JAVA 高效判断字符串的字符个数

public static void main(String[] args) {

int max = 0;

int[] count = new int[255];

char ch;

String input = "QEQSERTWR145657ABCsfgsdEYP[YLYULYfgDEFsdgfsgtutjtyktEDYERTYEEAERYTEYERALUILYUILO";

for(int i = 0; i < input.length(); i++) {

int cou = ++count[(int)input.charAt(i)];

if(cou >= max) {

max = cou;

ch = input.charAt(i);

}

}

for(int i=0;i<count.length;i++){

if(count[i]==0) continue;

System.out.println(String.valueOf((char)i)+" "+count[i]);

}

}