Java - Basic OperatorsJava provides a rich set of operators to manipulate variables. We can divide all the Java operators into the following groups:
Arithmetic operators are used in mathematical expressions in the same way that they are used in algebra. The following table lists the arithmetic operators: Assume integer variable A holds 10 and variable B holds 20, then:
The following simple example program demonstrates the arithmetic operators. Copy and paste the following Java program in Test.java file and compile and run this program:
public class Test{
public static void main(String args[]){ int a =10; int b =20; int c =25; int d =25; b = "+(a + b)); System.out.println("a + System.out.println("a - b = "+(a - b)); System.out.println("a * b = "+(a * b)); System.out.println("b / a = "+(b / a)); System.out.println("b % a = "+(b % a)); System.out.println("c % a = "+(c % a)); System.out.println("a++ = "+(a++)); System.out.println("b-- = "+(a--)); // Check the difference in d++ and ++d System.out.println("d++ = "+(d++)); System.out.println("++d = "+(++d)); } } This would produce the following result:
+ b =30
- b =-10 * b =200 / a =2 % a =0 % a =5 a++=10 b--=11 d++=25 ++d =27 The Relational Operators: There are following relational operators supported by Java language: Assume variable A holds 10 and variable B holds 20, then:
The following simple example program demonstrates the relational operators. Copy and paste the following Java program in Test.java file and compile and run this program. :
public class Test{
public static void main(String args[]){ int a =10; int b =20; System.out.println("a == b = "+(a == b)); System.out.println("a != b = "+(a != b)); System.out.println("a > b = "+(a > b)); System.out.println("a < b = "+(a < b)); System.out.println("b >= a = "+(b >= a)); System.out.println("b <= a = "+(b <= a)); } } This would produce the following result:
a == b =false
a != b =true a > b =false a < b =true b >= a =true b <= a =false TheBitwiseOperators: Java defines several bitwise operators, which can be applied to the integer types, long, int, short, char, and byte. Bitwise operator works on bits and performsbit-by-bit operation. Assume if a = 60; and b = 13; now in binary format they will be as follows: a = 0011 1100 b = 0000 1101 ----------------- a&b = 0000 1100 a|b = 0011 1101 a^b = 0011 0001 ~a = 1100 0011 The following table lists the bitwise operators: Assume integer variable A holds 60 and variable B holds 13, then:
The following simple example program demonstrates the bitwise operators. Copy and paste the following Java program in Test.java file and compile and run this program:
public class Test{
public static void main( String args[]){ int a =60; /* 60 = 0011 1100 */ int b =13; /* 13 = 0000 1101 */ int c =0; c = a & b;/* 12 = 0000 1100 */ System.out.println("a & b = "+ c ); c = a | b;/* 61 = 0011 1101 */ System.out.println("a | b = "+ c ); c = a ^ b;/* 49 = 0011 0001 */ System.out.println("a ^ b = "+ c ); c =~a;/*-61 = 1100 0011 */ System.out.println("~a = "+ c ); c = a <<2;/* 240 = 1111 0000 */ System.out.println("a << 2 = "+ c ); c = a >>2;/* 215 = 1111 */ System.out.println("a >> 2 = "+ c ); c = a >>>2;/* 215 = 0000 1111 */ System.out.println("a >>> 2 = "+ c ); } } This would produce the following result:
a & b =12
a | b =61 a ^ b =49 ~a =-61 a <<2=240 a >>15 a >>>15 The Logical Operators: The following table lists the logical operators: Assume Boolean variables A holds true and variable B holds false, then:
The following simple example program demonstrates the logical operators. Copy and paste the following Java program in Test.java file and compile and run this program:
public class Test{
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)); } } This would produce the following result:
a && b =false
a || b =true !(a && b)=true The Assignment Operators: There are following assignment operators supported by Java language:
The following simple example program demonstrates the assignment operators. Copy and paste the following Java program in Test.java file and compile and run this program:
public class Test{
public static void main(String args[]){ int a =10; int b =20; int c =0; c = a + b; System.out.println("c = a + b = "+ c ); c += a ; System.out.println("c += a = "+ c ); c -= a ; System.out.println("c -= a = "+ c ); c *= a ; System.out.println("c *= a = "+ c ); a =10; c =15; c /= a ; System.out.println("c /= a = "+ c ); a =10; c =15; c %= a ; System.out.println("c %= a = "+ c ); c <<=2; System.out.println("c <<= 2 = "+ c ); c >>=2; System.out.println("c >>= 2 = "+ c ); c >>=2; System.out.println("c >>= a = "+ c ); c &= a ; System.out.println("c &= 2 = "+ c ); c ^= a ; System.out.println("c ^= a = "+ c ); c |= a ; System.out.println("c |= a = "+ c ); } } This would produce the following result:
c = a + b =30
c += a =40 c -= a =30 c *= a =300 c /= a =1 c %= a =5 c <<=2=20 c >>=2=5 c >>=2=1 c &= a =0 c ^= a =10 c |= a =10 Misc Operators There are few other operators supported by Java Language. Conditional Operator (?:): Conditional operator is also known as the ternary operator. This operator consists of three operands and is used to evaluate Boolean expressions. The goal of the operator is to decide which value should be assigned to the variable. The operator is written as:
variable x =(expression)? value iftrue: value iffalse
Following is the example:
public class Test{
public static void main(String args[]){ int a , b; a=10; b=(a ==1)?20:30; System.out.println("Value of b is : "+ b ); System.out.println("Value of b is : "+ b ); } } This would produce the following result:
Value of b is:30
Value of b is:20 instanceof Operator: This operator is used only for object reference variables. The operator checks whether the object is of a particular type(class type or interface type). instanceof operator is wriiten as:
(Object reference variable ) instanceof (class/interface type)
If the object referred by the variable on the left side of the operator passes the IS-A check for the class/interface type on the right side, then the result will be true. Following is the example:
String name = “James”;
boolean result = name instanceof String; // This will return true since name is type of String This operator will still return true if the object being compared is the assignment compatible with the type on the right. Following is one more example:
classVehicle{}
public class CarextendsVehicle{ public static void main(String args[]){ Vehicle a =newCar(); boolean result = a instanceofCar; System.out.println(result); } } This would produce the following result:
true
Precedence of Java Operators: Operator precedence determines the grouping of terms in an expression. This affects how an expression is evaluated. Certain operators have higher precedence than others; for example, the multiplication operator has higher precedence than the addition operator: For example, x = 7 + 3 * 2; here, x is assigned 13, not 20 because operator * has higher precedence than +, so it first gets multiplied with 3*2 and then adds into 7. Here, operators with the highest precedence appear at the top of the table, those with the lowest appear at the bottom. Within an expression, higher precedence operators will be evaluated first.
Next chapter would explain about loop control in Java programming. The chapter will describe various types of loops and how these loops can be used in Java program development and for what purposes they are being used. |
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