String string = "abcjkdjfkjdkfddd";
char[] content = string.toCharArray();
Map<Character, Integer> map = new HashMap<Character, Integer>();
for (int i = 0; i < content.length; i++) {
if (map.get(content[i]) != null) {
map.put(content[i], map.get(content[i]) + 1);
} else {
map.put(content[i], 1);
}
}
char maxValue = content[0];
int maxNum = 0;
for (Map.Entry<Character, Integer> entry : map.entrySet()) {
if (entry.getValue() > map.get(maxValue)){
maxValue = entry.getKey();
maxNum = entry.getValue();
}
}
System.out.println(maxValue + ":" + maxNum);