Difference Between & and && in Java

In this section, we will discuss the two most important operators & and && in Java and also see the key differences between logical and bitwise operators along with its uses.

& Operator

The single AND operator (&) is known as the Bitwise AND operator. It operates on a single bit. It takes two operands. A bit in the result is 1 if and only if both of the corresponding bits in the operands are 1. The result of the operator may be any number. For example:

a = 01100010

b = 10111010

a&b = 00100010

&& Operator

The double AND operators (&&) are known as logical AND operators. It is usually used in loops and conditional statements. It is usually used in Boolean expressions. The result of && is always 0 or 1.

Difference Between & and &&

The key difference between && and & operators is that && supports short-circuit evaluations while & operator does not.

Another difference is that && will evaluate the expression exp1, and immediately return a false value if exp1 is false. While & operator always evaluates both expressions (exp1 and exp2) before retiring an answer.

S.N.	Basis	& Operator	&& Operator
1	Operator	It is a bitwise AND operator.	It is a logical AND operator.
2	Evaluation	It evaluates both the left and right side of the given expression.	It only evaluates the left sides of the given expression.
3	Operates on	It operates on Boolean data types as well as on bits.	It operates only on Boolean datatype.
4	Uses	Used to check logical condition and also used to mask off certain bits such as parity bits.	Used only to check the logical conditions.
5	Example	z = x & y	if (y > 1 && y > x)

Let's understand bitwise and logical and operator through a Java program.

LogicalAndExample.java

public class LogicalAndExample
{
public static void main(String args[]) 
{
int a=10, b=20;
if (a == 10 && b == 20)
System.out.println("true");
else
System.out.println("false");
int c=78, d=90;
if (a > c && b < d)
System.out.println("true");
else
System.out.println("false");
}
}

Output:

true
false

BitwiseAndExample.java

public class BitwiseAndExample
{
public static void main(String args[])
{
int a = 3;
int b = 9;
//bitwise AND
System.out.println("a&b = " + (a & b));
}
} 

Output:

a&b=1

Let's create another Java program and use Logical and Bitwise AND operators simultaneously.

JavaOperators.java

public class JavaOperators 
{
public static void main(String args[]) 
{
int a = 58; //58 in binary is 111010
int b = 13; //13 in binary is 1101
System.out.println(a&b);  //returns 8 = 1000
int x = 10;
System.out.println(x<30 && x<60);  //returns false
}
}

Output: