help, using casting type methods

Question about the task

Symbol frequency

Java Core, Level 8, Lesson 11

Under discussion

output is right,but not verfying

The program is started with one argument: the name of a file that contains text.
Calculate how often each symbol is encountered.
Sort the results by increasing ASCII code (read about it online).

Example:
','=44, 's'=115, 't'=116.

Display the sorted results:
[symbol1] frequency1
[symbol2] frequency2
Close the streams.

Example output:
, 19 - 7 f 361

Requirements:

You don't need to read anything from the console.
Create a stream to read from the file passed as the first argument of the main method.
You need to calculate the frequency of each symbol in the file and display the results.
The displayed results should be sorted by ascending ASCII code.
The stream used to read the file must be closed.

package com.codegym.task.task18.task1821; /* Symbol frequency */ import java.io.*; import java.util.*; public class Solution { public static void main(String[] args) throws IOException { TreeMap<Character, Integer> map = new TreeMap<>(); // BufferedReader bf = new BufferedReader(new InputStreamReader(System.in)); // String m = bf.readLine(); BufferedReader reader = new BufferedReader(new FileReader(args[0])); while (reader.ready()) { String s = reader.readLine(); char[] chars = s.toCharArray(); for (char ch : chars) { Integer count = map.get(ch); if (count == null) { count = 1; } else { count++; } map.put(ch, count); } } ArrayList<Integer> list=new ArrayList<>(); for(char i:map.keySet()){ list.add((int) i); } Collections.sort(list); for(int i:list){ System.out.println((char) i + " "+map.get((char) i)); //System.out.print(" "+map.get((char) i)); } // for (Map.Entry<Character, Integer> entry : map.entrySet()) { // System.out.println(entry.getKey() + " " + entry.getValue()); // } reader.close(); } }

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Skynet

Level 40 , USA

21 July 2020, 13:08

Try this: 1) Save the args[0] as a separate String variable. 2) Pass this variable to the FileInputStream in a try-with-resources block. 3) Inside the try block create a byte array and read all bytes using Files.readAllBytes(Path.get(yourStringVarHere)); 4) Next, inside the same try block, create a String variable and assign a new object with new String(bytesArr, StandardCharsets.US_ASCII); 5) Next, create a <Character, Integer> TreeMap; 6) Next, you will need a for loop like this:

for (int i = 0; i < s.length(); i++) {
      char var = s.charAt(i);
      if (map.containsKey(var)) {
          map.put(var, map.get(var) + 1);
     } else {
         map.put(var, 1);
     }
}

7) Next, iterate through the map and output in the required format. 8) Finally, add a catch block.

yz Backend Developer

21 July 2020, 12:23

br. ready() is not what you think, read about it, google how to use bufferedreader readLine() method

KIN SOCHEAT

Level 34 , Phnom Penh, Cambogia

21 July 2020, 08:08

try change Buffer to String fn = args[0]; FileInputStream fip = new FileInputStream(fn);

KIN SOCHEAT

Level 34 , Phnom Penh, Cambogia

21 July 2020, 03:00

your result is correct but try change line 30-38 Set set = map.entrySet(); Iterator it = set.iterator(); while (it.hasNext()){ Map.Entry print = (Map.Entry)it.next(); System.out.println((char)print.getKey() + " " +(int) print.getValue()); }