求出现重现次数最多的字母，如有多个重复的则都求出来

求出现重现次数最多的字母，如有多个重复的则都求出来

，代码如下：

public class CountChar {
private int[] charCount = new int[26]; // 保存字母出现的次数,初步只统计26个字母（都转换成小写字母）,


private void countChar(String str) {
str = str.toLowerCase();
// 字母a-z的索引

for (char chari = 'a'; chari <= (char) ('a' + 25); chari++) {
for (int i = 0; i < str.length(); i++) {
char ch = str.charAt(i);
if (chari == ch) {
charCount[chari - 'a']++;
}
}
}
}


private char getMaxChar() {
char max = '?';
int maxcount = 0;
for (char chari = 'a'; chari <= (char) ('a' + 25); chari++) {
if (charCount[chari - 'a'] >= maxcount) {
maxcount = charCount[chari - 'a'];
max = chari;
}
}
return max;
}


private int getMaxCount(){
return getMaxChar()=='?'?charCount[getMaxChar()-'a']:-1;
}

public static void main(String[] args) {
String str="aaabab";
CountChar c=new CountChar();
c.countChar(str);
System.out.println(str+":中出现次数最多的字母是：");
System.out.println(c.getMaxChar());
System.out.println("出现次数是：");
System.out.println(c.getMaxCount());
}
}