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In this core java programming tutorial we will write a program to Find out count of all characters in string using HashMap (including special characters) in java.
Write a program to find out Find out count of all characters in string using hashMap, special characters also must be counted.
Example>
inputString is : This is it
Output is : T=1 h=1 i=3 s=2 =2 t=1
Full Program/SourceCode/ Example to Find out count of all characters in string using HashMap (including special characters) in java >
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;
/** Copyright (c), AnkitMittal www.JavaMadeSoEasy.com */
public class CharacterCountInStringUsingHashMapExample {
public static void main(String[] args) {
String inputString="This is it";
System.out.println("inputString is : "+inputString);
System.out.print("Output is : ");
characterCount(inputString);
}
/**
* Method calculates count of all characters in inputString.
*/
public static void characterCount(String inputString){
Map<Character, Integer> map=new LinkedHashMap<Character, Integer>(); //LinkedHashMap used so that we could maintain insertion order.
char[] inputAr=inputString.toCharArray();
for(int i=0;i<inputAr.length;i++){
char ch=inputAr[i];
if(map.containsKey(ch))
map.put(ch, map.get(ch) +1);
else
map.put(ch, 1);
}
/*
* Till this point of program, we have stored all unique characters in map as key & corresponding value representing count of character.
*/
Iterator<Character> charIterator=map.keySet().iterator();
while(charIterator.hasNext()){
char ch=charIterator.next();
System.out.print(ch+"="+map.get(ch)+" ");
}
}
}
/*OUTPUT
inputString is : This is it
Output is :T=1 h=1 i=3 s=2 =2 t=1
*/
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So in this core java programming tutorial we learned how to write a program to Find out count of all characters in string using HashMap (including special characters) in java.
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