Replace the character ‘e’ with ‘E’ in a word “Hello” in java

Question

I want to replace the character ‘e’ with ‘E’ in a word “Hello”. I'm reading the arguments from the prompt.

class LowToUpCase{
    public static void main(String[] args){
        if (args.length != 0) {
            String str = args[0];
            str = str.substring(1,2);
            System.out.println(str.toUpperCase());  
        }else{
            System.out.println("Give arguments");
        }
    }
}

Im getting the output as the Capitalised E only. But I'm not getting any idea how to get the output as hEllo . Please give me the hint to get the needed output.

[StringBuffer](https://docs.oracle.com/javase/7/docs/api/java/lang/StringBuffer.html) might be good for you. — RaminS, Jun 18 '16 at 18:50
He should use [StringBuilder](https://docs.oracle.com/javase/7/docs/api/java/lang/StringBuilder.html) instead of StringBuffer. — blacktide, Jun 18 '16 at 18:51
See http://stackoverflow.com/questions/6952363/replace-a-character-at-a-specific-index-in-a-string. — jarmod, Jun 18 '16 at 18:51
How should your program behave if the input is something other than Hello? Should it convert all e characters to E, or only the second character of the input? And what if the input is only a single letter? — Dawood ibn Kareem, Jun 18 '16 at 18:57

TimoStaudinger · Answer 1 · 2016-06-18T18:55:43.410

4

Why not replace the lower case e with its uppercase counterpart?

String str = args[0];
str = str.replace('e', 'E');
System.out.println(str);

Docs for String.replace().

edited Jun 18 '16 at 18:55

answered Jun 18 '16 at 18:52

TimoStaudinger

41,396
16
88
94

Thank you Sir !. I got the Output. I am a beginner in Java. Again Thanks for your help. – Anu Jun 18 '16 at 18:57
@Boann Sorry for ironing over your edit, `replace` is the better choice here of course. – TimoStaudinger Jun 18 '16 at 18:57

score 2 · Answer 2 · answered Jun 18 '16 at 19:01

2

You can use the replace() method from the String class.

class LowToUpCase{

   public static void main(String[] args){

   if (args.length != 0)
    {
      String str = args[0];
      str = str.replace('e', 'E');
      System.out.println(str);

    }else{
    System.out.println("Give arguments");
    }
  }
}

answered Jun 18 '16 at 19:01

Andres Elizondo

331
3
15

Isn't this just a duplicate of TimoSta's earlier answer? – Dawood ibn Kareem Jun 18 '16 at 19:13
Oh I didn't notice that, he replied while I was writing mine. – Andres Elizondo Jun 18 '16 at 19:24

score 2 · Answer 3 · answered Jun 18 '16 at 19:07

It appears that you also want to lowercase (at least) the first letter (so don't forget to call toLowerCase() on the input). I would prefer a StringBuilder (a mutable sequence of characters over modifying an immutable String) and something like,

StringBuilder sb = new StringBuilder(args[0].toLowerCase());
sb.replace(1, 2, sb.substring(1, 2).toUpperCase());
System.out.println(sb);

score 0 · Answer 4 · answered Jul 13 '18 at 12:19

0

String s="Hello";
String value=s.replace( 'e' ,'E');

answered Jul 13 '18 at 12:19

Vishal Sharma

1,051
2
8
15

Replace the character ‘e’ with ‘E’ in a word “Hello” in java

4 Answers4