the value of op after it was incremented

-- op-- Decrements op by 1; evaluates to the value of op before it was decremented

-- --op Decrements op by 1; evaluates to the value of op after it was decremented

> op1 > op2 Returns true if op1 is greater than op2

>= op1 >= op2 Returns true if op1 is greater than or equal to op2

< op1 < op2 Returns true if op1 is less than op2

<= op1 <= op2 Returns true if op1 is less than or equal to op2

== op1 == op2 Returns true if op1 and op2 are equal

!= op1 != op2 Returns true if op1 and op2 are not equal

&& op1 && op2 Returns true if op1 and op2 are both true; conditionally evaluates op2

|| op1 || op2 Returns true if either op1 or op2 is true; conditionally evaluates op2

! !op Returns true if op is false

& op1 & op2 Returns true if op1 and op2 are both boolean and both true; always evaluates op1 and op2; if both operands are numbers, performs bitwise AND operation

| op1 | op2 Returns true if both op1 and op2 are boolean and either op1 or op2 is true; always evaluates op1 and op2; if both operands are numbers, performs bitwise inclusive OR operation

^ op1 ^ op2 Returns true if op1 and op2 are different — that is, if one or the other of the operands, but not both, is true

<< op1 << op2 Shifts bits of op1 left by distance op2; fills with 0 bits on the right side

>> op1 >> op2 Shifts bits of op1 right by distance op2; fills with highest (sign) bit on the left side

>>> op1 >>> op2 Shifts bits of op1 right by distance op2; fills with 0 bits on the left side

& op1 & op2 Bitwise AND if both operands are numbers;
conditional AND if both operands are boolean

| op1 | op2 Bitwise OR if both operands are numbers;
conditional OR if both operands are boolean
^ op1 ^ op2 Bitwise exclusive OR (XOR)

~ ~op Bitwise complement

= op1 = op2 Assigns the value of op2 to op1

+= op1 += op2 Equivalent to op1 = op1 + op2

-= op1 -= op2 Equivalent to op1 = op1 - op2

*= op1 *= op2 Equivalent to op1 = op1 * op2

/= op1 /= op2 Equivalent to op1 = op1 / op2

%= op1 %= op2 Equivalent to op1 = op1 % op2

&= op1 &= op2 Equivalent to op1 = op1 & op2

|= op1 |= op2 Equivalent to op1 = op1 | op2

^= op1 ^= op2 Equivalent to op1 = op1 ^ op2

<<= op1 <<= op2 Equivalent to op1 = op1 << op2

>>= op1 >>= op2 Equivalent to op1 = op1 >> op2

>>>= op1 >>>= op2 Equivalent to op1 = op1 >>> op2

?: op1 ? op2 : op3 If op1 is true, returns op2; otherwise, returns op3

[] See Creating and Using Arrays Used to declare arrays, to create arrays, and to access array elements

. See Using Objects Used to form long names

(params) See Defining Methods Delimits a comma-separated list of parameters

(type) (type) op Casts (converts) op to the specified type; an exception is thrown if the type of op is incompatible with type

new See Using Objects and Creating and Using Arrays Creates a new object or array

