Java BASIC Syntax---java operators

Java BASIC Syntax---java operators 0. Overview

The operators in Java are mainly divided into the following types:

• Arithmetic operators
• Assignment operators
• Relational operators
• logical operators
• Conditional operators
• Bitwise operators
• Other operators

1. Arithmetic operators /tr>

operator	description
+	addition, two numbers on both sides of the plus sign add
-	subtraction, minus the number to the left minus the number on the right
*	multiplication, multiply two numbers on both sides of the multiplication sign
/	Division, Division sign the number on the left divided by the number on the right
%	modulo. The remainder of the left divided by the number on the right
+ +	increment, the value of the operand increased by 1
--< /td>	decrement, operand value minus 1

public class Arithmetictest {public static void main (string[] args) {double number1 = 12.390;        Double number2 = 74.340;        int number3 = 4;        System.out.println (number2 + "+" + number1 + "=" + (number2 + number1));        System.out.println (number2 + "-" + number1 + "=" + (number2-number1));        System.out.println (number1 + "*" + number3 + "=" + (Number1 * number3));        System.out.println (number2 + "/" + number1 + "=" + (number2/number1));        System.out.println (number1 + "%" + number3 + "=" + (float) (number1% number3));        int number4 = 5;        int number5 = 5;        int number = number4++;        System.out.println ("number4++ =" + number + ", Number4 =" + Number4);        Number = ++number5;        System.out.println ("++NUMBER5 =" + number + ", Number5 =" + Number5);        System.out.println ("(number++) =" + (number++));;    System.out.println ("(number--) =" + (number--)); }}output:74.34 + 12.39 =86.73 74.34-12.39 = 61.95 12.39 * 4 = 49.56 74.34/12.39 = 6.0 12.39% 4 = 0.39 number4++ = 5, Number4 = 6 ++number5 = 6, Number5 = 6 (number++) = 6 (number--) = 7

2. Assignment operators

operator	Description	Example
=	A simple assignment operator that assigns the value of the right operand to the operand on the left	c = A+b assigns the value of A+b to C
+ =	Add and assign operators, which add the left and right operands to the left operand	c + = A is equivalent to C = C + A
-=	Minus and assignment operators, which subtract left and right operands to the left operand	C-= A is equivalent to C = c-a
*=	Multiply and assign operators, which multiply the left and right operands by assigning the left operand the value of	c * = A is equivalent to C = c * A
/=	In addition to the assignment operator, it assigns the left operand and the right operand to the left operand by dividing the number of	c/= A is equivalent to C = c/a
(%)=	Modulo and assignment operators, which take the left operand and the right operand to the left operand after modulo	c%= A is equivalent to C = c%a
<<=	Left Shift assignment operator	c << = 2 equivalent to C = C << 2
>>=	Right Shift assignment operator	c >> = 2 equivalent to C = C >> 2
&=	Bitwise-and-assignment operators	C&= 2 is equivalent to C = c&2
^=	Bitwise XOR or assignment operator	c ^ = 2 equivalent to C = c ^ 2
|=	Bitwise OR Assignment operators	C | = 2 equivalent to C = C | 2

public class AssignmentTest {    public static void main(String[] args) {        int a = 100;        int b = 200;        int c = 4;        System.out.println("a (a += b) = " + (a += b));        System.out.println("a (a -= 100) = " + (a -= 100));        System.out.println("a (a *= c) = " + (a *= c));        System.out.println("a (a /= 100) = " + (a /= 100));        System.out.println("a (a %= 100) = " + (a %= 100));        System.out.println("c ( c<<2 ) = " + ( c << 2 ));        System.out.println("c ( c>>2 ) = " + ( c >> 2 ));            }}Output：    a (a += b) = 300    a (a -= 100) = 200    a (a *= c) = 800    a (a /= 100) = 8    a (a %= 100) = 8    c ( c<<2 ) = 16    c ( c>>2 ) = 1

3. Relational operators

operator	description
==	Checks if the values of the two operands are equal, and if they are equal, the condition is true.
! =	Checks if the values of the two operands are equal, the condition is true if the values are not equal.
;	checks if the value of the left operand is greater than the right-operand value, if so the condition is true.
<	checks if the value of the left operand is less than the right-operand value, if so the condition is true.
>=	checks if the value of the left operand is greater than or equal to the value of the right operand, if so the condition is true.
<=	checks whether the value of the left operand is less than or equal to the value of the right operand, if so the condition is true.

public class RelationalTest {    public static void main(String[] args) {        int a = 100;        int b = 88;        System.out.println("(a == b) = " + (a == b ));        System.out.println("(a != b) = " + (a != b ));        System.out.println();        System.out.println("(a <= b) = " + (a <= b ));        System.out.println("(a >= b) = " + (a >= b ));        System.out.println();        System.out.println("(a > b) = " + (a > b ));        System.out.println("(a < b) = " + (a < b ));    }}Output：    (a == b) = false    (a != b) = true    (a <= b) = false    (a >= b) = true    (a > b) = true    (a < b) = false

4. Logical operators The

operator	description
&&	is called a logical AND operator. The condition is true when and only if two operands are true.
| |	is called a logical OR operator. If any one of the two operands is true, the condition is true.
!	is called a logical non-operator. The logical state used to reverse the operand. If the condition is true, the logical non-operator will get false.

public class LogicalTest {    public static void main(String[] args) {        boolean a = true;        boolean b = false;        System.out.println("(a && b) = " + (a && b));        System.out.println("(a || b) = " + (a || b));        System.out.println("!(a && b) = " + !(a && b));        //短路逻辑运算符&&：先判断前一个条件，true则执行第二个判断操作，为false则不在执行        int c = 100;        System.out.println((c > 100) && (c++ < 150));        System.out.println("c = "  + c);        System.out.println();        System.out.println((c++ < 150) && (c > 100));        System.out.println("c = "  + c);    }}Output：    (a && b) = false    (a || b) = true    !(a && b) = true    false    c = 100    true    c = 101

5. Conditional operators

Operator has 3 operands, you need to determine the value of a Boolean expression. The main decision of the operator is to decide which value should be assigned to the variable.

Eg:a = (b = = 1)? 20:30;

This statement: first to determine whether B is 1, true to set A to 20, false to set B to 30;

public class ConditionalTest {    public static void main(String[] args) {        int a;        int b = 100;        a = (b == 100) ? 66 : 88;        System.out.println("a =" + a);        System.out.println();        b = (a == 66) ? 888 : 88;        System.out.println("b =" + b);    }}Output：a =66b =888

6. Case studies

Determines whether the year entered is a leap years;

Leapyear: A year that can be divisible by 400 and divisible by 4 but not divisible by 100

public class LeapYearDemo {    //LeapYear:能被400整除的年份和能被4整除但是不能被100整除的年份    public static void main(String[] args) {        System.out.println("请输入要判断的年份： ");        Scanner sc = new Scanner(System.in);        int year = sc.nextInt();        if ((year % 400 == 0) || (year % 4 == 0 && year %100 != 0 ))        {            System.out.println(year + "是闰年！");        }        else        {            System.out.println(year + "不是闰年！");        }    }}Output：    请输入要判断的年份：     1997    1997不是闰年！        请输入要判断的年份：     2020    2020是闰年！

Java BASIC Syntax---java operators