What does the & symbol mean here and whats going on here?

Question

I was going through a java file and saw this block of code and can't really understand what's happening here. What does the & symbol means here and when I run this, I get the values 2 and 8 respectively.
package com.company;

public class Question_2 {

public static void main(String[] args) {
        int mask = 0x000F;
        int value = 0x2222;
        int f = 90;
        int h = 9;
        System.out.println(value & mask);
        System.out.println(f & h);
    }
}

This is The output I get:
2
8

akeempositive · Answer

& is a bit wise operation
& is 1 if both bit at the same position is 1 otherwise 0
Also, to perform this operation, your operands will be converted to base 2
90 = 0101 1010 in base 2
09 = 0000 1001 in base 2
     _________
     0000 1000 which is 8 convert to decimal

000f in hexadecimal =  0000 0000 0000 1111
  2222 in hexadecimal =  0010 0010 0010 0010
  using & on this is     0000 0000 0000 0010 which is 2 convert to decimal

That is how basic & operator works.

ashu · Answer

& is used as a relational operator to check a conditional statement just like && operator.
but there is a small change in how & takes care of conditional statement.  && would first check the first data, if its true then it checks the next one and son on.. but in case of single & character, it just evaluate all conditions even if previous one is a failed one. Thus, any change in the data values due to the conditions will only be reflected in this case.
& can also be used as bitwise operator
println(f & h ) ->
01011010

&   00001001
00001000 -> 8 in decimal

Edik Mkoyan · Answer

& is the bitwise AND operation.
System.out.println(value & mask);

outputs the hex representation of bitwise ANS.
System.out.println(f & h);

outputs the decimal representation of the bitwise AND.
& is smart enough to return the result of the same representation as it's arguments.

Waleed Jubeh · Answer

& refers to Bitwise AND operation.
the mask variable used to enable specific bit and disable the others.
in this code,

System.out.println(value & mask);

the mask keeps the first (from right to left) 4 bits and unsets the others, so always the value of the bitwise AND between the mask variable and any value will be less than 15 because 0x000F -> 0000 0000 0000 1111
mathematically: since the mask is 0x000F if the value of & between the mask and any value is zero then the number is dividable by 16 otherwise it's not dividable by 16

What does the & symbol mean here and whats going on here?

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