Write code to return the number of occurrences of a character in a string
//package com.book2s; public class Main { public static void main(String[] argv) { String s = "book2s.com"; char ch = 'a'; System.out.println(numMatches(s, ch)); }/* w ww .ja v a2 s . c o m*/ /** * returns the number of occurrences of a character in a string */ public static int numMatches(String s, char ch) { if (s == null) return 0; int result = 0; for (int i = 0; i < s.length(); i++) if (s.charAt(i) == ch) result++; return result; } /** * returns the number of occurrences of a substring in a string */ public static int numMatches(String s, String search) { if (s == null || search == null || "".equals(s) || "".equals(search)) return 0; int result = 0; int curIndex = 0; while (true) { curIndex = s.indexOf(search, curIndex); if (curIndex == -1) break; curIndex++; result++; } return result; } }