Write a java program
to count the frequency of each character in a given string.
import java.util.HashMap;
import java.util.Map;
import java.io.*;
public class
CharacterFrequencyCounter {
public static void main(String[] args) {
String inputString = "Hello,
World!";
// Create a HashMap to store character
frequencies
Map<Character, Integer>
charFrequencyMap = new HashMap<>();
// Iterate through the characters in
the string
for (char c :
inputString.toCharArray()) {
if
(charFrequencyMap.containsKey(c)) {
// Character already exists in
the map, increment the count
charFrequencyMap.put(c,
charFrequencyMap.get(c) + 1);
} else {
// Character does not exist in
the map, add it with a count of 1
charFrequencyMap.put(c, 1);
}
}
// Print the character frequencies
for (Map.Entry<Character,
Integer> entry : charFrequencyMap.entrySet()) {
System.out.println("Character:
" + entry.getKey() + ", Frequency: " + entry.getValue());
}
}
}
Output
C:\Program
Files\Java\jdk-11.0.17\bin>javac CharacterFrequencyCounter.java
C:\Program
Files\Java\jdk-11.0.17\bin>java CharacterFrequencyCounter
Character: , Frequency: 1
Character: !, Frequency: 1
Character: r, Frequency: 1
Character: d, Frequency: 1
Character: e, Frequency: 1
Character: W, Frequency: 1
Character: H, Frequency: 1
Character: l, Frequency: 3
Character: ,, Frequency: 1
Character: o, Frequency: 2
