Operaterji Java: aritmetični, relacijski, logični in še več

V tej vadnici boste s pomočjo primerov spoznali različne vrste operaterjev v Javi, njihovo sintakso in kako jih uporabljati.

Operatorji so simboli, ki izvajajo operacije nad spremenljivkami in vrednostmi. Na primer, +je operator, ki se uporablja za seštevanje, medtem ko *je tudi operator, ki se uporablja za množenje.

Operaterje v Javi lahko razvrstimo v 5 vrst:

  1. Aritmetični operaterji
  2. Operatorji dodelitve
  3. Relacijski operaterji
  4. Logični operaterji
  5. Unary Operators
  6. Bitni operaterji

1. Aritmetični operaterji Java

Aritmetični operatorji se uporabljajo za izvajanje aritmetičnih operacij nad spremenljivkami in podatki. Na primer

 a + b;

Tu +uporabimo operator za dodajanje dveh spremenljivk a in b. Podobno obstajajo v Javi različni drugi aritmetični operaterji.

Operater Delovanje
+ Dodatek
- Odštevanje
* Množenje
/ Divizija
% Modulo Operation (Preostanek po delitvi)

Primer 1: Aritmetični operatorji

 class Main ( public static void main(String() args) ( // declare variables int a = 12, b = 5; // addition operator System.out.println("a + b = " + (a + b)); // subtraction operator System.out.println("a - b = " + (a - b)); // multiplication operator System.out.println("a * b = " + (a * b)); // division operator System.out.println("a / b = " + (a / b)); // modulo operator System.out.println("a % b = " + (a % b)); ) )

Izhod

 a + b = 17 a - b = 7 a * b = 60 a / b = 2 a% b = 2

V zgornjem primeru smo uporabili +, -in *operatorje za izračun operacij seštevanja, odštevanja in množenja.

/ Operater oddelka

Upoštevajte postopek a / bv našem programu. /Operater je operater delitev.

Če uporabimo delitveni operater z dvema celo številoma, bo tudi nastali količnik celo število. In če je eden od operandov število s plavajočo vejico, bomo dobili, da bo rezultat tudi v plavajoči vejici.

 In Java, (9 / 2) is 4 (9.0 / 2) is 4.5 (9 / 2.0) is 4.5 (9.0 / 2.0) is 4.5

% Modulo Operator

Operator modula %izračuna preostanek. Ko a = 7je deljeno z b = 4, je preostanek 3 .

Opomba : %Operator se uporablja predvsem s celimi števili.

2. Operaterji dodelitve Java

Operatorji dodelitve se v Javi uporabljajo za dodelitev vrednosti spremenljivkam. Na primer

 int age; age = 5;

Tukaj =je operater dodelitve. Vrednost na desni dodeli spremenljivki na levi. To pomeni, da je 5 spremenljivi starosti.

Poglejmo še nekaj operaterjev dodelitve, ki so na voljo v Javi.

Operater Primer Enakovreden
= a = b; a = b;
+= a += b; a = a + b;
-= a -= b; a = a - b;
*= a *= b; a = a * b;
/= a /= b; a = a / b;
%= a %= b; a = a % b;

Primer 2: Operatorji dodelitve

 class Main ( public static void main(String() args) ( // create variables int a = 4; int var; // assign value using = var = a; System.out.println("var using =: " + var); // assign value using =+ var += a; System.out.println("var using +=: " + var); // assign value using =* var *= a; System.out.println("var using *=: " + var); ) )

Izhod

 var using =: 4 var using + =: 8 var using * =: 32

3. Java relacijski operaterji

Relacijski operatorji se uporabljajo za preverjanje razmerja med dvema operandoma. Na primer

 // check is a is less than b a < b;

Tu je >operator relacijski operater. Preveri, ali je a manj kot b ali ne.

Vrne se bodisi trueoz false.

Operater Opis Primer
== Je enako 3 == 5vrne false
!= Ni enako 3 != 5vrne true
> Večji kot 3> 5vrne false
< Manj kot 3 < 5vrne true
>= Večji ali enak 3>= 5vrne false
<= Manj ali enako 3 <= 5vrne false

Primer 3: Relacijski operaterji

 class Main ( public static void main(String() args) ( // create variables int a = 7, b = 11; // value of a and b System.out.println("a is " + a + " and b is " + b); // == operator System.out.println(a == b); // false // != operator System.out.println(a != b); // true //> operator System.out.println(a> b); // false // < operator System.out.println(a = operator System.out.println(a>= b); // false // <= operator System.out.println(a <= b); // true ) )

Opomba : Relacijski operaterji se uporabljajo pri odločanju in zankah.

