find all occurrences of a substring in a string code example

Example 1: python find all elements of substring in string

def find_all(a_str, sub):
    start = 0
    while True:
        start = a_str.find(sub, start)
        if start == -1: return
        yield start
        start += len(sub) # use start += 1 to find overlapping matches

list(find_all('spam spam spam spam', 'spam')) # [0, 5, 10, 15]

Example 2: find number of occurrences of a substring in a string java

public static int count(String str, String target) {
    return (str.length() - str.replace(target, "").length()) / target.length();
}