Finding the Most Common Character in a String

static int countChars( String str, char searchChar ) {
// Count the number of times searchChar occurs in
// str and return the result.
int i; // A position in the string, str.
char ch; // A character in the string.
int count; // Number of times searchChar has been found in str.
count = 0;
for ( i = 0; i < str.length(); i++ ) {
ch = str.charAt(i); // Get the i-th character in str.
if ( ch == searchChar )
count++;
}
return count;
}