The Low level discussion of primitive data types and Representations :
byte notation bit notation combinations range
1byte = = 8bit = = pow(2,8) 256 -128 to +127
2byte = = 16bit = = pow(2,8)*pow(2,8) 65536 -32,768 to +32,767
4byte = = 32bit = = pow(2,8)*pow(2,8)*pow(2,8) xxxxxxx xxxxxxxxxxxxxx
8byte = = 64bit = = pow(2,8)*pow(2,8)*pow(2,8)*pow(2,8) xxx xxxxxxxxxxxxx
In java primitive
byte - The
short - The
int - The
long - The
float - The
double - The
char - The
here char is of 16 bit unicode so it's data representation will be in the form of hexadecimal like /uffff
here hexadecimal start with '0' and ends with 'f'
so numberin will be like below
0 - 0
1 - 1
2 - 2
3 - 3
4 - 4
5 - 5
6 - 6
7 - 7
8 - 8
9 - 9
10 -A
11 -B
12 -C
13 -D
14 -E
15 -F
TOTAL numbers from 0 to 15 are 16, means base 16.
char clarification :
Literals of types
below code will give you clarity
code snippet:
char i= '\u0061';
char j= 97;
char k= 'a';
System.out.println(i);
System.out.println((int)i);
System.out.println((char)i);
System.out.println(j);
System.out.println((int)j);
System.out.println((char)j);
System.out.println(k);
System.out.println((int)k);
System.out.println((char)k);
output:
a
97
a
a
97
a
a
97
a
..
..
..
..
To be continued.......
sources:
http://www.binaryhexconverter.com/decimal-to-binary-converter
http://docs.oracle.com/javase/7/docs/api/java/io/DataInput.html
http://en.wikipedia.org/wiki/List_of_Unicode_characters
http://docs.oracle.com/javase/tutorial/java/nutsandbolts/datatypes.html
http://docs.oracle.com/javase/tutorial/i18n/text/string.html***
byte notation bit notation combinations range
1byte = = 8bit = = pow(2,8) 256 -128 to +127
2byte = = 16bit = = pow(2,8)*pow(2,8) 65536 -32,768 to +32,767
4byte = = 32bit = = pow(2,8)*pow(2,8)*pow(2,8) xxxxxxx xxxxxxxxxxxxxx
8byte = = 64bit = = pow(2,8)*pow(2,8)*pow(2,8)*pow(2,8) xxx xxxxxxxxxxxxx
In java primitive
byte - The
byte data type is an 8-bit signed two's complement integer.short - The
short data type is a 16-bit signed two's complement integer.int - The
int data type is a 32-bit signed two's complement integer.long - The
long data type is a 64-bit signed two's complement integer.float - The
float data type is a single-precision 32-bit IEEE 754 floating point.double - The
double data type is a double-precision 64-bit IEEE 754 floating point.char - The
char data type is a single 16-bit Unicode character. It has a minimum value of '\u0000' (or 0) and a maximum value of '\uffff' (or 65,535 inclusive).here char is of 16 bit unicode so it's data representation will be in the form of hexadecimal like /uffff
here hexadecimal start with '0' and ends with 'f'
so numberin will be like below
0 - 0
1 - 1
2 - 2
3 - 3
4 - 4
5 - 5
6 - 6
7 - 7
8 - 8
9 - 9
10 -A
11 -B
12 -C
13 -D
14 -E
15 -F
TOTAL numbers from 0 to 15 are 16, means base 16.
char clarification :
Literals of types
char and String may contain any Unicode (UTF-16) characters. If your editor and file system allow it, you can use such characters directly in your code. If not, you can use a "Unicode escape" such as ' \u0061' ( Latin small letter A)below code will give you clarity
code snippet:
char i= '\u0061';
char j= 97;
char k= 'a';
System.out.println(i);
System.out.println((int)i);
System.out.println((char)i);
System.out.println(j);
System.out.println((int)j);
System.out.println((char)j);
System.out.println(k);
System.out.println((int)k);
System.out.println((char)k);
output:
a
97
a
a
97
a
a
97
a
Value conversions:
From the above code, let us discuss on char 'a'
\u0061 - it is in hexa decimal notation -- 16bit -- 2byte -- pow(2,8)*pow(2,8) -- combinations of 16 bits in binary representation.
0000000001100001 is the Binary representation of character 'a' ( total 16bits) use this link1 or link2 to calculate the value of this binary code.
convert it into decimal like this
0*pow(16,3)+0*pow(16,2)+6*pow(16,1)+1*pow(16,0) = 0+0+6*16+1*1 = 0+0+96+1 = 97
So, 97 is the decimal notation of character 'a'.
..
..
..
To be continued.......
sources:
http://www.binaryhexconverter.com/decimal-to-binary-converter
http://docs.oracle.com/javase/7/docs/api/java/io/DataInput.html
http://en.wikipedia.org/wiki/List_of_Unicode_characters
http://docs.oracle.com/javase/tutorial/java/nutsandbolts/datatypes.html
http://docs.oracle.com/javase/tutorial/i18n/text/string.html***
