Get Random Key

ImportJava.util.Set;ImportIo.netty.util.internal.ConcurrentSet;/*** Get Key * * @project common-utils * @fileName Getkey.java * @Description *@authorLight-zhang * @date 2018-10-12 17:10:33 *@version1.0.0*/ Public Final classGetKey {Private Static FinalString basedigits = "0123456789abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz-_"; Private Static Final intBASE =basedigits.length (); Private Static Final Char[] Digitschar =Basedigits.tochararray (); Private Static Final intfast_size = ' Z '; Private Static Final int[] Digitsindex =New int[Fast_size + 1]; Static {         for(inti = 0; i < fast_size; i++) {Digitsindex[i]=-1; }         for(inti = 0; i < BASE; i++) {Digitsindex[digitschar[i]]=i; }    }    /*** Parameter decoding * *@paramparamter *@return     */     Public Static Longdecode (String paramter) {Longresult = 0L; synchronized(paramter) {LongMultiplier = 1;  for(intpos = Paramter.length ()-1; POS >= 0; pos--) {result+ = GetIndex (paramter, POS) *multiplier; Multiplier*=BASE; }        }        returnresult; }    /*** Incoming system nanoseconds to prevent duplication * *@paramNumber *@return     */     Public StaticString Encode (Long number) {FinalStringBuilder Builder =NewStringBuilder (); synchronized(number) {if(Number < 0)                NewIllegalArgumentException ("number (BASE64) must be positive:". Concat (Number.tostring ())); if(Number = = 0)                return"0";  while(Number! = 0) {builder.append (digitschar[(int) (number%BASE)]); number/=BASE; }        }        returnbuilder.tostring (); }    Private Static intGetIndex (String paramter,intPmindex) {        Charc =Paramter.charat (Pmindex); if(C >fast_size) {            NewIllegalArgumentException ("Unknow character for Base64:". Concat (paramter)); }        intindex =Digitsindex[c]; if(Index = =-1) {            NewIllegalArgumentException ("Unknow character for Base64:". Concat (paramter)); }        returnindex; }     Public Static voidMain (string[] args) {Set<String> data =NewConcurrentset<string>();  for(inti = 0; i < 20000000; i++) {            //System.out.println (Encode (System.nanotime ()));Data.add (Encode (System.nanotime ())); //System.out.println (Decode (Uuid.randomuuid (). toString ()));} System.out.println (Data.size ()); //System.out.println (Decode ("6c7p6dzh"));    }}

Get Random Key