Displacement algorithm to determine whether element exists

Package com. yanfan. test;


Import java. util. ArrayList;
Import org. apache. commons. lang. StringUtils;


Public class Test_Binary {


Public static void main (String [] args) throws Exception {
Long l = toLongFlag ");
System. out. println (l );
String str = toStrFlag (l );
System. out. println (str );
System. out. println ("Whether the values of 11,12, 13,14 are in the range :"
+ ContainFlag (l, "11,12, 13,22, 23 "));
}


/**
* Convert the number list to the displacement number.
*/
Public static long toLongFlag (String flag) throws Exception {
Long result = 0;
If (StringUtils. isBlank (flag )){
Throw new Exception ("please pass the number List ");
}
String [] flags = flag. split (",");
For (String e: flags ){
If (StringUtils. isNotBlank (e )){
E = e. trim ();
Int item = Integer. parseInt (e );
If (item> 31 ){
Throw new Exception ("This method supports a maximum of 31 bits, so please pass a number below 31 ");
}
Long l = 1 <(item-1 );
Result = result | l;
}
}
Return result;
}


/**
* Convert the displacement quantity to a number list.
*/
Public static String toStrFlag (long v ){
ArrayList List = new ArrayList ();
Char [] cs = Long. toBinaryString (v). toCharArray ();
For (int I = cs. length-1; I> = 0; I --){
If (cs [I] = '1 '){
List. add (cs. length-I );
}
}
Return StringUtils. join (list ,',');
}


/**
* Determines whether a number list exists in a specified displacement number.
*/
Public static boolean containFlag (long flags, String props) throws Exception {
Long rep = toLongFlag (props );
Rep = flags | rep;
If (rep = flags ){
Return true;
} Else {
Return false;
}
}


}