new to java

[rotaryfreak]

i was just wondering if there was a method in java that would return the number of occurrences of a letter. for example, if the string was:

String hello = "Hello World";

id want a function that returns the occurrences of the letter "l" and would return an integer value of 3

any suggestions?

thanks

[sukatoa]

No, you may create your own specific character occurence counter......

sample method without loop:

private int occurs(String data,char find){
        return data.length()-data.replaceAll(find+"","").length();
    }

[JosAH]

No, you may create your own specific character occurence counter......

sample method without loop:

private int occurs(String data,char find){
        return data.length()-data.replaceAll(find+"","").length();
    }

That is intimidating for the OP; it assumes knowledge of regular expressions.
Better do it the naive way first:

private in occurs(String data, char find) {
 
   int count= 0;
   for (int i= 0; i < data.length(); i++)
      if (data.charAt(i) == find)
         count++;
   return count;
}

When the OP feels a bit more comfortable we can bring in the trickery-dickery again ;-)

kind regards,

Jos

[rotaryfreak]

Thanks Jos for your quick response, i appreciate it!

That is intimidating for the OP; it assumes knowledge of regular expressions.
Better do it the naive way first:

private in occurs(String data, char find) {
 
   int count= 0;
   for (int i= 0; i < data.length(); i++)
      if (data.charAt(i) == find)
         count++;
   return count;
}

When the OP feels a bit more comfortable we can bring in the trickery-dickery again ;-)

kind regards,

Jos

[chaarmann]

Jos solution is the fastest.
But if you don't care for the execution speed but only for the brevity of code, you can use:

int numberOfOccurrences = ("<" + "Hello World" + ">").split("l").length - 1;
 

You need to surround your original string by some characters that you are not searching for (I used "<" and ">"), if it may happen that a searchable character can be the first and/or last character of the string. If this cannot happen by the nature of your string, you can make this line even shorter:

int numberOfOccurrences = "Hello World".split("l").length - 1;