Counting occurrence of char character in Array list

Question

I wanted to create a method to search through a array list to see if the objects in the array list end with the given char character and then return the count of the character as a int.

public int OccurencesOfCharacter(Char givenCharacter){
....
}

Here's my array List

private ArrayList<Class> list;

For example if the Array List Contained [ Games, iphones] and my given occurrence character was 's' i want to return 2 because it appears twice at the end of the strings.

What ahve you tried so far? Why didn't those methods work? You've just given a method signature and a single variable. — Luke K, Nov 24 '17 at 10:48

score 0 · Accepted Answer · answered Nov 24 '17 at 10:54

Have a look on the sample below.

FULL CODE

import java.util.ArrayList;

public class Sample {

    private static ArrayList<String> list;

    public static void main(String[] args) {
        list = new ArrayList<>();
        list.add("Games");
        list.add("iphones");
        System.out.println(OccurencesOfCharacter('s'));
    }

    public static int OccurencesOfCharacter(char givenCharacter) {
        int count = 0;

        for(String s: list) {
            if(s.charAt(s.length()-1)==givenCharacter)
                count++;
        }

        return count;
    }

}

Other notes:

A char in Java is defined through the keyword char, not Char. You also could use the object Character, but never Char, unless it is some class defined by you.
I changed the type of your ArrayList from Class to String, since I'm not sure if Class is what you want to use.

Hope it helped!

score 0 · Answer 2 · edited Nov 24 '17 at 13:20

package demppractice;

import java.util.ArrayList;

public class AraylistEndWithS {
    public static void main(String args[])
    {
        ArrayList<String> list=new ArrayList<>();
        list.add("reshma");
        list.add("ramesh");
        list.add("kris");
        list.add("Games");
        list.add("phones");
        countOccouranceOfWord("s",list);
    }

   public static void countOccouranceOfWord(String ch,ArrayList<String> list)
    {
        int count=0;
        for(String ex:list)
        {
            if(ex.toLowerCase().endsWith(ch.toLowerCase()))count++;
        }
        System.out.println("count="+count);
    }
}

A simple explanation of what the code does would be good. – Al0x Nov 24 '17 at 11:46 — Al0x, Nov 24 '17 at 11:46

score 0 · Answer 3 · edited Nov 24 '17 at 13:04

Using char.I have use here ASCII for comparing capital and small letter.hope its helpful to you.

package demppractice;

import java.util.ArrayList;

public class AraylistEndWithS {
    public static void main(String args[])
    {
        ArrayList<String> list=new ArrayList<>();
        list.add("reshma");
        list.add("ramesh");
        list.add("kris");
        list.add("Games");
        list.add("phones");
        countOccouranceOfWord('s',list);
    }

    public static void countOccouranceOfWord(char ch,ArrayList<String> list)
    {
        int count=0;
        for(String ex:list)
        {
            char endwithchar=ex.charAt(ex.length()-1);
            int ascii = (int) endwithchar;
            int ascii2 = (int) ch;
            System.out.println("endwithchar="+endwithchar+"===ascii="+ascii);
            if(ascii==ascii2)count++;
        }
        System.out.println("count="+count);
    }
}

Java uses Unicode, not ASCII. As explained by the [Java documentation](https://docs.oracle.com/javase/8/docs/api/java/lang/String.html) `charAt` returns a UTF-16 code unit. UTF-16 is one of several encodings for the Unicode character set. — Tom Blodget, Nov 24 '17 at 23:27

Counting occurrence of char character in Array list

3 Answers3