Basic data type data in Java converted to byte[] array storage

Basic data type data in Java converted to byte[] array storage

1  Packagecom.wocqz.test;2 3  Public classTestbyte {4 5     /**6 * int turns into a byte array7      * */8      Public Static  byte[] Int_byte (intID) {9         //Int is a 32-bit 4 byte creates a byte array of length 4Ten         byte[] arr=New byte[4]; One          AArr[0]= (byte) ((id>>0*8) &0xff); -Arr[1]= (byte) ((id>>1*8) &0xff); -Arr[2]= (byte) ((id>>2*8) &0xff); theArr[3]= (byte) ((id>>3*8) &0xff); -          -         returnarr; -     } +      -     /** + * byte array reversed int A      * */ at      Public Static intByte_int (byte[] arr) { -          -         intI0= (int) ((ARR[0]&AMP;0XFF) <<0*8); -         intI1= (int) ((ARR[1]&AMP;0XFF) <<1*8); -         intI2= (int) ((ARR[2]&AMP;0XFF) <<2*8); -         intI3= (int) ((ARR[3]&AMP;0XFF) <<3*8); in          -         returni0+i1+i2+i3; to     } +      -      Public Static voidMain (string[] args) { the          *         byte[] Int_byte = Testbyte.int_byte (10); $         Panax Notoginseng          for(byteb:int_byte) { -System.out.println ("------->" +b); the         } +          A          the         intByte_int =Testbyte.byte_int (int_byte); +System.out.println ("<----------" +byte_int); -          $     } $}

Let's go first. &x0ff 16 binary to binary is 11111111

& Bitwise AND operator
Two operand median is 1 and result is 1
If two operations are bit one 1 another 0, the result is 0
That is, the arithmetic rule:0&0=0; 0&1=0; 1&0=0; 1&1=1;

Here the main role is to clear 0, take a number of the middle finger positioning
When we convert the ID into binary, we can move a few 8 bits to the X0FF on & and we can get the byte binary in the binary  is converted into a binary stored in a byte array regardless of type of int type long


(Self-understanding--------------------------------------------------------------------------------------------------not to spray)

Basic data type data in Java converted to byte[] array storage