instanceof op1 instanceof op2 Returns true if op1 is an instance of op2

**All Operators**
Operator	Use	Description
`+`	`+op`	Promotes `op` to `int` if it's a `byte`, `short`, or `char`
`-`	`-op`	Arithmetically negates `op`
`+`	`op1 + op2`	Adds `op1` and `op2`; also used to concatenate strings
`-`	`op1 - op2`	Subtracts `op2` from `op1`
`*`	`op1 * op2`	Multiplies `op1` by `op2`
`/`	`op1 / op2`	Divides `op1` by `op2`
`%`	`op1 % op2`	Computes the remainder of dividing `op1` by `op2`
`++`	`op++`	Increments `op` by 1; evaluates to the value of `op` before it was incremented
`++`	`++op`	Increments `op` by 1; evaluates to the value of `op` after it was incremented
`--`	`op--`	Decrements `op` by 1; evaluates to the value of `op` before it was decremented
`--`	`--op`	Decrements `op` by 1; evaluates to the value of `op` after it was decremented
`>`	`op1 > op2`	Returns `true` if `op1` is greater than `op2`
`>=`	`op1 >= op2`	Returns `true` if `op1` is greater than or equal to `op2`
`<`	`op1 < op2`	Returns `true` if `op1` is less than `op2`
`<=`	`op1 <= op2`	Returns `true` if `op1` is less than or equal to `op2`
`==`	`op1 == op2`	Returns `true` if `op1` and `op2` are equal
`!=`	`op1 != op2`	Returns `true` if `op1` and `op2` are not equal
`&&`	`op1 && op2`	Returns `true` if `op1` and `op2` are both `true`; conditionally evaluates `op2`
`\|\|`	`op1 \|\| op2`	Returns `true` if either `op1` or `op2` is `true`; conditionally evaluates `op2`
`!`	`!op`	Returns `true` if `op` is `false`
`&`	`op1 & op2`	Returns `true` if `op1` and `op2` are both boolean and both `true`; always evaluates `op1` and `op2`; if both operands are numbers, performs bitwise `AND` operation
`\|`	`op1 \| op2`	Returns `true` if both `op1` and `op2` are boolean and either `op1` or `op2` is `true`; always evaluates `op1` and `op2`; if both operands are numbers, performs bitwise inclusive `OR` operation
`^`	`op1 ^ op2`	Returns `true` if `op1` and `op2` are different — that is, if one or the other of the operands, but not both, is `true`
`<<`	`op1 << op2`	Shifts bits of `op1` left by distance `op2`; fills with `0` bits on the right side
`>>`	`op1 >> op2`	Shifts bits of `op1` right by distance `op2`; fills with highest (sign) bit on the left side
`>>>`	`op1 >>> op2`	Shifts bits of `op1` right by distance `op2`; fills with `0` bits on the left side
`&`	`op1 & op2`	Bitwise `AND` if both operands are numbers; conditional `AND` if both operands are boolean
`\|`	`op1 \| op2`	Bitwise `OR` if both operands are numbers; conditional `OR` if both operands are boolean
`^`	`op1 ^ op2`	Bitwise exclusive `OR` (`XOR`)
`~`	`~op`	Bitwise complement
`=`	`op1 = op2`	Assigns the value of `op2` to `op1`
`+=`	`op1 += op2`	Equivalent to `op1 = op1 + op2`
`-=`	`op1 -= op2`	Equivalent to `op1 = op1 - op2`
`*=`	`op1 *= op2`	Equivalent to `op1 = op1 * op2`
`/=`	`op1 /= op2`	Equivalent to `op1 = op1 / op2`
`%=`	`op1 %= op2`	Equivalent to `op1 = op1 % op2`
`&=`	`op1 &= op2`	Equivalent to `op1 = op1 & op2`
`\|=`	`op1 \|= op2`	Equivalent to `op1 = op1 \| op2`
`^=`	`op1 ^= op2`	Equivalent to `op1 = op1 ^ op2`
`<<=`	`op1 <<= op2`	Equivalent to `op1 = op1 << op2`
`>>=`	`op1 >>= op2`	Equivalent to `op1 = op1 >> op2`
`>>>=`	`op1 >>>= op2`	Equivalent to `op1 = op1 >>> op2`
`?:`	`op1 ? op2 : op3`	If `op1` is `true`, returns `op2`; otherwise, returns `op3`
`[]`	See Creating and Using Arrays	Used to declare arrays, to create arrays, and to access array elements
`.`	See Using Objects	Used to form long names
`(`params`)`	See Defining Methods	Delimits a comma-separated list of parameters
`(`type`)`	`(`type`) op`	Casts (converts) `op` to the specified type; an exception is thrown if the type of `op` is incompatible with type
`new`	See Using Objects and Creating and Using Arrays	Creates a new object or array
`instanceof`	`op1 instanceof op2`	Returns `true` if `op1` is an instance of `op2`

Start of Tutorial > Start of Trail > Start of Lesson

Search
Feedback Form