4. Java logični operaterji

Logični operatorji se uporabljajo za preverjanje, ali je izraz trueoz false. Uporabljajo se pri odločanju.

Operater Primer Pomen
&& (Logično IN) expression1 && expression2 true only if both expression1 and expression2 are true
|| (Logical OR) expression1 || expression2 true if either expression1 or expression2 is true
! (Logical NOT) !expression true if expression is false and vice versa

Example 4: Logical Operators

 class Main ( public static void main(String() args) ( // && operator System.out.println((5> 3) && (8> 5)); // true System.out.println((5> 3) && (8 < 5)); // false // || operator System.out.println((5 5)); // true System.out.println((5> 3) || (8 < 5)); // true System.out.println((5 < 3) || (8 3)); // false ) )

Working of Program

  • (5> 3) && (8> 5) returns true because both (5> 3) and (8> 5) are true.
  • (5> 3) && (8 < 5) returns false because the expression (8 < 5) is false.
  • (5> 3) || (8> 5) returns true because the expression (8> 5) is true.
  • (5> 3) && (8> 5) returns true because the expression (5> 3) is true.
  • (5> 3) && (8> 5) returns false because both (5 < 3) and (8 < 5) are false.
  • !(5 == 3) returns true because 5 == 3 is false.
  • !(5> 3) returns false because 5> 3 is true.

5. Java Unary Operators

Unary operators are used with only one operand. For example, ++ is a unary operator that increases the value of a variable by 1. That is, ++5 will return 6.

Different types of unary operators are:

Operator Meaning
+ Unary plus: not necessary to use since numbers are positive without using it
- Unary minus: inverts the sign of an expression
++ Increment operator: increments value by 1
-- Decrement operator: decrements value by 1
! Logical complement operator: inverts the value of a boolean

Increment and Decrement Operators

Java also provides increment and decrement operators: ++ and -- respectively. ++ increases the value of the operand by 1, while -- decrease it by 1. For example,

 int num = 5; // increase num by 1 ++num;

Here, the value of num gets increased to 6 from its initial value of 5.

Example 5: Increment and Decrement Operators

 class Main ( public static void main(String() args) ( // declare variables int a = 12, b = 12; int result1, result2; // original value System.out.println("Value of a: " + a); // increment operator result1 = ++a; System.out.println("After increment: " + result1); System.out.println("Value of b: " + b); // decrement operator result2 = --b; System.out.println("After decrement: " + result2); ) )

Output

 Value of a: 12 After increment: 13 Value of b: 12 After decrement: 11

In the above program, we have used the ++ and -- operator as prefixes (++a, --b). We can also use these operators as postfix (a++, b++).

There is a slight difference when these operators are used as prefix versus when they are used as a postfix.

To learn more about these operators, visit increment and decrement operators.

6. Java Bitwise Operators

Bitwise operators in Java are used to perform operations on individual bits. For example,

 Bitwise complement Operation of 35 35 = 00100011 (In Binary) ~ 00100011 ________ 11011100 = 220 (In decimal)

Here, ~ is a bitwise operator. It inverts the value of each bit (0 to 1 and 1 to 0).

The various bitwise operators present in Java are:

Operator Description
~ Bitwise Complement
<< Left Shift
>> Right Shift
>>> Unsigned Right Shift
& Bitwise AND
^ Bitwise exclusive OR

These operators are not generally used in Java. To learn more, visit Java Bitwise and Bit Shift Operators.

Other operators

Besides these operators, there are other additional operators in Java.

Java instanceof Operator

The instanceof operator checks whether an object is an instanceof a particular class. For example,

 class Main ( public static void main(String() args) ( String str = "Programiz"; boolean result; // checks if str is an instance of // the String class result = str instanceof String; System.out.println("Is str an object of String? " + result); ) )

Output

 Is str an object of String? true

Here, str is an instance of the String class. Hence, the instanceof operator returns true. To learn more, visit Java instanceof.

Java Ternary Operator

The ternary operator (conditional operator) is shorthand for the if-then-else statement. For example,

 variable = Expression ? expression1 : expression2

Here's how it works.

  • If the Expression is true, expression1 is assigned to the variable.
  • If the Expression is false, expression2 is assigned to the variable.

Let's see an example of a ternary operator.

 class Java ( public static void main(String() args) ( int februaryDays = 29; String result; // ternary operator result = (februaryDays == 28) ? "Not a leap year" : "Leap year"; System.out.println(result); ) )

Output

 Leap year

In the above example, we have used the ternary operator to check if the year is a leap year or not. To learn more, visit the Java ternary operator.

Zdaj, ko poznate operaterje Java, je čas, da veste tudi o vrstnem redu ocenjevanja operaterjev. Če želite izvedeti več, obiščite Java Operator Precedence.

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