Here is a java code that count the occurrence of each character from text file.

import java.io.*;
import java.util.*;

class CountCharactersFromFile {
public static void main(String[] args) throws Exception{
FileInputStream fstream = new FileInputStream("C:\\data.txt");
DataInputStream in = new DataInputStream(fstream);
BufferedReader br = new BufferedReader(new InputStreamReader(in));
String strLine="";
String str="";
while ((strLine = br.readLine()) != null) {

str+=strLine;
}
String st=str.replaceAll(" ", "");
char[]third =st.toCharArray();
System.out.println("Character Total");
for(int counter =0;counter<third.length;counter++){
char ch= third[counter];
int count=0;
for ( int i=0; i<third.length; i++){
if (ch==third[i])
count++;
}
boolean flag=false;
for(int j=counter-1;j>=0;j--){
if(ch==third[j])
flag=true;
}
if(!flag){
System.out.println(ch+" "+count);
}
}
}
}